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krag123
25-10-2007, 01:00
I am trying to make an Imperial Guard army as real as i possibly can make it and a few questions have come to the front. What would the real world equivalent be to some 40k weapons?

Right now I'm primarily focusing on an artillery battalion so here are my suggestions or match ups and i would like to see if people agree or not.

Imperial Heavy Mortar = 105mm Howitzer : http://www.forgeworld.co.uk/heavymort.htm
Heavy Artillery carriage with Earthshaker Cannon = 155mm Howitzer: http://www.forgeworld.co.uk/acatalog/DEATH_KORPS_OF_KRIEG.html

Heavy Weapons:

Heavy Bolter: 30mm Infantry machine gun (a bit of a stretch)
Autocannon: 50 cal Heavy machine gun

Let me know what you think, i could be off or i could be spot on. But I think this could be an intersting discussion if it has not been asked before.

Omniassiah
25-10-2007, 01:08
If anything the Heavy Stubber would be a 7.62 machine gun and the Heavy bolter would be a .50cal and the autocannon would be a 25 or 30mm Machine gun.

Reflex
25-10-2007, 01:12
some of the coolest conversions i have seen are people swap the lasguns for Lee Enfield rifles or Mauser K98's. it makes them look really nice, especially seeing them on the DKoK models. so if you get around to that do it.

Omniassiah has it pretty spot on with the calibers though.

Orcboy_Phil
25-10-2007, 01:14
Well your standard assualt rifle is Str 3 (Autogun) and a machine gun is Str 4 (Heavy Stubber). the problem is that beyond that we don't have any of the more exotic weaponry to compare things too. When was the last time you saw a mass reactive round for example. You could compare the Autocannon to one of the smaller tanks main guns (don't ask me which I'm not a treadhead). For the heavy bolter I'm not really sure, I can't remember where but I'm sure I read or heard somewhere that they used depleated uranium rounds. Which really dosen't tie in with an Anti-tank role. There fairly usless again't most tanks.

CrewDog
25-10-2007, 01:17
The heavy bolter is so a Mk19 auto grenade launcher.

Omniassiah
25-10-2007, 01:22
Nah don't try and compare it weapon stats to actual stats of real weapons just what the equivalent would be. Sure a M2 Browning .50 cal Doesn't have the explosive shells a heavy bolter has but the rate of fire and effective damage is similar, same with some of the older 25mm or 30mm heavy machine guns. Or you could drop it a bit and go Stubber 5.56mm light machine gun like a M249 SAW, M240B 7.62mm Machine gun for a heavy bolter, and the autocannon being the M2 .50cal

Khobai
25-10-2007, 02:55
Sure a M2 Browning .50 cal Doesn't have the explosive shells a heavy bolter has but the rate of fire and effective damage is similar

.50cals are way too big to be the equivalent of a heavy bolter. the heavy bolter is handheld and man-portable. .50 cal is more like an assault cannon.

legio mortis
25-10-2007, 03:05
Heavy Stubbers can vary from light 5.56mm SAW like weapons to .50 cal. machine guns. It all depends on the model. Heavy Bolters would be somewhere around the 1.00 to 1.5 caliber range, seeing as the standard bolter round is .75 cal. Autocannons are even bigger, somewhere around the 50 to 60 mm range.

Outlaw289
25-10-2007, 03:06
.50cals are way too big to be the equivalent of a heavy bolter. the heavy bolter is handheld and man-portable. .50 cal is more like an assault cannon.

Are. you. kidding. me?

Heavy bolters are the equivalent of like, a a Bushmaster 25mm autocannon. Hell, regular Bolters themselves are damn close to being 20mm (19.083 is equivalent to .75 caliber I believe), and heavy bolters are significantly larger than regular bolters.

An assault cannon in 40k terms is more similar to a GAU-8 like on the A-10. A .50 cal would never be represented with S7 and rending.


In 40k terms...
S3 represents most common assault rifles/smgs from 5.56 to 7.62 to 9mm. The unfortunate side effect of having a wide array of variables compressed into a D6 format

S4 represents everything from 12.7 to 14.5 to 20mm, which would encompass things like AT rifles, heavy machine guns, and (modern day) autocannons.

S5 is things like heavier autocannons and anti-aircraft weaponry, and from there on up it just gets bigger/nastier

Halcyon504
25-10-2007, 03:30
(Auto)cannons are pretty big weapons. The real world standard definition of a "Cannon" is any gun that is 20mm or larger. Thus, the GAU-8 Avenger can be considered a cannon(30mm), and many classic cannons, such as the 40mm Bofors and the 20mm Oerlikon are still in use today. Then there's tank sized cannons, with 120mm being pretty standard amongst NATO armies.

I would think that the Autocannon/Reaper Autocannon/Assault Cannon family are within the 20mm range. Even for Space Marines I cannot imagine any bigger round being fired by these weapons and still be able to withstand the recoil. Vehicle autocannons are probably larger, within the 50-90mm range I would believe. It would seem that any larger calibers would then cross into the "Battle Cannon" range.

max the dog
25-10-2007, 03:44
Actually I look at it more like this;
Heavy Artillery carriage with Earthshaker Cannon = http://www.fas.org/man/dod-101/sys/land/m110a2.htm
Heavy Bolter = http://www.fas.org/man/dod-101/sys/land/m240g.htm
Heavy Stubber = http://www.fas.org/man/dod-101/sys/land/m2-50cal.htm
Autocannon = http://www.fas.org/man/dod-101/sys/ship/weaps/mk-38.htm

Dooks Dizzo
25-10-2007, 04:27
The heavy bolter really is more like a Mk19, just without the 5m kill radius.

Durath
25-10-2007, 04:30
Not quite Real World yet, but soon...

http://www.popsci.com/popsci/technology/generaltechnology/64669aa138b84010vgnvcm1000004eecbccdrcrd.html

We = Tau?

Also.... http://dsc.discovery.com/fansites/future-weapons/weapons/zone2/milkor-m32.html = more of a bolter.

Bookwrak
25-10-2007, 08:35
.50cals are way too big to be the equivalent of a heavy bolter. the heavy bolter is handheld and man-portable. .50 cal is more like an assault cannon.

You meant to say, "way to small." There are pistols that chamber .50 rounds, and I have yet to meet a non-man portable pistol.

Sekhmet
25-10-2007, 09:35
If the autocannon is a 20mm machine gun.. why is it fielded by space marine predator destructors as the standard, sole turret-mounted weapon?

It's strength is MUCH greater than that of the heavy bolter (S7 v S5) with a lesser fire rate... so... find something else...

Galatan
25-10-2007, 10:25
You can't really compare anything bigger than the autocannon with real world weapons. And the bolter and heavy bolter would be extremely hard to compare. A normal guardsman needs extensive augmentic surgery or great strength to even be able to deal with the recoil of a bolter (and the ones guardsmen get are a smaller version). A bolter you can compare with.....a rapid firing light rocket launcher since it can easily blow you up and pierce the armour of light 40k tanks (which are quite heavy tanks in the real world). A heavy bolter is something a tank will only be ever able to carry or a heavy weapons crew that has a special carriage for it.
The assault cannon is just a smaller version of the gatling gun which are deployed on things like ships.

Anything bigger than this and we are beyond the missile launcher and we are outside our capacity, leman russ shells and lascannons are able to bring down titans and stuff....I don't see a real world weapon doing that. Maybe planes, bunker busters are pretty nifty.

Cheers,
Galatan

the_raptor
25-10-2007, 11:41
A bolter you can compare with.....a rapid firing light rocket launcher since it can easily blow you up and pierce the armour of light 40k tanks (which are quite heavy tanks in the real world).

They are? Imperial ones are agricultural tractors with armour plate slapped on.


Anything bigger than this and we are beyond the missile launcher and we are outside our capacity, leman russ shells and lascannons are able to bring down titans and stuff....I don't see a real world weapon doing that. Maybe planes, bunker busters are pretty nifty.

Have you seen what a 155mm round can do? Titans aren't hard, they only seem hard because most races in the 40k universe have craptastic technology. Which is why the Tau can take out Titans with the equivalent of a C-130 gunship.

40k armour isn't that much better then modern composite armour. And that is easily defeated by most modern AT weapons.

Bunnahabhain
25-10-2007, 11:56
Basalisks are specified in imperial armour at 132mm diameter, with a 38kg shell, which gives a range of 15km, at a muzzle velocity of 814 m/s. The other figures are roughly consistient with the stated calibre.
Leman Russ main gun should be somewhere about 120mm. The model implies a calibre of about 5-600mm, but we'll ignore that, as it's silly.
Demolisher would be equivilent to a short range demolition mortar, which cropped up between about 150 and 200mm

Cruisers were fairly solidly built ships, with quite reasonable armour, so should be a rough comparison for a smaller titan . Main guns roughly 150-200mm, and their armour was no match for their own guns.

Rapid firing cannons/autocannons commony used 37mm ammo, and the 40mm bofors was also common. This is larger that the the heavy bolter, which is often quoted as 1inch, ie 25mm.

The whole scale vs calibre vs real life thing is hoplessly tangled up. Assualt cannons are the worst offender, but lots of others are almost as bad.

krag123
25-10-2007, 12:40
I can see where i made a miss step in my suggestion of heavy weapons. I was in a hurry last night to finish the post and had preaty much shut off the logic portion of my brain. I agree that i may have under sized the Heavy bolter and Auto cannons.

I would have to change my Auto Cannon equivalint to be something similar to the Bradly Fighting Vehicals main gun. And i could see the the Heavy Bolter being something similar to the Humvee mounted Auto Grenade launcher (which is the coolest thing ever). But if that is the equivalent of the weapon it does not seem like a weapon you would want to put into an infantry squad.

Heavy weapons aside i think this is turning out to an interesting discussion. I also agree that that somethings just don't have a real world counterpart.

Wolflord Havoc
25-10-2007, 13:22
With the exception of the 'super human power armour agmented Space Marines' most heavy weapons are 'crew served' that is to say they require several (2) crew to carry and operate the weapon.

I don't think that you can compare the weapons of today with the weapons of the 40K universe. However I will give it a try.

Las Pistol/Auto pistol - 9mm and 11.43mm (sorry .45 cal) etc pistol weapons capable of being fired in one hand

Lasgun/Auto gun - Semi or fully automatic weapons in the 5.45/5.56 and .308/.303 and 7.62mm range. I am going to say that bolt action rifles would not be the equivilent their ROF is too slow - however Sniper rifles might be.

Shotguns - I am going to lump SMGs in with shotguns here as they fullfill the roll of '40K shotguns' i.e. a weapon capable of controlled short range rapid fire.

Bolt weapons - we have several sources indicating that the weapon is in the .75 cal. I have never seen anything to indicate that the heavy Bolter is using larger ammo so I guess that we are looking at the US 25mm explosve bullet weapon component of the ill fated XM29 OICW or it French Equivilent (can never remember what its called).

Grenade Launcher - um easy one - 40mm grenade launcher such as the Hawk MM1

Flame Thrower - Flame Thower (M2A1 a7)

Melta Gun - not so easy - this looks like a weapon that focus's microwaves (duck and cover) at a particular point - superheating it in a very short period of time (must be a fraction of a second otherwise it would be useless). We have no equivilent.

Plasma Gun - not even going to raise my head above the parapit on this one.

Missile Launcher (tread fether) - I am going to go for a 1960s style man portable recoiless rocket launcher such as the Carl Gustav 84mm or the RPG 7 / BF40 Rocket launchers - or more simply Bazookas and Panzerfausts.

Mortar - An 80 - 82 mm Mortar such as the L16A2 81mm Mortar

Autocannon - now this for me is something like a 20mm Oerlikon cannon (I am looking at the Cadian heavy weapon) or 2 cm FlaK 30 except then we have the issue of the ammo being comparable to bolter ammo so we have to upsize to 25mm or even upto 37mm or 40mm for the weapons on the Predator and Leman Russ Exterminator. I would suggest that the larger weapons have a lower rate of fire.

Lascannon - we have not got an equivilant to this (certainly not battlefield deployable) and so the only close match we have is AT-missiles such as the Milan or Javalin.

Montserrat
25-10-2007, 13:37
er...THATS an autocannon.. 57mm autocannon...medium caliber

http://es.youtube.com/watch?v=_okvBRnVCfw

PD: AP system sucks

Argastes
25-10-2007, 13:57
Are. you. kidding. me?

Heavy bolters are the equivalent of like, a a Bushmaster 25mm autocannon. Hell, regular Bolters themselves are damn close to being 20mm (19.083 is equivalent to .75 caliber I believe), and heavy bolters are significantly larger than regular bolters.

An assault cannon in 40k terms is more similar to a GAU-8 like on the A-10. A .50 cal would never be represented with S7 and rending.

:confused: Are YOU kidding me? An assault cannon a GAU-8? Since a GAU-8 is about 20 feet long (6.4 meters) and is fed from a magazine the size of a 500-gallon LP tank, and develops recoil forces so powerful that firing even a SINGLE round would knock a terminator-armored space marine flat on his ass (yes, that's right) even if he could lift and carry a weapon that's three times as long as he is tall.... I don't think so. An assault cannon is comparable to an M134 7.62mm minigun or a GECAL-50 12.7mm gatling machine-gun (the six-barreled one, not the three-barreled version the US military uses).

People have mentioned that, in real-world weapons systems, there is an overlap between what would be similar to a heavy bolter and what would be similar to an autocannon, because of the caliber similarity that arises if we don't assume an impractically large caliber for the autocannon (impractical because it's supposed to be portable on a light carriage with a two-man crew). But this argument overlooks the fact that there is much more to a weapon's power than it's caliber. I think the solution is fairly simple: A heavy bolter is similar to a low-velocity automatic cannon (or automatic grenade launcher) firing explosive shells, whereas an autocannon is more like a long-barreled, high-velocity automatic cannon firing armor-piercing shells. So a heavy bolter's real-world equivalent would be an M307 or AGS-17 with HEAP ammunition, whereas an autocannon would be any number of automatic cannon in the 20-25mm range which develop muzzle velocities above 800 m/s, loaded with kinetic AP or APDS ammo.

Here's how it would break down:
Heavy stubber: .50-caliber or 12.7mm HMG. Not a 7.62mm HMB, because 7.62mm-equivalent weapons (infantry rifles) seem to have STR 3, and because it's typically seen mounted as a tank commander's pintle MG, and because the weapon itself is obviously inspired by the US M2, and because the 2nd Edition wargear book explicitly described it as comparable to a modern-day heavy machine gun.
Heavy bolter: Low-velocity automatic cannon, or AGL, in the 25-30mm range firing HEAP shells.
Autocannon: High-velocity automatic cannon in the 20-25mm range, firing AP shells
Assault cannon: Gatling machine gun in the 7.62mm to 12.7mm range (a "minigun")


If the autocannon is a 20mm machine gun.. why is it fielded by space marine predator destructors as the standard, sole turret-mounted weapon?

Why shouldn't it be? Automatic cannon in the 20-30mm range are perfectly common as turret armaments for modern light/medium fighting vehicles. Remember, a Predator isn't a "main battle tank"; it's a light tank, based on an APC hull with the addition of a one-man turret and some additional armor.


er...THATS an autocannon.. 57mm autocannon...medium caliber

WAY too big to be a 40K autocannon... that's a naval mounting for AA and point-defense use, to give you an idea of why. Such a weapon could never be lugged around by two Guardsmen or a single CSM. On the ground, a 57mm cannon requires a dedicated vehicle or a large (multi-ton) towed carriage.


PD: AP system sucks

Seconded.


When was the last time you saw a mass reactive round for example.

Shells designed to penetrate armor and then explode inside the target have existed since the early 20th century. They haven't been called "mass reactive" (a silly term anyway), but the technology is nothing exotic.

Sekhmet
25-10-2007, 16:05
Why shouldn't it be? Automatic cannon in the 20-30mm range are perfectly common as turret armaments for modern light/medium fighting vehicles. Remember, a Predator isn't a "main battle tank"; it's a light tank, based on an APC hull with the addition of a one-man turret and some additional armor.


A light tank would be a chimera. 13AV is NOT "light" in 40k terms.

Argastes
25-10-2007, 16:50
A light tank would be a chimera. 13AV is NOT "light" in 40k terms.

A Chimera is an infantry fighting vehicle, which is--by definition--a completely different class of vehicle from the light tank. If it's purpose-built to transport an infantry squad, it's not a light tank, even if lots of IG players use them as, or think of them as, light tanks on the tabletop. Comparatively thick frontal armor does not exclude a vehicle from the category of "light tank". The M8 Buford AGS--a light tank considered as a replacement for the M551 Sheridan in US airborne divisions--could be fitted with a quite substantial armor package despite being a member of the light tank class.

The Predator may have good frontal armor, but it's still:

A). Based on an APC hull; and

B). Lightly armed (when you consider that every one of it's possible weapons systems can apparently be moved around by a two-man crew).

Whether a vehicle is a light tank is not determined solely by it's armor.

krag123
25-10-2007, 16:56
I wouldnt call it a light tank, but i also wouldnt go as far as calling it a heavy either. Here are the classes as i see them:

Light Tank: Transports/Razorbacks
Medium Tank: Preditors
Heavy Tank: Land Raider
Supper Heavy: Baneblade

The Russ would be hard to place. It has a 14 AV for the front, but the sides are only 12, which does make it preaty hard to beat but at in the rear armor of 10 and your preaty vunerable and are not really in the same class as a Land Raider.

While and the Chimera is also a shaky one as well. While it has a 12 front, it carries more firepower then the Razorback, with 2 vehical weapons, 6 fire ports, and the ability for one guy to pop out the top and shoot his melta/plasma or any other nice weapon.

Sekhmet
25-10-2007, 16:59
A Chimera is an infantry fighting vehicle, which is--by definition--a completely different class of vehicle from the light tank. If it's purpose-built to transport an infantry squad, it's not a light tank, even if lots of IG players use them as, or think of them as, light tanks on the tabletop. Comparatively thick frontal armor does not exclude a vehicle from the category of "light tank". The M8 Buford AGS--a light tank considered as a replacement for the M551 Sheridan in US airborne divisions--could be fitted with a quite substantial armor package despite being a member of the light tank class.

The Predator may have good frontal armor, but it's still:

A). Based on an APC hull; and

B). Lightly armed (when you consider that every one of it's possible weapons systems can apparently be moved around by a two-man crew).

Whether a vehicle is a light tank is not determined solely by it's armor.

So what's a land raider? It IS an APC hull and it also falls under your categorization of "lightly armed" in that every weapon it fields can be moved around by a two man crew.

Wolflord Havoc
25-10-2007, 17:15
The Russ would be hard to place. It has a 14 AV for the front, but the sides are only 12, which does make it preaty hard to beat but at in the rear armor of 10 and your preaty vunerable and are not really in the same class as a Land Raider.

I would call it a "Main Battle Tank" - a happy medium between the Predator and the Land raider in armor and combat capabilities - while being less complex than either vehicle in background terms.

In fact I always saw the Leman Russ as an M4 Sherman (which makes the Vanquisher a Sherman Firefly :D ) - not the best tank, but the most numerous and easy to build and maintain (and yes I know the Russkies built more T34s before someone jumps in and slaps me - but it does look more like an M4 Sherman).

Argastes
25-10-2007, 17:21
So what's a land raider? It IS an APC hull and it also falls under your categorization of "lightly armed" in that every weapon it fields can be moved around by a two man crew.

"Built with a troop compartment" and "Built on an APC hull" are two radically different things. A Merkava MBT has a troop compartment but you couldn't say that it "IS an APC hull". When I say the Predator is "built on an APC hull", I mean it is made by taking the 41st-millennium version of an M113 and putting on a small turret and some extra armor. The Land Raider is an entirely different case, and just because it includes a troop compartment doesn't mean that "is an APC hull". It's a large tank hull which happens to have a troop compartment in it. As for it's weapons, it's true that they're all also used by two-man crews, but it has a significantly larger complement of them.

EDIT: And by modern standards, the Land Raider is kind of a worthless vehicle anyhow. It tries to be a well-protected APC and a main battle tank at the same time, meaning it sort of sucks at both roles (yeah, yeah, I know it doesn't suck on the tabletop; I'm giving a realistic assessment, not a rules-based assessment). By modern standards, the Predator is a light tank (or at best, a poorly-armed medium tank) and the Land Raider is a pointless waste of resources and a perfect illustration of the saying "jack of all trades, master of none".

carl
25-10-2007, 17:31
Take a look at the autocannon model, specificlly the brass cases and the way they compare to the barrel and people, then do the same for the shell cases that 57mm ejects, (see the grand finale bit right at the end, their nea the bottom of the turret).

Also, real world considerations on tank armerment really don't apply here.

As somone else noted the Preadetor mounts the Autocannon as it's main gun and we KNOW it's supiriour to a havy Bolter and we KNOW a heavy blter is bigger than a Bolter.

that puts the Autocannon at WELL OVER 30mm since 30mm is the supposed calibre of the Heavy Bolter.

And yes the Assuallt cannon is a GAU-8 equivelent in some respects.


What people ALLWAYS FORGET about 40K is that in comparision to the calibre of the gun, the barrels are VERY short. A 57mm weapon CAN be man portable, it just needs a very shprt barrel firing low preashure ammo. That limits it's max range and penetrating power, but it's damm dangerous all the same.

carl
25-10-2007, 17:39
this (http://www.youtube.com/watch?v=F3v8AN_fJlQ) is the real world equivelent of a bolter, now scale that up for a heavy bolter, and even furthar for an autocannon...

Orbital
25-10-2007, 17:52
Shuriken Catapults.

http://www.gadgetpages.com/shopimages/products/normal/DiscGun.jpg

krag123
25-10-2007, 19:21
this (http://www.youtube.com/watch?v=F3v8AN_fJlQ) is the real world equivelent of a bolter, now scale that up for a heavy bolter, and even furthar for an autocannon...

Ah thanks, i have been looking for that for my statement about the bolter. It is true that mini granade and shotgun combo is the perfect representation of what a boltgun truly would be in the real world.

Outlaw289
25-10-2007, 21:26
:confused: Are YOU kidding me? An assault cannon a GAU-8? Since a GAU-8 is about 20 feet long (6.4 meters) and is fed from a magazine the size of a 500-gallon LP tank, and develops recoil forces so powerful that firing even a SINGLE round would knock a terminator-armored space marine flat on his ass (yes, that's right) even if he could lift and carry a weapon that's three times as long as he is tall.... I don't think so. An assault cannon is comparable to an M134 7.62mm minigun or a GECAL-50 12.7mm gatling machine-gun (the six-barreled one, not the three-barreled version the US military uses).

I was considering the ones mounted on Baals and Dreadnoughts. The fact that Terminators can carry them is the result of bad scifi scaling. By your logic, Guardsmen can't have lasguns, because a contemporary power source for lasguns is huge, but in 40k enough power for 40 lethal lasgun shots fits into a box about the size of a fist.

I just don't think that a RENDING S7 AP4 rotary cannon is the fictional equivalent of a .50 cal anything. The Heavy stubber is what an M2 machine gun would be, the GECAL one you mentioned would be like S4 AP6 Heavy 4

It's just that the 40k assault cannon can penetrate MBTs, has a ridiculous rate of fire, and is two levels of magnitude stronger than a heavy bolter, which we already established is a 25mm automatic mini-rocket launcher. It's comparable to the GAU-8 in all things but size. You picked petty details to disagree with me about.

Argastes
25-10-2007, 21:28
Take a look at the autocannon model, specificlly the brass cases and the way they compare to the barrel and people, then do the same for the shell cases that 57mm ejects, (see the grand finale bit right at the end, their nea the bottom of the turret).

Taking the scale of 40K models as a reliable indicator of their "real" size is guaranteed to provide inaccurate results. GW always exaggerates the size of things like that on their models. And even allowing for that exaggeration, the cases visible in the drum feed of an IG autocannon are STILL too small be 57mm; a complete round of 57mm ammunition is nearly 2 feet in length.


As somone else noted the Preadetor mounts the Autocannon as it's main gun and we KNOW it's supiriour to a havy Bolter and we KNOW a heavy blter is bigger than a Bolter.

that puts the Autocannon at WELL OVER 30mm since 30mm is the supposed calibre of the Heavy Bolter.

No, you obviously don't understand what determines how powerful a weapon is. A weapon's power can not be estimated just by looking at it's caliber. The fact that an autocannon has a higher strength than a heavy bolter is no indication that it is of even slightly larger caliber, much less than it's "WELL OVER" a heavy bolter's caliber. It's perfectly possible that it is of SMALLER caliber than a heavy bolter despite it's greater hitting power. Velocity and ammunition type are just as important as caliber. What's more, projectile length determines the power of a weapon just as much as projectile diameter (caliber). Look at real-world examples: A 25mm automatic cannon such as the M242 is massively more powerful than a 30mm grenade launcher such as the AGS-17. Because it fires at a much higher velocity. So the fact that a heavy bolter is of 30mm caliber doesn't at all prove that an autocannon must be "WELL OVER" 30mm to account for it's greater strength; it could be well under 30mm and still have a greater strength.


And yes the Assuallt cannon is a GAU-8 equivelent in some respects.

What respects? Other than the fact that they're both multi-barreled Gatling-type designs? It's not even close to equivalent in power or size.


What people ALLWAYS FORGET about 40K is that in comparision to the calibre of the gun, the barrels are VERY short. A 57mm weapon CAN be man portable, it just needs a very shprt barrel firing low preashure ammo. That limits it's max range and penetrating power, but it's damm dangerous all the same.

No, even if you took a 57mm cannon and cut the ENTIRE barrel off--I mean cut it off right after the chamber--it could not be hauled around by a two-man crew the way 40K autocannons are. It's much too big. We're talking about a gun where EACH ROUND of ammunition is nearly two feet long. Even without any barrel at all, it would be much too massive and heavy.

Anyhow, 40K weapon barrels might be comparatively short on boltguns and such, but on autocannons, they are clearly quite long. They may be a little thick in comparison to their length, but that's because if they were any thinner, the models would break too easily. Anyone who's ever assembled real historical models will know what I'm talking about. An IG autocannon is definitely nothing like a 57mm Bofors gun with the barrel cut down.

Since you don't seem to appreciate just how huge a 57mm automatic cannon is, here are a few pics to help clarify for you:

http://fas.org/man/dod-101/sys/land/row/s-60-aaa.jpg (note the size of the gunner, who is visible in silhouette seated on the right-hand side of the gun mount)

http://fas.org/man/dod-101/sys/land/row/s-60_57mm-aa_002.jpg

http://fas.org/man/dod-101/sys/land/row/s-60-line.gif (this one clearly demonstrates the size of carriage needed to mount a 57mm gun; notice how much huger it is than the little man-portable, two-wheeled lightweight carriage used by IG autocannon, which are much more similar to those used for 20mm cannons in real life).

Omniassiah
25-10-2007, 21:28
I can't not stress it enough but do not compare calibers of real-life weapons to 40k ones. GW uses 28mm Hero scale for their models. That means things like gun barrels, heads, hands, and other details are exaggerated to allow for easier painting. For the same reason don't compare Strength to caliber because your not taking in to effect things like rate of Fire. Putting 3-5x the rounds on a target will inflate the strength of a weapon a bit in 40k instead of having heavy bolters being Heavy 15 or such.

End result best comparison that the guys came up with for equipment is such

Las pistol - 9mm side arm
Las Gun - Basic Infantry Rifle
Heavy Stubber - 5.56mm LMG like the M249 Saw
Heavy Bolter - 7.62mm MMG like the M60/M240B
Autocannon - .50cal HMG like the Browning M2 "Ma Deuce"
Missle Launcher - AT-4 or equvilant
Multi-lasers and Lascannon - we'll these start to get really screwy. and nothing truely fits here in RL comparison
Assault Cannon- 5.56mm Electric gatling gun.
Think thats most of the Infantry weapons that aren't obvious

Vehicles
Sentinals - Jeep/Humvee (yes I know they aren't walkers)
Chimera hulls - M113/Bradleys and varients
Leman Russ - Any MBT.

And the GAU-8 would be best represented by the Vulcan mega bolter with the IA update rules where it had rending. the reason I put a 5.56mm Gatling as a Assault cannon is because the Rending rule is frankly one of the worst rules in the 40k book by far IMO. It may work for some fancy Alien weapon but not for a lot of the stuff its used for.

Outlaw289
25-10-2007, 21:39
Are we talking about what the equivalent ROLES of 40k weapons would be in the real world, or the equivalent TYPE? If we're talking roles then I agree with Argastes' line of reasoning

Omniassiah
25-10-2007, 21:45
By the OP its roles not type as he wants to build a modern day style 40k IG army if I understood him correctly. even with type it would still be pretty close between my list or Argastes'.

Argastes
25-10-2007, 21:53
I was considering the ones mounted on Baals and Dreadnoughts. The fact that Terminators can carry them is the result of bad scifi scaling. By your logic, Guardsmen can't have lasguns, because a contemporary power source for lasguns is huge, but in 40k enough power for 40 lethal lasgun shots fits into a box about the size of a fist.

No, you're equivocating my argument with a similar, but less valid, argument. Electrical power supplies are much more subject to miniaturization than are projectile-firing weapons. It's entirely reasonable to claim that 40K electrical power sources are more compact than modern ones, but 40K firearms don't seem to have made such a leap, so it's less reasonable to claim that an assault cannon could pack as much power as a GAU-8 into a package one-fifth the size. Autoguns are equivalent to modern assault rifles; autocannons are equivalent to modern automatic cannon; why do you think that assault cannons, unlike all other 40K firearms which obviously analogous to modern firearms, have been radically miniaturized so that they can pack the punch of a GAU-8 despite not being so big that they fill a semitrailer?


I just don't think that a RENDING S7 AP4 rotary cannon is the fictional equivalent of a .50 cal anything. The Heavy stubber is what an M2 machine gun would be, the GECAL one you mentioned would be like S4 AP6 Heavy 4

No, you are radically underestimating the destructive power of a weapon that fires at several thousand rounds per minute. If a heavy stubber is a .50 HMG and an assault cannon is a .50 Gatling gun, the assault cannon would be more than TEN TIMES as powerful as a heavy stubber--since an M2 fires at 500 rounds per minute and the six-barreled GECAL could fire at 8,000 rounds per minute. You think that this massive increase in destructive power is accurately reflected by giving it one or two extra shots over a heavy stubber and leaving the rest of it's profile unchanged? Absurd. It's obvious that the assault cannon is S6 (not S7, by the way) AP4 and Rending, whereas a heavy stubber of similar caliber is only S4 AP6, because each of the assault cannon's four "shots" represents dozens of projectiles impacting in a fraction of a second. Such impact has an erosive effect on armor, allowing the weapon to penetrate armor that couldn't be penetrated by fewer projectiles of the same caliber (pretty good explanation of Rending, as far as I can tell).


It's just that the 40k assault cannon can penetrate MBTs, has a ridiculous rate of fire, and is two levels of magnitude stronger than a heavy bolter, which we already established is a 25mm automatic mini-rocket launcher. It's comparable to the GAU-8 in all things but size. You picked petty details to disagree with me about.

The assault cannon can penetrate MBTs sometimes and rarely destroys them even when it does penetrate, whereas the GAU-8 is such an unstoppable tank-killer that a single quick burst is pretty much guaranteed, inescapable destruction for ANY tank in the world. If an equivalent to the GAU-8 existed in 40K, it would probably be S10 AP2 (or AP1). And the assault cannon is so much stronger than a heavy bolter because each of it's in-game "shots" represents dozens of rounds, not a couple as is the case with the HB. I'd agree that each individual round from an HB is more powerful than each individual round from an assault cannon, but the assault cannon fires at 10-20 times the cyclic rate, and it wouldn't be very practical in game terms to have a weapon with a statline that read "S4, AP5, Heavy 50".

I didn't pick petty details to disagree with you about; I pointed out that the GAU-8 is much bigger and more powerful than the assault cannon. That's about as relevant and important as you can get.

carl
25-10-2007, 22:52
@ Argete's:

First and foremost I DO know about the old bigger than life weapons, theirs no way a heavy bolter is in scale, the calibre is probably about 50mm itself if you treat it in scale.

That’s why I mentioned the predator, First and foremost, remember the Heavy Bolter fire rocket assisted rounds, their is absolutely no reason therefore why a heavy bolter would be ANY less powerful than a contemporary 30mm long barrelled cannon like the various Orlerkien Models, (pardon the spelling please).

Add to that that we know from fluff sources that the Autocannon is about the same fire rate as a heavy bolter, (fully automatic and faster than a man can pull the trigger, but not up to the standard of multi-barrel cannon or small calibre machine guns), we can dismiss the "high S is cause of multiple shots" theory for the mot part.

The simple fact is where dealing with a weapon vastly more powerful than a standard modern 30mm cannon. Unless your suggesting a stupidly long barrel and stupidly high barrel pressures then we can confidently say it is vastly larger than 30m, not to mention that the Artwork, (for the most part), isn't done in heroic scale, and that DOES show it as large calibre too.

And no 57mm ammo isn't 2ft long, its however long you bloody well make it, but you completely skipped the short barrel low pressure statements I gave which would explain that to you quite clearly.

With low barrel pressure and a short length barrel you need far less gas from the cartridge, that means a MUCH smaller cartridge section and a much smaller breach and barrel with much thinner materials being involved since it doesn’t need to be as strong because of the lower pressures.

The weapon won't have the range or punch of a proper 57mm, but the large size of the ammo will still make it pretty evil to whatever it hits.


The assault cannon and the GAU-8 share 1 simple point, their multi-barrel cannon firing huge amounts of large calibre rounds at the opposition.


And on top of that you really should try to remembers that GW just doesn’t give a damm about what’s possible, fluff wise the Assault cannon has all the effects of a GAU-8 on it's targets, right down to chewing up MBT's. Even I can't figure out a realistic way to make that work, but that’s what it can do and thus the real world equivalent IS the GAU-8, no matter how littlie sense it makes.

Your list was nice if you just want the RL weapons that fill the same role, but totally wrong if you want RL weapons of equivalent power, which is what I believe the discussion is centred on.

krag123
25-10-2007, 23:03
By the OP its roles not type as he wants to build a modern day style 40k IG army if I understood him correctly. even with type it would still be pretty close between my list or Argastes'.

What I am looking for is something that would fill the roll of the 105mm Howitzer, and the 155mm Howitzer's. I am basing my army after a WW2 formation i found, Which consisted of 9 infantry brigades, and 1 artillery brigade. Now i know that would be an insane amount of models I plan to only represent a small portion of this force.

In the end i hope to field an Entire Battalion of Infantry (about 500men) and an Artillery Battalion (9 guns)

I was figuring that the Heavy Mortar best filled the roll of the 105mm, while the Earthshaker carriage best filled the 155mm rolls

azimaith
25-10-2007, 23:13
I am trying to make an Imperial Guard army as real as i possibly can make it and a few questions have come to the front. What would the real world equivalent be to some 40k weapons?

Right now I'm primarily focusing on an artillery battalion so here are my suggestions or match ups and i would like to see if people agree or not.

Imperial Heavy Mortar = 105mm Howitzer : http://www.forgeworld.co.uk/heavymort.htm
Heavy Artillery carriage with Earthshaker Cannon = 155mm Howitzer: http://www.forgeworld.co.uk/acatalog/DEATH_KORPS_OF_KRIEG.html

You know i'd hazard to say that 12's are more like basilisks than 155's. 155's are more like Medusas, while Heavy mortars are closer to 105s. (I'm excluding little david because its old.)




Heavy Weapons:

Heavy Bolter: 30mm Infantry machine gun (a bit of a stretch)
Autocannon: 50 cal Heavy machine gun

The heavy bolter is really much closer to a .50 than a 30mm considering that autocannons fire larger rounds and a 30mm is something like 2x as large as a .50. Besides, 30mms are often called "autocannon".

carl
25-10-2007, 23:15
What I am looking for is something that would fill the roll of the 105mm Howitzer

Argete's list is good then.


Las pistol - 9mm side arm
Las Gun - Basic Infantry Rifle
Heavy Stubber - 5.56mm LMG like the M249 Saw
Heavy Bolter - 7.62mm MMG like the M60/M240B
Autocannon - .50cal HMG like the Browning M2 "Ma Deuce"
Missle Launcher - AT-4 or equvilant
Multi-lasers and Lascannon - we'll these start to get really screwy. and nothing truely fits here in RL comparison
Assault Cannon- 5.56mm Electric gatling gun.
Think thats most of the Infantry weapons that aren't obvious

Vehicles
Sentinals - Jeep/Humvee (yes I know they aren't walkers)
Chimera hulls - M113/Bradleys and varients
Leman Russ - Any MBT.


The heavy bolter is really much closer to a .50 than a 30mm considering that autocannons fire larger rounds and a 30mm is something like 2x as large as a .50. Besides, 30mms are often called "autocannon".

From a RL equivelent yes. From an actual stated statistic fior the Heavy Bolter, NO. The Heavy Bolter IS 30mm calibre, the Autcannon is thierfore somwhere well above it, (unless it's got an improbably powerful type of ammo and a stupidly long barrel).

Omniassiah
26-10-2007, 00:41
Yeah thats pretty close Krag, would be about right.

Templar Ben
26-10-2007, 00:47
You meant to say, "way to small." There are pistols that chamber .50 rounds, and I have yet to meet a non-man portable pistol.

There is a world of difference in a .50 AE and a .50 BMG.

Orcboy_Phil
26-10-2007, 00:50
Shells designed to penetrate armor and then explode inside the target have existed since the early 20th century. They haven't been called "mass reactive" (a silly term anyway), but the technology is nothing exotic.

I'm not sure what your talking about here. There are rounds that certainly penetrate armour, and there are ones that expand (not explode) upon impact (Hollow points or Dum Dum's) but I've never hears of a bullet that does both outside of Sci Fi. Could you please provide referances?

Also I think that debate is kinda moot. The Imp Guard, in design and look, are based upon First and Second world war style weaponary. A period when unfeassible large guns where put upon armoured chassis and used. However these designs are now known to be both impratically and rather unweildly in application.

azimaith
26-10-2007, 00:50
Indeed, the .50 is merely the width of the bullet, not the length or amount of propellent in the casing. One wouldn't argue that a .45, being but .05 under .50 is as powerful as a 50 cal machine gun.

I'm not sure what your talking about here. There are rounds that certainly penetrate armour, and there are ones that expand (not explode) upon impact (Hollow points or Dum Dum's) but I've never hears of a bullet that does both outside of Sci Fi. Could you please provide referances?

There are, they're often referred to as "Blended metal rounds" which basically explosively unmake themselves when they hit soft tissue. They can thus penetrate an 1/4 steel plate then impact a soft target behind and explode catastrophically. In fact the first casualty from these weapons occured on an oil rig where a navy seal killed an enemy combatant with a shot in the buttocks, something thats not normally fatal. You can also look up other variations of frangibles. In addition there are other rounds that work on different principles that have been around for a long time.

For frangible style rounds its generally designed to prevent overpenetration so it doesn't strike a non-combatant behind a combatant. For blended metal rounds they also explode after penetrating when they strike dry wall as well.

http://armedforcesjournal.com/blackwater/?s=2004_videos
Look here for the .45 ACP (as in the hand gun) vs meat test and then tell me we don't have exploding bullets.

Omniassiah
26-10-2007, 01:47
Frangibles don't exactly explode as much disintegrate.

@Carl - One thing that we must realize is how ineffective Bolt rounds are. Generally speaking the US Army liked the 5.56 round because a soldier could carry more of it. By fluff most SMs put movies to shame with the amount of ammo they mystically are able to shoot. At 20 rounds per magazine you'd need at least 10+1 for a full combat load. Thats 220 rounds which is not going to last in most fights. Most soldiers my self included will carry at least double or triple your combat load so which I would expect most Space Marines to carry because of their general role on combat That gives you say 36+1. so at 5 pounds per mag which is extremely conservative(I'd wager closer to 7-10lbs+) so 180 pounds just in ammo for a bolter. That said I can reproduce similar results with a 7.62mm AR firing Tungsten Carbide Armor Penetrators at a much higher muzzle velocity which would more and likely have a far superior range and armor penetration value(the shape of the Bolt round and subsonic speed would actually inhibit Armor penetrating power).

One of the Great myths of weapons is that bigger caliber is better and adding explosives makes it perfect. But when you look at all the current High damage weapons its the opposite... Small diameter, High velocity rounds made out of a very dense material. If you want to rip through a armor vehicle you wouldn't use a large, low muzzle velocity weapon, you'd want a Small, High-velocity weapon firing dense armor penetrators like a 5.56mm Electric gatling gun or perhaps a larger 7.62mm Electric gatling. Which has the nice benefit of being able to carry the massive 20-40k round ammo drums that would be required for such a High cyclic rate weapon with out being to large and bulky to be practical. You'd be surprised what you can do with a small round.

Argastes
26-10-2007, 02:03
That’s why I mentioned the predator, First and foremost, remember the Heavy Bolter fire rocket assisted rounds, their is absolutely no reason therefore why a heavy bolter would be ANY less powerful than a contemporary 30mm long barrelled cannon like the various Orlerkien Models, (pardon the spelling please).

Umm yes, there is such a reason: Bolt ammunition of all types is portrayed as short and stubby, with a LOA of no more than about three times the weapon's caliber. This translates to relatively low muzzle velocity (probably faster than a 40x53mmSR grenade as used in the Mk.19 but slower than a 30x113mm Aden/DEFA cannon round as used in the M230) regardless of whether rocket propulsion or conventional propulsion is used. Whereas a bottle-necked long-cased cannon shell of the modern type (and the type used in autocannons has at least TWICE as much propellant behind it.

Let's compare a 30mm cannon shell with proportions similar to a heavy bolter shell, and a 30mm cannon shell with proportions similar to an autocannon shell. We'll use the 30x113mm shell as a modern analog to the HB shell, and a 30x173mm shell as a modern analog to the AC shell. Even this comparison is probably going to exaggerate the power of the HB shell, because in all pictures and descriptions, HB shells are even stubbier than a 30x113mm shell.

A 30x113mm cartridge, loaded with the American-issue HEI projectile, fires a 237-gram shell at 800 meters per second, developing 75,800 joules of muzzle energy. A 30x173mm cartridge, loaded with the American uranium-cored API projectile, fires a 425-gram shell at 988 meters per second, developing 210,000 joules of energy. So the latter (autocannon-equivalent) is nearly three times as powerful as the former (theoretical heavy bolter equivalent) despite being of the same caliber. The comparison becomes even more compelling when you consider that even a 30x113mm cartridge is significantly longer than a heavy bolter cartridge, if we take the artwork and descriptions to be accurate, so a heavy bolter shell would actually develop even less energy. Based on a scaling of 30x113mm performance to match a round with a cartridge LOA of maybe 30% less (which is about what a heavy bolter shell looks to be), we get a velocity of maybe 600 meters per second, which would give 44,600 joules of energy.... making the 30x173mm shell (autocannon equivalent) nearly FIVE TIMES more powerful. Even if an autocannon was "only" of 25mm caliber--say, equivalent to a modern 25x137mm cannon (131,000 joules of energy with APFSDS ammo)--it would still be TWICE as powerful as a heavy bolter, despite being of smaller caliber. Is that enough difference to account for two points of strength with no change in AP? I think so.


Add to that that we know from fluff sources that the Autocannon is about the same fire rate as a heavy bolter, (fully automatic and faster than a man can pull the trigger, but not up to the standard of multi-barrel cannon or small calibre machine guns), we can dismiss the "high S is cause of multiple shots" theory for the mot part.

I didn't apply that argument to the autocannon, I applied it to the assault cannon. Although actually, you could still apply it to the autocannon vs. HB question, despite what you just said. If they're "about the same rate of fire", why does the HB get 50% more shots? If you're correct and they're about the same rate of fire, then the autocannon's higher strength and fewer shots COULD be explained by the theory that it's multiple "real" shots are lumped together to give a smaller number of stronger "game" shots. The reason I don't really want to seriously make that argument is because your starting premise (that the autocannon and heavy bolter have similar cyclic rates) is questionable. They both fire faster than a man can squeeze off single shots and slower than multi-barreled weapons, but that doesn't prove their rates of fire are even roughly equivalent; because between those upper and lower bounds is a very large range of cyclic rates. 400 RPM and 1200 RPM both fit within those bounds, but obviously one is a Mk.19's slow thump-thump-thump and one is an MG-42's buzzsaw scream. I think that since an HB gets 3 shots and an autocannon gets 2, and neither weapon's Strength value seems to represent "shot lumping", it's safe to assume that the HB develops a somewhat faster rate of fire.


The simple fact is where dealing with a weapon vastly more powerful than a standard modern 30mm cannon. Unless your suggesting a stupidly long barrel and stupidly high barrel pressures then we can confidently say it is vastly larger than 30m, not to mention that the Artwork, (for the most part), isn't done in heroic scale, and that DOES show it as large calibre too.

No, we aren't necessarily dealing with such a weapon at all, for the reasons explained above. Heavy bolters can be assumed to develop fairly low muzzle velocities, whereas an autocannon seems to develop quite high muzzle velocities. There's no need to explain an autocannon's higher strength with a "vastly larger" caliber, especially when such an explanation would then raise the question of why two men can haul such a massive gun around the battlefield on what's basically a DShK carriage.

And yeah, much of the artwork IS done in heroic scale. For example, despite the established fact that a boltgun shell is EXACTLY 0.75 inches (19.05 millimeters) in caliber, artwork regularly shows boltguns with muzzles which indicate a much larger caliber--even the comparatively realistic, well-proportioned artwork does this. So even where artwork isn't generally disproportionate, it's portrayal of details like gun bore diameters often is. Nevertheless, if you cite me a specific piece of artwork (book and page number) which clearly shows an autocannon muzzle, with a nearby object of known size by which to establish scale, I'll consider the argument.


And no 57mm ammo isn't 2ft long, its however long you bloody well make it, but you completely skipped the short barrel low pressure statements I gave which would explain that to you quite clearly.

No, I didn't skip it, I addressed it by pointing out that a 57mm cannon, even with a greatly shortened barrel, would be far too bulky and heavy to be moved around by a two-man crew (not to mention that the IG autocannon models do NOT have thick, stubby barrels which would indicate a sawed-off 57mm gun). I even linked you to pics showing just how massive a 57mm gun is even if you don't consider the barrel--go back to those pics and look at the actions of the guns, ignoring the barrels. To make it even more clear, let me point out that even the lightest 57mm cannons weigh more than half a ton, with 700-900 kg being more common. And that's without any mounting hardware or feed mechanism. Trust me, there is a GOOD reason that 57mm automatic cannons are only mounted on warships, armored vehicles, and heavy-duty four-wheeled carriages. Even with no barrel (let alone a barrel that was only shortened) they would still be much too heavy for a mounting of the type used by IG autocannon teams.


With low barrel pressure and a short length barrel you need far less gas from the cartridge, that means a MUCH smaller cartridge section and a much smaller breach and barrel with much thinner materials being involved since it doesn’t need to be as strong because of the lower pressures.

The weapon won't have the range or punch of a proper 57mm, but the large size of the ammo will still make it pretty evil to whatever it hits.

But now you're describing a weapon which is more like an overgrown automatic grenade launcher firing very low-velocity shells, which doesn't make sense given that the autocannon is a long-ranged direct-fire weapon--and that the 2nd edition wargear book explicitly says it fires "high-velocity" shells. It also doesn't make sense because this theoretical 57mm low-pressure gun is a radically different weapon from the long-barreled, apparently high-velocity gun mounted on the Predator, Leman Russ Exterminator, etc.--yet they share the exact same statline.

Whatever description of an autocannon we come up with, it must convincingly describe both a Predator's main gun AND the weapon carried around by IG heavy weapons teams. A 25mm high-velocity cannon does that, because it is both a satisfactory armament for a medium armored vehicle, and could be moved around by a two-man team if fitted with a lightweight feed system and a cleverly designed mount and carriage. A 57mm overgrown AGL does not fit the bill at all.


The assault cannon and the GAU-8 share 1 simple point, their multi-barrel cannon firing huge amounts of large calibre rounds at the opposition.

But DOES an assault cannon fire "large caliber rounds"? No! At least not nearly as large as those fired by the GAU-8. Each GAU-8 round is about the size of a milk bottle, meaning that a terminator--or even a dreadnaught--could never carry enough of an ammunition supply to fire anything more than a single short burst given the assault cannon's ultra-high cyclic rate.


And on top of that you really should try to remembers that GW just doesn’t give a damm about what’s possible, fluff wise the Assault cannon has all the effects of a GAU-8 on it's targets, right down to chewing up MBT's. Even I can't figure out a realistic way to make that work, but that’s what it can do and thus the real world equivalent IS the GAU-8, no matter how littlie sense it makes.

No. This is just plain wrong. An assault cannon does NOT have all the effects of a GAU-8, either in fluff or in rules. Fluff-wise, I defy you to find me even a single piece of fluff in which an assault cannon is described as having effects on an MBT that are even close to those of a GAU-8. Rules-wise, let's review: When you fire an assault cannon, there is a chance (a chance, not a guarantee) that one (probably no more than one) of the shots will get an additional penetration die, which may or may not result in penetration (probable but not guaranteed), and if it does penetrate, this may or may not result in the destruction of the target (50% chance). When you do the math, we find that firing an assault cannon at a heavy tank is only going to result in the target's destruction in a minority of cases--something which any SM player could tell you anyway. Despite it's ability to take out a tank, an assault cannon is not a reliable tank-buster--it can do the job sometimes, but not in most cases.

On the other hand, hitting a tank with a burst from a GAU-8 is pretty much 100% effective. If it hits, the tank is gone. End of story. Each round from a GAU-8 is pretty much guaranteed to pierce even a heavy tank's armor (the DPU round will penetrate eight inches of RHA)--in fact, the rounds often go in one side and out the other, meaning they have enough energy to penetrate a heavy tank's armor TWICE! And due to the pyrophoric effect of depleted uranium, each round does so much damage inside that the tank will almost certainly be destroyed by even one of these projectiles; and a tank which is hit by a burst is probably going to be struck by dozens of individual rounds! And since a GAU-8's shell can penetrate even a heavy tank's armor, it would have no problem punching straight through power armor or terminator armor--yet an assault cannon allows this armor to take it's full save, and can only defeat carapace/'ardboy armor or worse.

If you think an assault cannon has the same effects as a GAU-8 on tanks, or other targets, you simply have no idea what kind of effects a GAU-8 really has. I repeat: If a GAU-8 or something equivalent was represented in game, it would have to be S10, because even a single round from it is capable of going through BOTH sides of an MBT or blasting a monstrous creature's guts out. Unless an assault cannon turns Land Raiders into Swiss cheese EVERY TIME it fires at them, it's not equivalent to a GAU-8. It's not even close.


I'm not sure what your talking about here. There are rounds that certainly penetrate armour, and there are ones that expand (not explode) upon impact (Hollow points or Dum Dum's) but I've never hears of a bullet that does both outside of Sci Fi. Could you please provide referances?

I'm talking about delayed-impact fuzes, typically base fuzes (meaning they are fitted into the rear of the projectile rather than the nose), which have been in use since soon after the introduction of modern breech-loaded artillery and were developed for shells designed to engage armored targets such as warships and concrete fortifications. Sorry, I should have made it clear that I wasn't talking only about small arms ammunition. It's true that such fuzes have never been fitted to small arms ammunition, but that doesn't mean they couldn't be. It wouldn't be hard to miniaturize the necessary components; such miniaturization is easily possible today, it's just that no-one bothers because there's currently no application for exploding small arms ammunition.


Also I think that debate is kinda moot. The Imp Guard, in design and look, are based upon First and Second world war style weaponary. A period when unfeassible large guns where put upon armoured chassis and used. However these designs are now known to be both impratically and rather unweildly in application.

:confused: What was unfeasible about the guns used on armored vehicles of those wars? Tank guns today are even larger, and are still perfectly feasible and practical. In fact, the current trend is towards even larger tank guns--the next generation of MBTs may well use guns in the 140mm range rather than 120-125mm. The designs of WW1 and WW2 are not at all known to be impractical and unwieldy today.

azimaith
26-10-2007, 02:45
Frangibles don't exactly explode as much disintegrate.

The frangible part of blended metal ammunition is only the way it stops in soft materials to prevent over-penetration. Blended metal frangibles most certainly do explode, they just don't utilize and seperate fuzes.



I'm talking about delayed-impact fuzes, typically base fuzes (meaning they are fitted into the rear of the projectile rather than the nose), which have been in use since soon after the introduction of modern breech-loaded artillery and were developed for shells designed to engage armored targets such as warships and concrete fortifications. Sorry, I should have made it clear that I wasn't talking only about small arms ammunition. It's true that such fuzes have never been fitted to small arms ammunition, but that doesn't mean they couldn't be.

And it doesn't mean that they can't still explode as per my above linked video with the .45 blended metal.



It wouldn't be hard to miniaturize the necessary components; such miniaturization is easily possible today, it's just that no-one bothers because there's currently no application for exploding small arms ammunition.

Well thats not entirely accurate, many groups are looking for more lethal ammunition that doesn't overpenetrate or require lots of special training to use.
Its used by special forces teams and if I recall correctly, the FBI is currently looking into starting to use Blended Metal rounds.

Argastes
26-10-2007, 03:07
Yeah, I'm familiar with the blended metal rounds, but no, they don't explode. They disintegrate. And yes, they disintegrate in a fashion which creates wound trauma more severe than that associated with traditional ammunition of the same caliber--but they still don't explode. In firearms terminology, a projectile doesn't explode unless it is broken into fragments by the detonation of an explosive composition inside the body of the projectile. A bullet which fragments so effectively that it "practically explodes" still doesn't actually explode. Blended metal projectiles aren't unique in their wounding mechanism; they do the same thing that previous frangible bullets have done. They just do it better, by virtue of more advanced design.

azimaith
26-10-2007, 03:10
Practically explodes and explodes means the same thing to the guy whose had his internal organs pureed. I don't think its very important whether they "technically" explode so long as the provide the same effect and description as a round that would explode.

I'd go with the more conventional definition:
1. to expand with force and noise because of rapid chemical change or decomposition, as gunpowder or nitroglycerine (opposed to implode).
2. to burst, fly into pieces, or break up violently with a loud report, as a boiler from excessive pressure of steam
They expand with force and noise because of a chemical change. Good enough for me.

Argastes
26-10-2007, 03:25
Practically explodes and explodes means the same thing to the guy whose had his internal organs pureed. I don't think its very important whether they "technically" explode so long as the provide the same effect and description as a round that would explode.

I'd go with the more conventional definition:
1. to expand with force and noise because of rapid chemical change or decomposition, as gunpowder or nitroglycerine (opposed to implode).
2. to burst, fly into pieces, or break up violently with a loud report, as a boiler from excessive pressure of steam
They expand with force and noise because of a chemical change. Good enough for me.

As I understand it, they disintegrate because changing thermal conditions inside the target change the physical behavior of the materials in the bullet's composition, so it's not a chemical change, it's a physical change--no chemical reaction occurs. If expanding due to physical change makes a round "explosive", then current frangible bullets are "explosive" too. I appreciate that the technical meaning of the word "explosive" may not matter to the guy who got shot, but we're not the guy who got shot--we're guys on a forum discussing firearms. An especially well-designed frangible bullet is not explosive no matter how much damage it does inside a person. We should use correct terminology. You don't have to think the difference is important, but saying "explosive bullets already exist for small arms" on the basis of blended metal rounds is simply not correct. For blended metal rounds, "explosive" is a misnomer. The effects may be similar, but the mechanism by which those effects are achieved is not.

Put it this way: I've shot deer with a 7mm Remington Magnum (too much gun for whitetail, I know) ballistic-tipped hollowpoint which produced tissue damage comparable to (if not superior to) that of these new blended-metal rounds; does that mean that ballistic-tipped hollowpoints are "explosive" rounds too, since they also produce comparable damage to a true explosive round? Of course not. Explosive rounds are those that explode, and only those that explode.

And lastly, I have to point out that just because these blended metal rounds do a lot of damage inside the target DOESN'T mean they provide the same effect as explosive rounds. An explosive bullet, while it might inflict a comparable "amount" of damage (assuming you could quantify a thing like that...), might not inflict it in exactly the same way. With an explosive bullet, I'd expect to see a more prolate permanent wound cavity with multiple small wound tracks radiating from it, and sharper hydrostatic shock effects.

Sekhmet
26-10-2007, 03:44
I'm talking about delayed-impact fuzes, typically base fuzes (meaning they are fitted into the rear of the projectile rather than the nose), which have been in use since soon after the introduction of modern breech-loaded artillery and were developed for shells designed to engage armored targets such as warships and concrete fortifications. Sorry, I should have made it clear that I wasn't talking only about small arms ammunition. It's true that such fuzes have never been fitted to small arms ammunition, but that doesn't mean they couldn't be. It wouldn't be hard to miniaturize the necessary components; such miniaturization is easily possible today, it's just that no-one bothers because there's currently no application for exploding small arms ammunition.

Actually... that's wrong. No one bothers not because there's no application for exploding small arms, but because they're banned in warfare by international convention. Hollow point rounds are also banned in warfare. Against human targets. That's why you get HEAP .50 rounds, they're used as anti-material.

Police actions are not war, however.

azimaith
26-10-2007, 04:02
As I understand it, they disintegrate because changing thermal conditions inside the target change the physical behavior of the materials in the bullet's composition, so it's not a chemical change, it's a physical change--no chemical reaction occurs.

They "Unmake" themselves due to changes in temperature in the target. That is a chemical change as it releases a large amount of energy in the reverse process. Its not the same thing as breaking a bullet (like a frangible) or simply deforming(like a hollow point.) Theres chemical energy pent up in that round which essentially explosively releases itself at a temperature equivalent to a bullet entering a material like flesh or dry wall.



If expanding due to physical change makes a round "explosive", then current frangible bullets are "explosive" too. I appreciate that the technical meaning of the word "explosive" may not matter to the guy who got shot, but we're not the guy who got shot--we're guys on a forum discussing firearms.

Explosive in the common sense is applied to both physical and chemical changes. If you take a canister and overfill until it bursts open, it would be considered an "explosion". An explosion is simply a violent, fast reaction that results in an object breaking apart and releasing energy.



An especially well-designed frangible bullet is not explosive no matter how much damage it does inside a person. We should use correct terminology. You don't have to think the difference is important, but saying "explosive bullets already exist for small arms" on the basis of blended metal rounds is simply not correct. For blended metal rounds, "explosive" is a misnomer. The effects may be similar, but the mechanism by which those effects are achieved is not.

Fine, explosive equivalent, its irrelevent because it accomplishes the same result as a bolt-gun which was the original assertation. We have bolt-round equivalents today for small arms.



Put it this way: I've shot deer with a 7mm Remington Magnum (too much gun for whitetail, I know) ballistic-tipped hollowpoint which produced tissue damage comparable to (if not superior to) that of these new blended-metal rounds; does that mean that ballistic-tipped hollowpoints are "explosive" rounds too, since they also produce comparable damage to a true explosive round? Of course not. Explosive rounds are those that explode, and only those that explode.

Did you look at what the blended metal round did?
Certainly a JHP round will cause a massive ragged wound and it may even cause an explosive like effect due to its massive energy transfer, but the difference is the JHP transfers on impact and its kinetic energy from the rounds chemical propulsion. The Blended metal transfers both kinetic impact energy and energy from the bullet itself after its entered the target making it "Explosive". The JHP round doesn't blast itself apart, it may break, but it doesn't do the same thing a blended metal does thus isn't in the same running. The part that makes the blended metal "explosive equivalent" is that the payload actually blasts itself apart by its chemical composition, which the JHP does not.



And lastly, I have to point out that just because these blended metal rounds do a lot of damage inside the target DOESN'T mean they provide the same effect as explosive rounds. An explosive bullet, while it might inflict a comparable "amount" of damage (assuming you could quantify a thing like that...), might not inflict it in exactly the same way. With an explosive bullet, I'd expect to see a more prolate permanent wound cavity with multiple small wound tracks radiating from it, and sharper hydrostatic shock effects.
Fragmentary secondary effects aren't very important to deciding whether its explosive equivalent or not, if you decided to add fragmentation to a Blended metal you could achieve the same effects.

Eisen
26-10-2007, 04:15
They "Unmake" themselves due to changes in temperature in the target. That is a chemical change as it releases a large amount of energy in the reverse process. Its not the same thing as breaking a bullet (like a frangible) or simply deforming(like a hollow point.) Theres chemical energy pent up in that round which essentially explosively releases itself at a temperature equivalent to a bullet entering a material like flesh or dry wall.

I had planned to stay out of this thread... but... no.

Temperature change is a physical process, not a chemical. It affects the structural characteristics of the object in ways that chemical processes do not, and is purely physical in nature. While some chemical reactions are endothermic, and most are exothermic, temperature change by itself is purely physical.


Explosive in the common sense is applied to both physical and chemical changes. If you take a canister and overfill until it bursts open, it would be considered an "explosion". An explosion is simply a violent, fast reaction that results in an object breaking apart and releasing energy.

The canister is not actually exploding per se; it is being strained past its yield point by excessive interior pressure. The mechanism is different, though the effects are the same.


Fragmentary secondary effects aren't very important to deciding whether its explosive equivalent or not, if you decided to add fragmentation to a Blended metal you could achieve the same effects.

... But what you're describing for a blended-metal round is fragmentation, the same way your exploding scuba tank earlier was fragmenting, not explosion. The effect is not caused by a sudden extremely exothermic chemical reaction, it is caused by a rapid and intolerable change in stress states for the material, straining the material beyond its limit and causing catastrophic failure.

Before anyone decides that I'm nitpicking - I agree, anything that releases a cloud of microfragments inside a target, be it armored vehicles taking spall or punching through a kevlar vest to burst inside the body might as well be an explosion. It's not, but it's the same way that stress from thermal expansion can be expressed the same way as stress from an object just leaning on it.

Now, back to lurking - because, honestly, debating realistic weapon performance in 40k is like putting roofing on a tent - difficult, unlikely to produce a good result, and likely to make you punch your living space full of needless holes.

Argastes
26-10-2007, 04:47
They "Unmake" themselves due to changes in temperature in the target. That is a chemical change as it releases a large amount of energy in the reverse process. Its not the same thing as breaking a bullet (like a frangible) or simply deforming(like a hollow point.) Theres chemical energy pent up in that round which essentially explosively releases itself at a temperature equivalent to a bullet entering a material like flesh or dry wall.

I'm sorry, but that's just not true. The bullets are composed of molded and sintered metallic powders which become de-sintered under thermal stress, causing them to disintegrate rapidly. That is a PHYSICAL change. No chemical change occurs and no chemical energy is released. They break up due to physical stresses on the round, not a chemical change--just like other frangible bullets. What makes them special is that the physical stress which causes them to break up is not experienced when passing through armor materials (meaning they can hold together while penetrating armor, then break up in flesh) and that they break up in a fashion which inflicts more wound trauma than normal frangible bullets.


Explosive in the common sense is applied to both physical and chemical changes. If you take a canister and overfill until it bursts open, it would be considered an "explosion". An explosion is simply a violent, fast reaction that results in an object breaking apart and releasing energy.

Right, I agree that that's what "explosive" means in the common sense. But this is a discussion about firearms, not overfilled canisters. We should use terms according to their meaning in firearms terminology, not in the common sense. I repeat: If bursting apart violently due to physical change is "explosive", then conventional fragmenting bullets are "explosive bullets" too, because that's exactly what they do.

I realize that the guy who insists on proper terminology can seem like a hair-splitting pain in the butt. But if you use sloppy terminology in a technical discussion, then the end result is misleading statements. Does a man with 1,000 tons of TNT have a 1-kiloton nuclear bomb? No, and it would be misleading to say that he does. To be accurate, you should say that "he has explosives comparable in power to a 1-kiloton nuke", not just "he has a 1-kiloton nuke". In this case, you told Orcboy Phil that we have exploding small-arms ammunition today, when in fact we have advanced frangible ammunition that is only similar in effect to exploding ammunition. Whether or not you think the difference is irrelevant, the upshot is that if I hadn't stepped in and corrected your terminology, Orcboy Phil might have gone on his merry way believing that we have explosive small arms ammunition, instead of just a rough equivalent.


Fine, explosive equivalent, its irrelevent because it accomplishes the same result as a bolt-gun which was the original assertation. We have bolt-round equivalents today for small arms.

Okay, this is fine. Using technologies which create an effect similar to explosive bullets, we can create a weapon which has an effect similar to that of a boltgun. I have no problem with that statement, because it doesn't claim that "similar" is just the same as "identical".


Did you look at what the blended metal round did?
Certainly a JHP round will cause a massive ragged wound and it may even cause an explosive like effect due to its massive energy transfer, but the difference is the JHP transfers on impact and its kinetic energy from the rounds chemical propulsion. The Blended metal transfers both kinetic impact energy and energy from the bullet itself after its entered the target making it "Explosive". The JHP round doesn't blast itself apart, it may break, but it doesn't do the same thing a blended metal does thus isn't in the same running. The part that makes the blended metal "explosive equivalent" is that the payload actually blasts itself apart by its chemical composition, which the JHP does not.

No, again, this isn't supported by descriptions of how the round functions. The round functions by virtue of the fact that it's pressed and sintered together, and that the resultant physical--not chemical--bonds between the metal particles are broken by thermal stress created by passage through the target. All the energy involved is still the kinetic energy added to the bullet by the gunpowder that launched it from the barrel. The round seems to "burst" apart because it's constituent particles all come unglued from each other simultaneously due to thermal stress, rather than piecemeal due to impact stress (as is the case with conventional frangibles). But the energy which causes those particles to scatter through the target medium once they become unglued is still 100% provided by the bullet's kinetic energy, not additional energy released from within the bullet.


Fragmentary secondary effects aren't very important to deciding whether its explosive equivalent or not, if you decided to add fragmentation to a Blended metal you could achieve the same effects.

Whether it would be possible to add fragmentation effects to a blended metal bullet is questionable. How would you achieve this? By coating the bullet in a jacket of material which does not possess the thermally-activated frangible qualities of the blended metal material? This might do more harm than good for the projectile's wounding effects, because the force which causes the bullet to "burst" apart once disintegrated by thermal stress is still resistance from the target medium. A blended metal bullet with a fragmentation jacket might disintegrate under thermal stress as normal, but then fail to achieve the "explosive" bursting effect because of the presence of the fragmentation jacket preventing it from breaking up against the target medium. This is speculative, but the point is that you are not a ballistics expert who has practical experience with blended metal bullets, so you should not be so confident in declaring "you could add fragmentation effects to the blended metal bullets if you wanted to." Maybe you could, maybe not. Given that the bullet is not "burst" by a force originating from within the bullet itself, it seems doubtful. And then there's the other factor I mentioned, hydrostatic shock (another misnomer, but this one has entered common circulation in the field of terminal ballistics, so whatever...). Even if you could somehow add fragmentation effects to a blended metal bullet, there seems to be very little possibility of also adding the unusually severe hydrostatic shock effects that an explosive bullet would create. So bottom line, an explosive bullet may well possess wounding properties beyond the capabilities of the blended metal bullets. This isn't to say that explosive bullets are "better", but you should be careful about declaring, as if you were an authority, that blended metal bullets could be made to imitate any characteristic of explosive bullets and thus would always be equivalent to them.

EDIT: And as I do more and more reading into blended metal bullets, as a result of this discussion, the veracity of Le Mas' claims is starting to look more and more questionable. They don't have a patent, or an application pending, as far as I can tell. The story of the Navy SEAL blowing a guy's ass open seems to be just another interweb urban legend--no source, no backing. They guy who runs Le Mas keeps refusing to provide ammunition for independent testing, refusing to provide the names of the engineers who developed it, refusing everything that might help verify his claims about the ammo's effect. Oh, and the pics on his website show perfectly traditional copper-jacked LRN (lead round nose) bullets.... WTF? I think this whole thing is a sham.

Eisen
26-10-2007, 04:59
Back again.


Whether it would be possible to add fragmentation effects to a blended metal bullet is questionable. How would you achieve this? By coating the bullet in a jacket of material which does not possess the thermally-activated frangible qualities of the blended metal material? This might do more harm than good for the projectile's wounding effects, because the force which causes the bullet to "burst" apart once disintegrated by thermal stress is still resistance from the target medium. A blended metal bullet with a fragmentation jacket might disintegrate under thermal stress as normal, but then fail to achieve the "explosive" bursting effect because of the presence of the fragmentation jacket preventing it from breaking up against the target medium. This is speculative, but the point is that you are not a ballistics expert who has practical experience with blended metal bullets, so you should not be so confident in declaring "you could add fragmentation effects to the blended metal bullets if you wanted to." Maybe you could, maybe not. Given that the bullet is not "burst" by a force originating from within the bullet itself, it seems doubtful. And then there's the other factor I mentioned, hydrostatic shock (another misnomer, but this one has entered common circulation in the field of terminal ballistics, so whatever...). Even if you could somehow add fragmentation effects to a blended metal bullet, there seems to be very little possibility of also adding the unusually severe hydrostatic shock effects that an explosive bullet would create. So bottom line, an explosive bullet may well possess wounding properties beyond the capabilities of the blended metal bullets. This isn't to say that explosive bullets are "better", but you should be careful about declaring, as if you were an authority, that blended metal bullets could be made to imitate any characteristic of explosive bullets and thus would always be equivalent to them.

Actually, it'd be damn near impossible to add a fragmentation jacket to a blended round, because the frag jacket itself changes the thermal characteristics of the reaction. The frag jacket absorbs a lot of the heat, and places a confining stress on the core round. The result is a round that will behave in a fragmentary manner, then come clean out the other side... and, upon exposure to air, continue on to whatever warm body it finds before disintegrating. And that doesn't even take into account the interface layer between frag jacket and core - God knows what that thin layer of epoxy or what-have-you is going to do; probably not much, but this entire process has to take place in the time it takes for a round to punch through a body, so the tolerances aren't that great before the reaction's thrown off. That brings up another problem with explosive penetrating rounds - getting them to explode when you want them to, not when they've overpenetrated, harmlessly in midair.

Argastes
26-10-2007, 05:22
Back again.

Actually, it'd be damn near impossible to add a fragmentation jacket to a blended round, because the frag jacket itself changes the thermal characteristics of the reaction. The frag jacket absorbs a lot of the heat, and places a confining stress on the core round. The result is a round that will behave in a fragmentary manner, then come clean out the other side... and, upon exposure to air, continue on to whatever warm body it finds before disintegrating. And that doesn't even take into account the interface layer between frag jacket and core - God knows what that thin layer of epoxy or what-have-you is going to do; probably not much, but this entire process has to take place in the time it takes for a round to punch through a body, so the tolerances aren't that great before the reaction's thrown off. That brings up another problem with explosive penetrating rounds - getting them to explode when you want them to, not when they've overpenetrated, harmlessly in midair.

A good point. However, in the end, it may all be academic, because it now looks like blended metal bullets, with their "smart materials" and "programmable heat-sensing" gobbledygook, are an out-and-out fraud. There is zero independent, reputable testing to confirm this stuff's effectiveness, despite the fact that LML has been pushing it for like five years. The company owner, Stan Bulmer, refuses to do anything that might expose his product to independent scrutiny. The military has tested it and rejected it, although completely unsupported rumors/claims continue to circulate to the effect that it's "secretly" in use with "unnamed special ops units"--as a gun nut who uses the internet to keep up with firearms news, believe me when I say I've heard this one before! It's the standard BS line whenever some fringe company with an unimpressive (if not outright fraudulent) product wants to talk up their stuff without having to cite any solid evidence of the product's quality or performance. Oh, and some ballistics guys did get a hold of a few of the "blended metal" rounds and sectioned them with a cutting tool--revealing plain old copper-jacketed LRN rounds with a nylon ball in the rear section of the bullet, under the jacket. This last part isn't actually surprising, because copper-jacketed LRN bullets are exactly what's shown on LML's own website despite all their pseudo-science jargon about blended metal technology!

azimaith
26-10-2007, 05:48
I had planned to stay out of this thread... but... no.

Temperature change is a physical process, not a chemical. It affects the structural characteristics of the object in ways that chemical processes do not, and is purely physical in nature. While some chemical reactions are endothermic, and most are exothermic, temperature change by itself is purely physical.

Temperature change can lead to chemical change, the rounds don't change temperature (well they do, but thats not what causes it), the point is with a temperature change it blasts itself apart much like a lit firecracker.



The canister is not actually exploding per se; it is being strained past its yield point by excessive interior pressure. The mechanism is different, though the effects are the same.

I'm not talking about technicality, if I wanted to I could dispute all sorts of things, i'm saying that is that conventionally,that would be described as "explosive" Explosive is a adjective that is applied to things outside of bullets.



... But what you're describing for a blended-metal round is fragmentation, the same way your exploding scuba tank earlier was fragmenting, not explosion. The effect is not caused by a sudden extremely exothermic chemical reaction, it is caused by a rapid and intolerable change in stress states for the material, straining the material beyond its limit and causing catastrophic failure.

Which is why I call it explosion equivalent. It does the same thing and results in the same mess, just in different methods. The technicality of it is irrelevent to me.



Before anyone decides that I'm nitpicking - I agree, anything that releases a cloud of microfragments inside a target, be it armored vehicles taking spall or punching through a kevlar vest to burst inside the body might as well be an explosion. It's not, but it's the same way that stress from thermal expansion can be expressed the same way as stress from an object just leaning on it.

The point is that its a bolter equivalent for small arms, which is what was asked.

Argastes
26-10-2007, 05:59
Temperature change can lead to chemical change, the rounds don't change temperature (well they do, but thats not what causes it), the point is with a temperature change it blasts itself apart much like a lit firecracker.

It's already been explained to you multiple times why this isn't true. No chemical change occurs in the blended metal rounds, and it doesn't "blast itself apart". It (allegedly) disintegrates under thermal stress and the resultant particles are dispersed by resistance in the target medium. What part don't you understand? Why do you keep insisting that chemical change occurs in these rounds when the change is purely physical? Did you not take high school chemistry? Because anyone who has taken a high school level chemistry course has been taught the difference between physical and chemical change.

Again, all academic since "blended metal" rounds are a fraud anyhow.... they don't "blast themselves" apart in the target for ANY reason, chemical OR physical. They don't work.

carl
26-10-2007, 13:10
All right this has gone totally off-topic so I’ll try to bring it back on topic.

@Omniassiah: The whole high velocity things is true of modern rounds, yes. It's not true of a universe where the standard rounds are HE, Frag, Shaped Chrge and the odd solid ballistic shot. Only DA-fused HE and AP solid shot care about velocity, the rest, (and frag, impact fused HE and shaped charge are the most common seemingly), just need to be made bigger to be made more dangerous. From what I can tell the IoM has either never heard of Sabot ammo, or it's so rare it doesn’t deserve a mention.

On Heavy Bolters, have you or Argastes actually read the fluff for blot weapons, nothing in that remotely indicates subsonic performance in the slightest. What the fluff is very clear on, (especially for the smaller Bolter), is that’s it's quite capable of punching clean through modern armoured vest equivalents before exploding and we know from both their explosive effects on people and their ability to blow fist sized holes out of Power Armour, (i.e. fist size holes in steel/ceramic composites), that they clearly have explosives, (and thus probably rocket propellants), that are vastly more powerful than anything we use today. Theirs nothing I can find that indicates a heavy bolter is not equivalent to a 30mm modern cannon, no matter how impossible it would be for us to make it.

And NO a 25mm high velocity cannon does not convincingly fulfil both roles in any way shape or form, it would be vastly outperformed by a heavy bolter and still wouldn't be man portable because of it's huge MV would need a weapon with a barrel in the same length range as a GAU-8, and as you pointed out that’s totally impractical for man portable purposes. Because of what we KNOW about a heavy bolter it just isn't physically possible to come up with a man portable high velocity cannon that’s more powerful, it's that simple.

If you want proof, look at the models again, they may be in heroic scale, but the shell size compared to the cartridge size is huge, and they should be in scale to each other, do the same for a GAU-8 or a modern 20mm cannon, the cartridge is tiny by comparison, (you could explain it away with higher energy propellants, but that really doesn’t make sense, the recoil on any large weapon would be unmanageable with it).

And actually I do have an idea of the effects of a GAU-8, I also have a damm good idea of the effects of an assault canon. First and foremost all weaponry in 40K is severely understated in it's rules effects, look no further than the ubiquous bolter for proof, rules wise a rapid firing SM with Bolter averages 22.22% kills against another marine in power armour. Fluff wise it's lethal better than 50% of the time.

And whilst I’m thankful for some outright tech figures on the GAU-8, your figures just shot yourself in the foot, I have a quotable source, (the WD with the AC list in it), that puts the Leman Russ Front armour, (i.e. AV14), at 20" of Steel/Ceramic Composite. In other words a GAU-8 firing at the front armour of a Leman Russ wouldn't even scratch it, whilst an assault cannon supposedly has a chance. I'll try to find a Fluff assault cannon quote, but don't hope too much, I don't tend to buy many BL books, just borrow them.

Your point on the Autocannon multiple shots was well made but I simplified, generally depending on the author, (and weather he's treating the Autocannon as a Heavy Stubber, (which I’m ignoring as it's totally at odds with the stats and supposed effects), style weapon or an actual cannon), the Heavy Bolter and Autocannon generally, (not exclusively), use the same descriptions for fire rate, their either described as very fast firing, (generalisation as again I don't have any suitable BL books to hand to quote), or (which fits HB ][ Stats and it's background better, (about 240RPM)), as slow boom-boom-boom style weapons. On the tabletop they get different fire rates so both are viable.

If you want a readily accessible artwork example of how big an Autocannon is, open the Apoc book and look at the very first drawing, (the page with the words APOCALYPSE on it with a Baneblade underneath), look at the Baneblade’s Autocannon, then compare it to the big gun, (and then do the same with the model to prove it isn't heroic scale). Considering we KNOW the LR battlecannon is 200mm and that the BB cannon is more powerful, (and thus probably larger), are you really telling me that gun is a 25mm weapon?

Which is where the real issue hits us. You CAN'T come up with a weapon that’s high velocity, packs the supposed destructive punch of an Autocannon and is still man portable AND a useful main weapon for a Leman Russ and Predator AND a Co-Axial for a Baneblade with an 8"+ main gun.

The simplest answer is to call the Autocannon a class of weapons that have the same rules on the tabletop as each other.

That would let us cut the calibre of the man portable version somewhat although we are limited partially by the need to remain better than the Heavy Bolter, (otherwise why would both exist in the same regiments). Still we could drop it down to a 40mm medium velocity cannon, sort of a cross breed between a high velocity cannon and a high velocity grenade launcher.

At the same time a larger calibre weapon for the Predator / Exterminator / BB which could easily be equal or in excess of 57mm.


And yes I do have an idea of the size of a normal 57mm weapon, I’m a bit of an avid geek on military tech myself, I believe it was the Russian L-60 57mm AAA gun you gave the pics of. It's in one of my books, (Artillery of the World). My point is a weapon doesn’t necessarily have to be that big, an AAA cannon uses a very long barrel and powerful powder charge to get the round high enough to hit the target.

An Autocannon doesn’t need that kind of length, (if you want proof, look at the Hydra, it uses faster firing, longer barrelled Autocannon for it's AAA weapons indicative IMHO that conventional Autocannon are well below the lengths, fire rates, and thus velocities of modern AAA weapons of the same calibre).

Omniassiah
26-10-2007, 17:18
I hate to tell you Carl but black library books as enjoyable as they are to read, From somebody who's been in the military and does Armorer work the authors make horrible fluff mistakes. A bolt rounds explosive component is tap water... Seriously Depleted Deuterium is water. The way their explosives work while nice is nothing close to realism, The books all describe non-shaped charges with shaped charged effects.

Don't even get me started on the vehicles of 40k, there must be a line of Guard Tank commanders to replace the ones that eat the breach every time the gun fires since they sit right inline on it. And I would expect the LR Battlecannon to be taking a reduction in bore size once they release a new model of it considering that it is currently larger then a BB Battlecannon. As they get better molding systems the tanks are starting to get trimmed down to the proper proportions. The autocannon on the Baneblade is closer to a 25mm round then a 57mm round by far as the baneblade cannon maybe pushing 200mm now instead of the 2000mm it was before. I would guess that the LR when it gets a model update will be closer to 120-150mm in cannon diameter if not smaller.

Armor wise a Leman Russ has 200mm of front armor according to IA:1 which is frankly a much more realistic number then the WD. The IA books are written by tread heads so the less silly stuff like 20" of armor don't get used because well it would make a LR even more impractical then it already is, and I'm talking raw space in the vehicle. To even make it remotely plausible as a real tank you need at least an extra inch per dimension(on the model) and the turret needs to be close to baneblade size. to allow for the gunner/loader/commander. and thats with out an additional foot thick of armor.

GW could go for paying a couple of experts or just some people with actually military experience for the background on some of the fluff. That said its fiction and well people like the big numbers when the effects provided don't require anywhere close to the scale of firepower shown. And people love explosive rounds... Sadly explosives are crap for penetrating armor. There is this lovely thing called whether or not a explosive is "tamped" (assuming I'm not butchering this really should call my Combat Engineer friends). Basically even a shaped charge is relatively ineffective unless it can be resisted via some method opposite of what your trying to destroy. Its why versus light armored stuff you use HEAP rounds and Heavy armored you use sabot rounds. Which by the way you want a truely effective Bolt round... Use a Copper self-forging armor penetrator now thats what you want on a Self propelled round that burns off most of its mass in flight.

As for a 25mm Cannon being man portable its actually quite possible. M2 .50cal has a muzzle velocityof 853.4 mps (2930 fps). and is fair not difficult to be mounted on a Tripod. Barret is working on the XM109 which is a 25mm sniper rifle and thats Bipod mounted, its not far fetched to say a tripod mounted cannon version could be applied to a tripod with easy. Would feel bad for the poor suckers lugging the ammo but the weapon system is very plausible for a tripod mount like the US M2 or Mk19(And the Mk19 has little to no recoil for the gun though don't fire it with a closed mouth it hurts your lungs).

As for the whole frangabiles debate, I've used them in Iraq when we got a hold of a case for house to house work(trying to avoid killing civilians or friendlies more then anything). They are great and suck at the same time. Against a Unarmored target its like taking a 5.56mm shotgun to the target location at near point blank range. Very similar to hollow point ammunition or "Mushrooming" ammo. Against anything with even mediocre armor there is about equal chance that the round will disintegrate before penetrating flesh. One of the old style Flak vests stopped a few rounds and that wasn't rated for protection from bullets. Explosive ammo creates a different wound profile all together and usually has a much larger entry wound and many smaller exit wounds from the explosive casement passing through the body. If you walked up on a 2 bodies shot by the 2 weapon systems you would be able to tell the difference with out any difficulty. Also almost all bullet wounds will cause a impact hit bulge from the displacement of the round on impact. And depending on the internal structures of the impact sight you can also get some bulge from the the non-linear travel of the bullet parts(bone ricochets, body density movement deviation, and any other weird things that happen.)

Sekhmet
26-10-2007, 17:39
And whilst Iím thankful for some outright tech figures on the GAU-8, your figures just shot yourself in the foot, I have a quotable source, (the WD with the AC list in it), that puts the Leman Russ Front armour, (i.e. AV14), at 20" of Steel/Ceramic Composite. In other words a GAU-8 firing at the front armour of a Leman Russ wouldn't even scratch it, whilst an assault cannon supposedly has a chance. I'll try to find a Fluff assault cannon quote, but don't hope too much, I don't tend to buy many BL books, just borrow them.




Armor wise a Leman Russ has 200mm of front armor according to IA:1 which is frankly a much more realistic number then the WD. The IA books are written by tread heads so the less silly stuff like 20" of armor don't get used because well it would make a LR even more impractical then it already is, and I'm talking raw space in the vehicle. To even make it remotely plausible as a real tank you need at least an extra inch per dimension(on the model) and the turret needs to be close to baneblade size. to allow for the gunner/loader/commander. and thats with out an additional foot thick of armor.


"M1A2 tanks uniformly incorporate depleted uranium armor, and all M1A1 tanks in active service have been upgraded to this standard as well, the armor thickness believed to be equivalent to 24 inches (610 mm) of RHA. The strength of the armor is estimated to be about the same as similar western, contemporary main battle tanks such as the Leopard 2. "

RHA (Rolled homogeneous armor) is a theoretical basic type of steel plate used to compare armor. Basically, if you've looked at the modern vs 40k tank threads in the past, it's known that modern tanks have much better armor than a Leman Russ, or even a Land Raider (from the front only)

carl
26-10-2007, 18:49
@Omniassiah & Sekhmet: Good points from both of you, i'll wait a bit before getting back to you though, I'm pretty wound up over somthing else and I don't want you guys catching the flack undeservedly.

@Argastes: if you see this lot, could you at least give me a chance to calm down a bit then put my anwsers up. Should avoid repetition all round, and thus frustration.

ANyway, off to play an hour or two of DoW: DC to cool off:D.

Argastes
26-10-2007, 19:34
"M1A2 tanks uniformly incorporate depleted uranium armor, and all M1A1 tanks in active service have been upgraded to this standard as well, the armor thickness believed to be equivalent to 24 inches (610 mm) of RHA. The strength of the armor is estimated to be about the same as similar western, contemporary main battle tanks such as the Leopard 2. "

RHA (Rolled homogeneous armor) is a theoretical basic type of steel plate used to compare armor. Basically, if you've looked at the modern vs 40k tank threads in the past, it's known that modern tanks have much better armor than a Leman Russ, or even a Land Raider (from the front only)

That assessment of an M1's armor protection in RHA equivalence includes the extremely sharp angle of the glacis plate, which is something like 83 degrees--nearly horizontal. If a penetrator struck the armor perpendicularly, it would actually have much less than 24" RHA equivalent to go through. In fact, it would be less than a third of that. Since a Russ' frontal armor is not very well angled, we can safely say that it does NOT rely on armor geometry to increase it's protective qualities. A Russ's frontal armor is probably four to six inches thick from side to side, with MAYBE a 25% increase in effective thickness due to it's slight angling.

@Carl: Yeah, I'll wait for you to make another post. No sense in this turning ugly.

Sekhmet
26-10-2007, 20:02
That assessment of an M1's armor protection in RHA equivalence includes the extremely sharp angle of the glacis plate, which is something like 83 degrees--nearly horizontal. If a penetrator struck the armor perpendicularly, it would actually have much less than 24" RHA equivalent to go through. In fact, it would be less than a third of that. Since a Russ' frontal armor is not very well angled, we can safely say that it does NOT rely on armor geometry to increase it's protective qualities. A Russ's frontal armor is probably four to six inches thick from side to side, with MAYBE a 25% increase in effective thickness due to it's slight angling.


Actually, reactive armor is extremely inefficient at sharp angles, so I'm not sure if that's taken into account or not.

And note the word "thickness", not overall protection factor.

Argastes
26-10-2007, 20:13
Actually, reactive armor is extremely inefficient at sharp angles, so I'm not sure if that's taken into account or not.

Not sure what you mean by this, since the M1 doesn't use reactive armor and I didn't mention it.


And note the word "thickness", not overall protection factor.

I guarantee you that when an M1's frontal armor is said to be equal to 24" RHA, that means against a projectile on a horizontal flight path, not one striking the armor perpendicularly. If an M1's frontal armor equated to 24" of RHA when struck perpendicularly, it would equate to at least 100" of RHA(!) when struck by a horizontally flying projectile. Trust me, I know what "thickness" means in regard to tank armor. On modern tanks, it's typically given as an effective thickness against horizontally impacting projectiles, not the "actual" thickness as measured perpendicularly to the armor element's face.

carl
26-10-2007, 23:08
Cheers on waiting on me Argastes.

First, yes I know BL is a bad source, I tend to pick carefully for that reason, going for stuff that doesn’t totally contradict existing core fluff or which makes sense. The source for bolters is the William King SW novels. Their a good source for several reasons, first is that he dosen't tread on the toes of any existing fluff. The second is that within the contexts of a semi-fantasy universe his books pretty much always make sense. Finally GW has with a number of his works turned them more or less official, (Gotrek and Felix for fantasy are the biggest examples), so they can be more or less treated as full cannon in the same ay as codex's and rulebooks unless specified otherwise.

Your quite right on the silliness of some things, but that doesn’t mean that’s not how they work. GW have stated X and we pretty much have to run with it. For example with bolt rounds what their really trying to say is it's some kind of micro fusion warhead, we know that but they got their terminology totally ga-ga.

As to Implosion warheads, the theirs a nice PDF on the net that’s extra material for that new munitorium book, it identifies the Leman Russ AT warhead as a shaped charge. SO implosion warheads are probably really fancily named shaped charge warheads. Have a look for a thread on it in rumours if you want the link.

Much the same applies with your LR comments. The cannon is easy to explain away though. Perception. Most tank guns don't really recoil back very far and they return to their rest position pretty quick, add in smoke and flash and it DOES appear to anything but the most careful watching of the weapon as if it's actually mounted solid to the hull. I beloved that myself for a very LONG time. It wasn't till I saw a video on the net of a tank cannon firing from the inside that I realised it actually recoiled.

I'm pretty sure GW made the same mistake, (that and they can just claim the commander is out of scale so he's not in the way if they built it to scale).

I also screwed up a littlie on the WD info, was quoting from memory.

The cannon is actually a 120mm smoothbore and the armour matches the IA figures you gave, (sort of, see below), although the armour actually says "45-20 mm" in my copy, and I've probably just remembered the 20 and converted it to inches in my head since 20mm looks silly:P, probably a miss print or something.

On the other hand, I expect we'll see GW upsize it a fair bit sometime soon. Rule of cool means they'll want the LR to outdo a modern MBT.

From a science perspective the LR is a bit silly though stats wise though, (I’ll go into that later as it's a bit off topic and is personal views rather than stated facts)

Getting experts in would be nice, but totally pointless, when GW comes up with something they often revise it at a later date, and often those revisions make it more powerful not less. The LR is a decent example, back when they first came up with the thing I bet the stats of the day made it quite good compared to a RL tank of the time. Since then things have moved on. The stats and model haven't changed much but the fluff consistently gives it abilities far beyond it's actual abilities going on stats.

And yes an explosion needs something to go against, (although I don't know if that applies to shaped charges), but even subsonic AT missiles with shaped charges work fine, a Low velocity cannon would still be able to launch a fast enough shell to eliminate that issue from the equation.

Yes the XM109 is 25mm, but it isn't a 25mm high velocity cannon, which is what you need for a Heavy Bolter equivalent. Your talking 1.5m+ barrels, firing shells at over 1000m/s here in a RL weapon, we can't make that kind of thing man portable really.

I think I covered everything, (including getting egg on my face:p).





Now onto my semi-rant about why the 200mm LR armour doesn’t work.


The Leman Russ front armour if the 200mm figure is to be believed must be made out of something stupidly tough because I DO know a fair bit about laser weapons. And a weapon that can do to buildings, (even concrete ones), what a Lascannon can do would blast through 40 inches of modern tank armour without too much effort, (the rule of thumb, (my own, worked out from the statement "10KW per square inch will swiftly pierce inch thick steel" in one of my reference books), for steels is roughly 40Kj per square inch to penetrate 1"of it, so even 600Kj per square inch down range is going to burn through 15" of material). A multi-megawatt laser hit at the target is needed to shatter large amounts of concrete and similar like Lasscannons do.

The other problem is the Land Raider, that DOES have reasonably strong armour, and we can guess a lot about Admantium's properties from what it's used for. It's known to be immensely strong and very heat resistant, we also can infer from it's use as a penetrate a very high mass, so where dealing with a material here that is probably well in excess the ability of modern steel/uranium composites. Add in that I think we can very reliably put it at over 200mm thick and I think we've got obvious issues with the Land raider being much better armoured than the Leman Russ to the point where AV14 front armour on both makes no sense, even beyond GW’s strange rules.

The basic problem with the whole 200mm statement is that we KNOW what destructive effects various 40K weapon have on various non-tank and tank targets.

FW likes to go, "we have X weapon so based on RL it should have X effect, which means X tank has X stats", when we KNOW from fluff sources that the effect is considerably better than modern weapons of an equivalent nature, they also show total ignorance of laser weaponry. That’s why rapid fire lasguns don't work, a 600RPM lasgun with the damage per shot of a modern bullet would be able to burn through over 100mm of armour itself at range, get close enough and hold it steady enough, (or use a hot shot pack to get 10 shots of power in 1 round), and it could go through 200mm no problem...

In other words a powerful rapid fire las weapon like a Multi-laser should burn through a LR's front armour without even trying....

I’m sure you can think of other examples, (Think what heavy Bolter Kraken Penatrator rounds would do for one thing,)

Omniassiah
27-10-2007, 05:34
200mm of front armor is actually not too bad. Considering that they don't state that its a RHA equivalent that would put it at close to 8" of armor, which is a decent amount of armor. M1 is not much more then that. Now the key thing is the composition of the armor a hybrid armor would be required once Lasers are in use which means something in the theoretical nature of composite high density heat dissipating ceramic armors.. which are well past my knowledge of material sciences.

As for the matched Armor on the Russ and Land Raider I would hazard a guess that although the LR uses a much more advanced armor it uses less of it in a more easily distributed method around the vehicle. Ironically speaking we were talking in my LGS about how it would be great to see a D10 version of 40k where units are a bit more delineated in their values and you can get a better idea of stats. Too many stats are tied up between 3 or 4 for infantry and even 10-14 has to display the wide variety of armor values you would see on a battlefield. As such the game stats are even a poor representation of game systems because Maybe the Russ might even have tougher front armor the a land Raider, but as we know has a poor armor distribution that would be found on a line tank.

Its all academic unless I can get my gyrojets bolt rounds to stabilize instead of spinning the bolt round out of control and half the time back into the firer.

And generally speaking anything with a Velocity of over 800m/s is classed as High velocity. Even the mighty GAU-8 shares a similar MV to the M107 or XM109. Though the enlarged 30mm round(its not even close to a standard 30mm) has enough additional mass combined with the DU penetrator core gives it armor punch far in excess of a normal 30mm.

Argastes
27-10-2007, 15:17
Alright... carl, with regard to the HB vs. autocannon question, I'm going to respond to your earlier post that dealt with that issue, because I already had a lengthy response typed up for it, and didn't see your request to wait until I was just about to post it, so I saved it. I deleted the part about LR armor since that issue seems to have already been covered. Hopefully this will settle the issue fairly conclusively:


On Heavy Bolters, have you or Argastes actually read the fluff for blot weapons, nothing in that remotely indicates subsonic performance in the slightest.

The velocities I suggested as representative of a heavy bolter were well in excess of the speed of sound, which is about 340 m/s at sea level; I suggested 600-800 m/s for a heavy bolter shell. That's supersonic by a wide margin.


What the fluff is very clear on, (especially for the smaller Bolter), is that’s it's quite capable of punching clean through modern armoured vest equivalents before exploding and we know from both their explosive effects on people and their ability to blow fist sized holes out of Power Armour, (i.e. fist size holes in steel/ceramic composites), that they clearly have explosives, (and thus probably rocket propellants), that are vastly more powerful than anything we use today. Theirs nothing I can find that indicates a heavy bolter is not equivalent to a 30mm modern cannon, no matter how impossible it would be for us to make it.

Again, I never said it wouldn't be equivalent to a modern 30mm cannon. I said it would be equivalent to a modern 30mm cannon in the 30x113mm Aden/DEFA class, perhaps with somewhat lower velocity because an HB shell apparently contains less propellant than a 30x113mm shell. I guarantee you that a 30x113mm cannon shell moving at 600-800 m/s would easily account for the described characteristics of a heavy bolter shell—in fact, realistically, it would be much MORE powerful than a heavy bolter shell is supposed to be.


And NO a 25mm high velocity cannon does not convincingly fulfil both roles in any way shape or form, it would be vastly outperformed by a heavy bolter…

Please go back and read over my technical comparison of a 30mm heavy bolter to a 25mm autocannon, which showed that if a heavy bolter was equivalent to a modern-day 30x113mm cannon with slightly lower (but still supersonic) velocity, and an autocannon was equivalent to a 25x137mm cannon such as the M242, then the autocannon would still be twice as powerful despite it’s smaller claiber. No, a 25mm autocannon would not be "vastly outperformed" by a heavy bolter that equated to a 30mm cannon. All 30mm cannons are not more powerful than all 25mm cannons.


…and still wouldn't be man portable because of it's huge MV would need a weapon with a barrel in the same length range as a GAU-8, and as you pointed out that’s totally impractical for man portable purposes.

This is untrue. There have been several high-velocity 25mm-class cannons that were man-portable by a two-man team and were perfectly practical. For example, look up the Swiss Tb.41 of WW2, which was of 24x138mm caliber--nearly identical to the 25x137mm caliber I have suggested as an autocannon equivalent. Not only could it easily be transported by a two-man team, it was light enough to be towed by one man on a bicycle! It massed only 53 kilograms empty, and was semiautomatic using the short-recoil principle of operation. With the addition of a 10- or 12-round drum magazine in place of the Tb.41’s standard box magazine, and a different trigger group to enable short bursts as well as single shots, it would be a perfect match for the autocannon carried by IG heavy weapons teams--and yes, it would be vastly MORE powerful than a heavy bolter, if a heavy bolter is similar to a 30x113mm cannon with less propellant in the cartridges.

As for the claim that it's barrel would be in the same length range as the GAU-8's, that's not true. The Tb.41's barrel was only 151 cm long. A GAU-8's barrel is nearly a meter longer (235 cm IIRC).


Because of what we KNOW about a heavy bolter it just isn't physically possible to come up with a man portable high velocity cannon that’s more powerful, it's that simple.

No. I'm sorry, but that's just not true. Not only is it physically possible, it's already been done by the Swiss in WW2, and probably by some other people as well. To repeat: A HB shell that's equivalent to a 30x113mm shell would develop, AT MOST, 75,000 joules of energy, and probably more like 50,000 joules since HB cartridges are clearly shorter, and contain less propellant, than 30x113mm cartridges. Whereas an autocannon shell that's equivalent to a 25x137mm shell would develop 130,000 joules of energy with the right ammunition. And the real-life example of the Swiss Tb.41 proves that a lightweight, man-portable automatic weapon in such a caliber is perfectly possible.


If you want proof, look at the models again, they may be in heroic scale, but the shell size compared to the cartridge size is huge, and they should be in scale to each other, do the same for a GAU-8 or a modern 20mm cannon, the cartridge is tiny by comparison, (you could explain it away with higher energy propellants, but that really doesn’t make sense, the recoil on any large weapon would be unmanageable with it).

Not sure what you're talking about here, I don't own any IG autocannon teams so I rely on online pics.... if you could link me to a pic that clearly shows what you're talking about, that would help.


If you want a readily accessible artwork example of how big an Autocannon is, open the Apoc book and look at the very first drawing, (the page with the words APOCALYPSE on it with a Baneblade underneath), look at the Baneblade’s Autocannon, then compare it to the big gun, (and then do the same with the model to prove it isn't heroic scale). Considering we KNOW the LR battlecannon is 200mm and that the BB cannon is more powerful, (and thus probably larger), are you really telling me that gun is a 25mm weapon?

But look at the heavy bolters on the Baneblade’s bow turret in that same picture. They are clearly of MUCH larger caliber than the coaxial autocannon; if that coaxial autocannon is 57mm, then those heavy bolters are at least 120mm! You ask whether I can seriously claim that the autocannon in that pic is 25mm; I ask whether you can seriously claim that those heavy bolters are 30mm. That picture is actually an argument AGAINST your claim that autocannons would have to be larger in caliber than heavy bolters, since it shows the HBs as much larger in caliber. Clearly the weapon muzzles in that picture are not drawn to any realistic scale.


Which is where the real issue hits us. You CAN'T come up with a weapon that’s high velocity, packs the supposed destructive punch of an Autocannon and is still man portable AND a useful main weapon for a Leman Russ and Predator AND a Co-Axial for a Baneblade with an 8"+ main gun.

Yes, you can. A high-velocity 25mm weapon fits all those criteria. A lightweight variant with a small magazine would be man-portable, which is demonstrated by the real-life example of the Swiss Tb.41. A vehicular variant with a larger feed system, such as an externally-driven linkless conveyor system, would be a useful main weapon for the Predator, because plenty of real-life medium AFVs (which is what the Predator is; a medium fire support vehicle based on an APC hull) have mounted high-velocity 25mm cannons and can use them to good effect. A twin 25mm cannon armament, as on the Exterminator, has also been used on real-life AFVs of quite large size, typically for anti-aircraft use but also effective against ground targets. And a single 25mm cannon would be a quite reasonable coaxial armament for a superheavy tank. Bear in mind that even the largest modern MBTs, such as the M1A2, mount only a 7.62mm machine gun as their coaxial armament--a weapon that delivers about 3600 joules of energy per round, as compared to the 130,000 joules delivered by each round from a high-velocity 25mm autocannon. I don't see why it's unreasonable for a superheavy tank's coaxial armament to be a weapon that's normally used as a MAIN armament on modern-day vehicles.


That would let us cut the calibre of the man portable version somewhat although we are limited partially by the need to remain better than the Heavy Bolter, (otherwise why would both exist in the same regiments). Still we could drop it down to a 40mm medium velocity cannon, sort of a cross breed between a high velocity cannon and a high velocity grenade launcher.

At the same time a larger calibre weapon for the Predator / Exterminator / BB which could easily be equal or in excess of 57mm.

But I’ve already explained, and demonstrated with real-world examples, that a weapon can be smaller in caliber than another weapon and yet be much more powerful. An autocannon is not limited to large calibers just because it’s better than a heavy bolter; it could easily be smaller in caliber than the HB and still be a better weapon. And it's not necessary to dream up multiple different weapons to represent autocannons: A 25mm HV cannon could be man-portable in one configuration, a satisfactory vehicle armament in another, and substantially more powerful than a 30mm heavy bolter in both.


And yes I do have an idea of the size of a normal 57mm weapon, I’m a bit of an avid geek on military tech myself, I believe it was the Russian L-60 57mm AAA gun you gave the pics of. It's in one of my books, (Artillery of the World). My point is a weapon doesn’t necessarily have to be that big, an AAA cannon uses a very long barrel and powerful powder charge to get the round high enough to hit the target.

I accounted for these things, and assumed that a 57mm weapon in an infantry mount would use a much shorter barrel and lighter mechanism as you described, and I still concluded that it would be too massive and heavy to square with what we know about the IG infantry autocannon. Even if you could completely remove the barrel, and reduce the amount of material used in the action by, say, 50% (which is a huge reduction), you'd still have a weapon that weighs several hundred pounds, which is much too heavy for a weapon that can be moved by a two-man team. To get a weapon that could be moved about by a two-man team, you'd have to reduce the weight of a real-life 57mm cannon by AT LEAST a factor of ten. Shortening the barrel, and using low-pressure ammunition to reduce the thickness of the chamber walls, simply cannot provide such a massive reduction in weight, unless you went so far that you turned the "autocannon" into an overgrown version of the M129; which is not at all how it's described.


An Autocannon doesn’t need that kind of length, (if you want proof, look at the Hydra, it uses faster firing, longer barrelled Autocannon for it's AAA weapons indicative IMHO that conventional Autocannon are well below the lengths, fire rates, and thus velocities of modern AAA weapons of the same calibre).

I'm not comparing the conventional autocannon to a dedicated 25mm anti-aircraft cannon (which would be something like the Oerlikon KBB/KBD series), I'm comparing it to a Tb.41 (in the infantry variant) or M242 (in the vehicle variant). So although 40K autocannons might well be shorter-barreled than modern purpose-built AA guns of similar caliber, that doesn't mean they would be also shorter-barreled than modern general-purpose cannons of similar caliber. There are 25mm cannons which are purpose-built for anti-aircraft use, such as the KBB I mentioned above, and they do develop higher velocities than the 25x137mm weapons I'm proposing as an autocannon equivalent; so they could be considered modern-day analogs to a Hydra's guns.

Also, if anything, the Hydra's armament is an argument against 40K autocannons being large in caliber. Let's examine the Hydra: A vehicle based on a Chimera IFV hull (M2 Bradley equivalent, so in the 25-30 ton range), armed with four long-barreled, high-velocity autocannons in an air-defense turret. If these autocannons were anything close to modern 57mm guns, an IFV hull could never be fitted with four of them. Even ADA vehicles built on MBT hulls in the 40 to 50 ton range--which probably have twice the load capacity of a Chimera hull--only carry two weapons when armed with 57mm guns (examples: ZSU-57, Chinese Type 80). Four 57mm guns would be just too heavy and massive. Even when you scale down the weapons to "only" 35mm, two guns is still the upper end of the practical armament for tank-based ADA vehicles (such as the Gepard, Japan’s AW-X, Contraves ATAK, Marconi Marksman system, etc.). So an ADA vehicle based on a Chimera hull, which is significantly lighter than the tank hulls used in the above examples, would probably only be able to mount a single 57mm gun. MAYBE two if you really pushed turret size and weight to the absolute limit; but never four. If a 50-ton MBT chassis can only mount two of those things, why would you think that a 25-ton IFV chassis could mount four?

On the other hand: A quad 25mm mount is a perfectly reasonable armament for an ADA vehicle based on the hull of an IFV in the 25-30 ton range. There are several real-world examples of IFV-based air defense vehicles using quad 25mm cannons, such as the OTO Melara SIDAM 25. Four 25mm cannon are definitely not too massive and heavy to fit into a turret that will go on an IFV hull; four 57mm cannons would be.


EDIT: Oh yeah, regarding anti-laser armor, the substance that actually has the highest heat of vaporisation per unit of mass is plain old carbon; so if a vehicle was going to be fitted with armor designed primarily to protect against lasers, it would probably want to use a substantial thickness of graphite tiles or something similar.

Also, regarding the question of how easily 40K laser weapons would burn through steel armor, remember that this assumes the beam could be held on the exact same spot of armor for several seconds--which is questionable on a battlefield. Remember also that the instant a laser starts to burn into material, the beam starts to become degraded just above the target point by vaporized material outgassing from the target point; if you were burning through 8" of steel very rapidly, then by the time the beam had burned halfway through, it would be trying to shoot down a 4" deep hole with incandescent gases escaping from it at high speed. That would severely degrade the beam's effectiveness.

Sekhmet
27-10-2007, 15:46
EDIT: Oh yeah, regarding anti-laser armor, the substance that actually has the highest heat of vaporisation per unit of mass is plain old carbon; so if a vehicle was going to be fitted with armor designed primarily to protect against lasers, it would probably want to use a substantial thickness of graphite tiles or something similar.


Or boron carbide or diamond.

Argastes
27-10-2007, 15:53
Or boron carbide or diamond.

Yeah, diamond would work as well. I doubt boron carbide would be as good against lasers; just because a material contains carbon doesn't mean it has similar physical properties to pure carbon, although I don't know what boron carbide's heat of vaporisation is, so I couldn't say for sure. However, if a tank's armor was designed to protect against conventional threats as well as lasers, then yes, a boron carbide ceramic would probably be a good choice.

EDIT: On an only vaguely related note, I've always thought that the Space Marines could have the best (non-superheavy) tank in the game if they used a reconfigured Land Raider hull as the basis of a dedicated MBT. Here's how it would look: You take a Land Raider hull and get rid of the silly troop compartment, which is what gives it such a ridiculously high profile (the crew compartment is stacked on top of the troop compartment; it's like the design is deliberately configured to make it's profile as high as possible!). This would enable it to be much lower to the ground, probably no higher than half the height of a normal Land Raider. You give it a solid, severely angled glacis instead of the ridiculous front end it currently has--I dunno how it gets a frontal AV of 14 when half it's frontal aspect is taken up by a hatch/ramp contraption which is apparently only a few inches thick, and the other half is poorly angled (the section behind the heavy bolters turret isn't angled at all!). You get rid of the sponson-mounted lascannons; side sponsons are one of the worst possible ways to mount a vehicle's main armament, and have been obselete since WW1 in real-life tank design. Besides, lascannons are far from the best main armament possible. You don't see modern tanks armed with four 40mm guns when they could pack a single 120mm gun.

This brings us to the subject of the main armament. This would be mounted in a turret atop the hull, situated far back towards the rear of the vehicle (remember, the engine is in the forward hull now). In other words, a turret/engine configuration similar to that of the Israeli Merkava. The turret would also be LARGE, unlike the comically undersized turrets on most 40K tanks; like a modern MBT, this thing's turret would be as wide as the vehicle's body, and at least as long as it is wide. The armor on the turret face, like the armor on the glacis, would be sharply angled from the vertical; the armor on the sides of the turret would be angled as much as possible, although not too sharply or the turret's interior volume starts to get impractically small. I see several possibilities for the main gun itself. One would be a large, high-powered laser weapon much more powerful than a lascannon; maybe something like the Leman Russ Destroyer's armament, although I don't have the pertinent IA book so I'm not sure how powerful that thing is. We could maybe go bigger. If a Land Raider's electrical power supply can satisfy the power demands of four lascannons, it can just as well meet the power demands of a single mega-lascannon that's four times as powerful. In a similar vein, it might mount a powerful plasma weapon, less powerful than a plasma blastgun but more powerful than a Leman Russ Executioner's main gun. Or, in the realm of projectile weapons, it could be fitted with a Baneblade cannon or some similar type of plus-sized battle cannon (ideally with APFSDS ammunition available). OR (moving completely outside the realm of "standard" Imperial weapons now), it might be fitted with a powerful electromagnetic gun, either a railgun or a solenoid coilgun. Yeah, I know the Imperium isn't "supposed to" be able to make them, but any techmarine with half a brain ought to be able to figure it; they're very simple weapons in principle, and again, if a Land Raider can supply sufficient electrical power to keep four lascannons firing, it can just as well provide sufficient electrical power to operate a very powerful electromagnetic gun firing small kinetic penetrators at hypersonic speeds. Although this armament wouldn't have as much general usefulness as a powerful laser/plasma cannon or a large-caliber conventional cannon, and would be sort of limited to a specific anti-tank role, so maybe the others would be better. At the other end of the spectrum, a vulcan mega-bolter would be a plausible armament as well, especially against well-armored infantry like Chaos Space Marines.

Coaxial armament would probably be either a heavy bolter or an assault cannon, maybe an autocannon (several real-world tanks use automatic cannons as coaxial armaments). The commander's cupola would mount a heavy bolter or assault cannon. There'd probably be three crewmen in the turret, so each of the other two hatches would mount a storm bolter on a pintle (following the Israeli example of mounting several machine-guns on their tank's turrets). If the main gun was a conventional cannon and didn't use an autoloader, the turret crew would be a commander, a gunner, and a loader. Otherwise, the third crewman in the turret would be a sensor/commo operator, and would probably also serve as a third set of eyes just to increase general awareness--and since 40K infantry can often pack a lot of powerful close-range anti-tank weapons, it would be even more essential to watch out for infantry with AT weapons than it is in real armored warfare. I might also like to add a weapons mount on the forward part of the hull, probably with a heavy bolter or another assault cannon, although it would be much more intelligently designed than the normal LR's twin heavy bolter mount, which compromises the frontal armor and has a bad fire arc. I'd want something more like the bow machine gun mounts of real tanks from the WW2 period, or a remotely-operate barbette mount like those on the Russian BMPT "Terminator". It should also be possible to mount a "pod" of several hunter-killer missile launch tubes on either side of the turret; theoretically, other "podded" armaments could also be attached to the mountings used to fit the HK missile launchers, so the tank's firepower could be augmented by adding gun pods with additional heavy bolters/assault cannons, or rocket pods loaded with unguided rockets carrying various types of warheads. There could be rocket pods holding a few large rockets (each one similar in size to an HK missile, but unguided and shorter-ranged with a larger warhead that wouldn't necessarily be an anti-tank type), and pods containing numerous smaller rockets like the 70mm FFAR pods used on modern US attack helicopters. A flamethrower pod, containing a heavy flamer and a fuel supply, would be useful in urban combat.

Wow, I guess I typed up a lot about this thing. Well, I think it would be useful for the Marines. Their tank arsenal is a little inadequate; they have the Predator, which is a lightish/medium tank, and the Land Raider, which is quite large but tries to fulfill the roles of both heavy APC and main battle tank, with the result that it's passable as both but excels as neither. However you use it, you're wasting half it's capabilities, or at least not exercising them to their full potential, and it's armament is certainly impressive but could be a lot better for a vehicle that's supposed to be a heavy tank. It's also poorly designed (very high profile, sponson-mounted main guns, etc.).

carl
27-10-2007, 17:53
Ahh, your last paragraph in the big reply cleared up a few things nicely in some respects.

Basically we've been using completely different designations of high velocity cannon" you've probably been using some official standard whereas Iíve had to stick to what I can come up with as I don't know the official standard.

For me I was classing anything below a 30mm AAA cannon is a medium or low velocity weapon, (for a 30mm calibre gun). Which was also the weapon type I was comparing the heavy bolter to.

That explains some of the confusion away.

Before I move on I want to go back to the heavy bolter.

Are you really telling me a 30mm cannon such as what you described is that powerful?

Because the way it's described in the fluff, (a short bursts seems to be able to shred a marine and his armour in the SW novels), it's quite capable of blasting through several inches of Steel/Ceramic composite armour, (over a rather large area, like most of the chest plate), and pulping the guy inside who's as tough without his armour as a normal human with an armoured vest (or other similar armouring), and thatís pretty much with every shot, a marine just takes a lot of hits to go down because he's so Uber L33t, (GW and their idiocy :rolleyes:).

TBH I believe that's beyond anything but the GUA-8 in the 30mm calibre, but I often underestimate real destructive potentials so I was willing to let a 30mmm AAA gun do that in RL. If your weapon can do that feel free to fill me in:).

As to the hydra, it looks like I must be underestimating the weight of a 57mm AAA gun built using modern construction techniques. Specifically my book, (I can' find it ATM, must be in my storage boxes, so this lot is coming from memory), puts the single 20mm Orliken mounts at around 1000KG's, and various twin mounts using various different cannon at the 1500-2000kg level. The various 57mm where around the 5 ton mark for single mounts total, (I think, somewhere between 4 and 7 tons though for most largish calibre AAA guns). So I put the guns themselves at about 2 tons.

Thus a quad mount would be 8 tons plus mounting, or about 15 tons plus ammunition carried. Add that to me putting the chimera at much more than 20-30 tons, (I'd got the chimera as about 40-50 tons, the LR as 100tons+ and the BB near the 1000ton mark). and a quad 57mm looked pretty possible for the Hydra.

On that note Iíd got the short barrelled low velocity cannon I suggested tagged at about 150KG's, drag-able on a trailer and lift-able by two people for short time periods. If you want the reasoning for that figure let me know.

To come back to the man portable 25mm cannon. What you suggest is certainly reasonable sounding to me, (if you'd explained what type you meant by high velocity earlier Iíd have agreed it was probably possible, although Iíd have been a bit more sceptical than ATM I admit), I just doubt it's ability to match a heavy bolter, but Iíll let you handle that one.

Your quite right on the laser stuff you mention, but supposedly it's only plasasteel and ceramics, (we'll assume plasteel is just a fancy name for an advanced material similar to modern steels for simplicities sake), The ceramic will help a bit, but heat then too quick and their prone to shattering. Yes vapour can get in the way, but Lascannons are seemingly pulse weapons with a pulse length of somwhere around 0.25 seconds. It won't eliminate it, but you dump a dozen megawatts in 0.25 seconds into a lump of metal and your going to explosively vaporise a lot of material and burn through feet of the stuff. A Lasguns firing rapidly would actually be an even better penetrator because the pulsing nature would allow the vaporised metal to dissipate, thatís why laser pulsing was developed.


As to the Land Raider stuff you mentioned.

First the Lascannons may be a bit sllily mounted, but the sponsons don't seem to be very integral to the rest of the tank. Apart from power and coolant feds theirs nothing puncturing the tanks armour, so it's not like it hurts the tanks armour scheme that badly, although the weapon are easy to knock off.

Also it uses Lascannons instead of something bigger because something bigger just isn't needed normally. Fluff wise twin Lascannons REALLY chew enemy tanks apart without too much trouble. So by mounting 2 mounts they get twice the firepower, it's like going for 2 single 5" guns on a navel ship over 1 single twin mount because against patrol boats the two single mounts are just as deadly and let you shoot 2 targets at once.

As to the thin ramp. My question is so what? Look at the armour material. It's used in very effective penetrator rounds so it's clearly very dense, probably equal or superior to depleted uranium and is far stronger than steel even when heated to a couple of thousand degrees, (i.e. it's still insanely strong when inside a shut down plasma reactor). Something like that is going to be at least 2 times a s good as the best modern tank armours. So even though it's only a few inches think. I'd say where still looking at front armour in spite of all the shot traps and thinish nature thatís as good as an M1A2 if what was said earlier by Omniassiah is true.

Cheers to Omniassiah for pointing out the probable thickness of real tank armour, I always thought modern tanks had at least 15Ē real inches, and had heard a quote putting the physical thickness of an M1A2 at over 20Ē, looks like someone got the RHS and actual thickness mixed up. Really should have spotted that earlier myself hough:(.

Argastes
27-10-2007, 22:03
Yeah, 30mm cannons that are "only" in the 30x113mm range, rather than the 30x173mm range, really are that powerful; the Apache's chin gun (M230) is perfectly capable of destroying a tank despite being much weaker than the GAU-8. A number of Iraqi T-72s have met their fate at the hands of Apache's M230s, both in the 1991 war and the 2003 invasion. If BL books really make out heavy bolters to be as powerful as you describe, then I don't know if I'd say that a 30x113mm cannon is actually "much more powerful"; maybe just "as powerful". I never thought of a heavy bolter as an effective anti-tank weapon, and I always imagined the thickness of a Marine's breastplate as more like an one to two inches, rather than 'several inches'. But that's BL for you, I guess. Anyhow, yes, a 30x113mm cannon can quite readily destroy a tank. It would probably have some trouble with the latest-generation MBTs, but a T-72 or equivalent is lunch for that thing.

Anyhow, I'm glad to learn our disagreement stemmed from different understandings of terminology; it's always nice when things like that clear up.

Regarding 57mm mountings: I'm not sure about those figures you've given. I would estimate a quad 57mm mounting at much heavier. Let me explain the basis for my estimation: The British Vickers 2-pdr. AA gun of WW2 was a 40mm weapon, and a quad mounting for this thing weighed around 10 tons in the power-operated Marks. Each Vickers 2-pdr. was about 290 cm long, weighed 356 kg, and developed around 220,000 joules of muzzle energy per shot with AP shells. On the other hand, a high-velocity 57mm gun, such as what the Hydra would be armed with if it's guns were 57mm, would be at least twice as long (high-velocity 57mm guns tend to be 550-650 cm in length), twice as heavy (700-800 kg apiece), and develop four to six times the muzzle energy (about 800,000 to 1.3 million joules per shot) and thus four to six times the recoil. I find it hard to believe that a mount accommodating four such guns would weigh less than 20 tons. A Marconi Marksman turret, which is a twin-gun 35mm mount rather than a quad-gun 57mm, weighs 11 tons (and is rather light for a twin 35mm turret, because it lacks an autoloader and some other features). Anyhow, even if your estimate of 15 tons is accepted, and even if a Chimera really did weigh 40-50 tons instead of 25-30 (which I think is doubtful; does anyone have the IA book which gives it's weight?), a 15-ton turret (more like 17-18 with ammo) is pushing the limits on a 40 or 50 ton vehicle that wasn't designed from the ground up to have a heavy turret. There's a reason all the modern twin-gun 35mm and 57mm AA vehicles are built on MBT hulls, and for obvious reasons, their turrets usually weigh several tons less than even your rather low estimation of a quad 57mm turret's weight.

Regarding the low-velocity 57mm cannon you suggest: If it weighed 150 kg it would be a passable light field artillery piece, that could be towed by a light vehicle, but I don't agree that it would be man-portable by a two-man team even for short distances. If the gun itself is 150 kg, the shield and carriage/mount are going to come to at least another 30-50 kg, plus ammunition, which would be at least a kilogram per round even if you used a short, stubby projectile and a very small propellant charge. So the men would have to move around a weapon system that, with a useful ammo load, would weigh more than 200 kg, probably close to 250. I suppose it might be possible for them to lift it and lug it a very short distance, but a weapon served by a two man crew needs to be more portable than that. They have to be able to change position by a few hundred meters with reasonable speed, and that's just not possible with a 200+ kg weapon--they'd be stopping every twenty feet to catch their breath, and they'd probably put their backs out! Heavy machine guns and light automatic cannon, considered the heaviest weapons for which only a two-man crew is necessary, typically mass well under 100 kg with mounting, tripod/carriage, and a useful ammo load.

Regarding laser weapons: A laser that pulses at a 240-hertz frequency (which is what a pulse every 0.25 seconds comes to) is not going to be able to put even two pulses on the same target point at battlefield ranges unless the target is stationary and the firing platform is very stable (i.e., not a moving vehicle, or a Space Marine firing one from the shoulder). Also, I don't think that even a multi-megawatt laser could rapidly burn through tank armor; existing multi-megawatt lasers are considered suitable only for defense against aircraft and missiles, which have a skin of thin aluminum--typically less than 5mm thick, as opposed to at least 100mm of steel for tank armor. Pulsing the laser wouldn't help much; it would certainly help with the problem of the beam being degraded by vaporized target material, but it wouldn't change the fact that the beam would have to hold on a single point for an unrealistically long period of time to penetrate the armor.

I suppose you're right about the Land Raider's frontal armor; since it allegedly incorporates an adamantium layer, who knows how tough it really is. But my point is, no matter how tough it already is, it could be made MUCH tougher by properly angling it and getting rid of the HB mount, ramp hinges, and all the other junk that compromises it's integrity. If it's already twice as good as modern tank armor, it could be made FIVE TIMES as good instead. And since the Land Raider is apparently still not invulnerable to anti-tank weapons despite having armor that's twice as good as modern MBT armor, this would be a valuable increase in protection.

My concern over the sponson mounts is vulnerability (which I notice you did mention) and limited fields of fire, not that they compromise the side armor. In addition to having a main armament which is poorly protected against enemy fire, I'd imagine the sponsons would be severely damaged--if not destroyed--the first time a Land Raider had to ram through a concrete wall of any appreciable thickness. And while lascannons may indeed be effective against most tanks in the fluff, the Leman Russ Vanquisher, Destroyer Tank Hunter, Rapier Laser Destroyer, etc. wouldn't exist if the lascannon was the final word in anti-tank weapons. In 40K, there does seem to be a legitimate role for anti-tank weapons that are even more powerful than the lascannon. A lascannon isn't guaranteed to destroy an enemy tank with every shot; a proper battle tank's main gun should come as close to this ideal as possible.

azimaith
27-10-2007, 22:42
I suppose you're right about the Land Raider's frontal armor; since it allegedly incorporates an adamantium layer, who knows how tough it really is.

According to IA2, 200x stronger than conventional steel. And yes they say *conventional*.

Argastes
27-10-2007, 23:09
According to IA2, 200x stronger than conventional steel. And yes they say *conventional*.

Hmmm... for that figure to be meaningful, we'd have to know what they mean by "conventional" steel. Do they mean RHA, which is basically 4340 steel? Do they mean plain old mild carbon steel? There's no such thing as "conventional" steel; even within the range of common steels that they might be talking about, there is a very large variation in strengths. We'd also have to know what kind of strength they're talking about when they say "200 times stronger". Shear strength? Tensile strength? Compressive strength? Many steels have radically different values in these three strengths. And how was the steel manufactured? What quality is it of? Mild steel of average quality might have a tensile strength of 50,000 newtons per square centimeter; the exact same steel alloy, if manufactured to very high standards of quality, could have a tensile strength of nearly 400,000 newtons per square centimeter. In fact, there can be variations by factors of more than 100 even within the range of existing steels. Maraging steel can have strengths in excess of two million newtons per square centimeter, whereas some stainless steels can have strengths as low as 15,000--this isn't that far from Maraging steel being 200 times stronger.

Sorry, I guess I'm being a tech geek. But "200 times stronger than conventional steel" is completely meaningless. And assuming "conventional steel" means normal carbon steel, it's not actually THAT impressive; I mean, yeah, it's still extraordinarily strong, but it's probably not so strong that a couple inches of it (which is what seems to be used in a Land Raider's armor) would offer twice the protection of an M1A2's frontal armor.

azimaith
27-10-2007, 23:50
When they say conventional steel i'd say they probably mean conventionally used steel. RHA isn't really conventionally used(as in multipurpose), and they don't say: "Conventional steel armor."

I remember debating this before with someone else, the LR is rather pathetic compared to MBTs in statistics.

I think its important to note that alot of anti-tank firepower in 40k is laser based, so I'd assume that their heat absorbing properties would be more important to them than their kinetic resistance. Beyond that its also important to understand the imperium has no development cycle, they mostly only replicate. So what they use for "conventional steel" is what STC's they've found to mix it with carbon. Its very much in keeping with the dark ages that this happens. In medieval times when steel was worked by smiths, they merely noted that when iron was worked with certain materials in a forge it came out stronger, thus alot of mysticism grew around it, they had no idea that carbon was the culprit.

In the same way, those who make steel in the imperium simply go by whats written down, not why it works, for that is the purview of the great omnissiah and his machine spirits.

carl
28-10-2007, 00:07
Cheers for that explanation on 30mm cannon, I didn't think they could do that kind of thing, I was aware of the Apache cannon, but thought the cannon was just a slightly downsized weapon in the same class as the GAU-8 rather than something similar to what you where talking about.

As to power armour, 28mm rule of cool again. if you look at the 54mm models wearing it, a normal ][, (who's probably a good heavy weight by normal human standards anyway), ends up roughly doubling in visible bulk, so several inches isn't unlikely, especially when it's supposed to be as thick as the front armour of a rhino.

Pretty much all fluff sources have normal bolters blowing fist sized holes in the stuff, thatís an inch+ right their. William King has Heavy Bolters basically blasting clean through the armour and doing enough damage to force the SM to retire from fighting and a good burst will put them down, (although if they get med aid fast enough they can still survive, thatís SM l33tness for you). No really detailed descriptions of the effects of a single round exist though as Ragnar isn't using a heavy bolter in any of the books I read so it's always someone else at a distance shooting someone near Ragnar rather than right in the thick of it stuff. SO you sort of have to extrapolate from the known detail effects of a bolter and the known general effects of a heavy bolter to get detailed heavy bolter stuff.

p.s. Might want to add that the supposed HB power is only for delay action fused HE, not proper AP ammo, (APBC is un-producible in the IoM for the LR battlecannon supposedly :wtf:, hence why they use hollow charges, allthough they use good ones, (a 120mm LR battlecannon SC can penetrate 180-240mm of armour, so even a 57mm style one would punch through 90-120mm, academic but thought you might want the tech specs from 40K).


Cheers on the 57mm estimation, I was sort of going off the way a 20mm twin mounting only got heavier by about 2/3 again as much as the single mount. So i figured with a 5ish ton single mount, a twin would be about 8 tons, and just made a quick guesstimate from their. I hadn't realised the actual mountings had to be so strong, I always though most of a towed mounts weight was in the carriage and traversing gear, rather than the actual physical mount for the gun, (ignoring the guns own weight in that last statement).

My Chimera weight estimation is was based of the idea it would be a significant proportion of the weight of a LR. The LR is probably erroneous though, I based it off the 20" armour figure rather than the 200mm figure and I always thought modern MBT's where in that weight class too, I hadn't realised they where so light, (comparatively speaking of course).


When I said 150kg's i was meaning including carriage, (probably something simple like what a lot of mortars have, but on a smaller scale, (like this (http://www.israeli-weapons.com/weapons/artillery/mortars/soltam_120mm_m-65/Mortar_120mm_M-65.html) carriage)), so Iíd imagined it as something where the two guys could just grab the towing ring and pull it along on the wheels, lifting it over anything too awkward to pull it over. I always imagined the rest of the squad carrying the ammo distributed around.

Which was really the other reason I liked the Autocannon as a 57mm style weapon. Standered 57mm weapons don't fire that fast and a low pressure one, even with light internals would probably be slower still. An Autocannon/heavy bolter doesnít seem to top 180ish RPM, which seems low for a 25mm cannon, (the HB gets away with it because it has a really low power firing charge, hence slow mechanism actuating).

I guess my theoretical cannon was a kind of Cannon/Mortar/Recoilless Rifle cross if that helps your understanding, which I haven't a clue as to the effectives of really, I was just going on 40K's, lots of explosive=powerful weapon style, (even if itís total garbage in RL:p).

Anyway, not arguing with you, just pointing out my reasoning.


As to the Lascannon: when I said a 0.25 second pulse, I meant delivering the whole burst of energy in 0.25 seconds hen recharging for several seconds before firing again. I.E. a dozen mega joules of energy in 0.25 seconds.

Also, i'm not talking about a dozen megawatt laser, Iím talking a dozen megajoules actually hitting the target, depending on various laser properties, firing platform vibration, and atmosphere conditions, (and range), you might only get a 10th the energy on target with one of the modern lasers. A Lascannon is probably spitting 100megajoules plus out the actual barrel at firing time. But only about a dozen actually reach the target, the rest are lost to atmospheric blooming, (the energy being wasted breaking down chemical substances such as ozone in the air, yes laser wreak the ozone layer:D) and heating. AND aluminium is a bit better at not absorbing the heat, (I believe only half as much energy is absorbed by the aluminium), not to mention their shiny reflective nature.

I agree better design could make the Land Raider tougher, just saying it's still damm strong really.

And yes I agree that their is still a good reason for better weapons, just that in the LR's case they see the trade off in kill probabilities for more shots more useful, the marines do tend to like flanking manoeuvres where they can get shots at weaker armour where it really is a near guaranteed kill.

And of course they have limited fields of fire, but again the marines probably want the ability to hit several dispersed targets in a crowded battle rather than hit two in the same place. Doesnít make a lot of sense with our combat doctrine, but then we donít have special forces with custom tanks.


According to IA2, 200x stronger than conventional steel. And yes they say *conventional*.


I'm pretty sure that for armour density matter allmost as much if not more than actual tensile strength.


If you go here (http://www.specialist-games.com/inquisitor/assets/lrb/InqLRBpart2.pdf) and go down a few pages, (page 8) youíll find a pic of ][ Tyrus in power armour, on page 7 is ][ Eisenhorn for comparison. Thatís how bulky power armour really is, 28mm just obeys rule of cool:p.

Argastes
28-10-2007, 00:10
When they say conventional steel i'd say they probably mean conventionally used steel. RHA isn't really conventionally used(as in multipurpose), and they don't say: "Conventional steel armor."

I suppose so, although even within the category of "conventionally used steels", there's a huge amount of variation. Structural steels and the stainless steel used in cheap kitchenware are both "conventional" by that standard, but they're very different. At any rate, assuming they mean normal mild steel, adamantium being 200 times stronger is impressive but actually rather less over-the-top than a lot of other 40K tech.

I remember debating this before with someone else, the LR is rather pathetic compared to MBTs in statistics.


So what they use for "conventional steel" is what STC's they've found to mix it with carbon. Its very much in keeping with the dark ages that this happens. In medieval times when steel was worked by smiths, they merely noted that when iron was worked with certain materials in a forge it came out stronger, thus alot of mysticism grew around it, they had no idea that carbon was the culprit.

In the same way, those who make steel in the imperium simply go by whats written down, not why it works, for that is the purview of the great omnissiah and his machine spirits.

I'm not sure I'd take the whole "superstitious technological dark age" this far. Although a lot of the ADVANCED technology of 40K (plasma weapons, for instance) is not understood by the people who make and use it, it strikes me as ludicrous to say that they don't even know what makes steel stronger than iron. The AdMech does have an extensive research wing, even if they do little development on the basis of that research. And it's not true that the Imperium has NO development cycle; it just moves very slowly. Occasional, if rare, improvements are made as a result of research and innovation, rather than just STC recoveries. I'm sure the tech-priests understand basic stuff like what makes steel what it is.

azimaith
28-10-2007, 00:19
I'm not sure I'd take the whole "superstitious technological dark age" this far. Although a lot of the ADVANCED technology of 40K (plasma weapons, for instance) is not understood by the people who make and use it, it strikes me as ludicrous to say that they don't even know what makes steel stronger than iron.

According to the forge world books, research is more archeology than research. They discover new technology and they forget others, its a state of technological decay.



The AdMech does have an extensive research wing, even if they do little development on the basis of that research. And it's not true that the Imperium has NO development cycle; it just moves very slowly.

Well it does have a development cycle, I should have been more accurate, its just the development cycle is alot of stuff that has nothing to do with development. Its about sanctifying the new development, its religious approval, and considering the response of the divine machine spirit over reseaching whats happening, seeing what will happen should these changes be made, then implementing them efficiently.


Occasional, if rare, improvements are made as a result of research and innovation, rather than just STC recoveries.

According to the FW books they don't reseach(In the modern sense), they uncover. Innovations are to fill in gaps where knowledge is lost rather than to improve capabilities. Vehicles in the imperium don't get more fuel efficient, longer ranges, better hitting power through development. They might be adapted to a particular role, such as the LR conqueror vs the Leman Russ, but you won't see them develop a LR vanquisher from a leman russ (as the vanquisher is an STC design).



I'm sure the tech-priests understand basic stuff like what makes steel what it is.
Steel is a divine manifestation of the machine gods will. They may understand that iron with carbon is steel, but its stronger because the machine god wills it as such. When a vehicle breaks down they try supplications and prayers (along with the appropriate rituals which are of course, repairs) but rather than determining "its unfixable" if it fails to work again its because the machine spirit is unwilling to continue.

Only the highest in the order ot techpriests realy understand whats going on. The others just follow the "recipe" and hope it works. Its much the difference between a person reading instructions online on fixing an engine, and a person whose gone through schooling to understand why and how an engine works.

This is from IA1.

carl
28-10-2007, 00:34
This is from IA1.


Which ignores stuff like the Hellfire round and the Bharan Seige masters kit.

ALl that was independently developed with no STC's involved.

Argastes
28-10-2007, 01:01
Hmm, sounds like FW stuff has retconned a little. Older GW fluff sources, like the 2nd Edition CI, describe the AdMech as engaging in a fair amount of research, and even though new technology that doesn't come from an STC is viewed as unacceptable or whatever, little bits of progress do occur here and there.


Oh yeah, about blended metal rounds... I'm not interested in getting into a big discussion about whether they really work or not, but I can tell you that the spherical, omni-directional "blast" effect is common to gunshot wounds (and wound simulations) of all types, not just those of the blended metal rounds. It's caused by the shock of the bullet entering the target medium; despite the fact that the bullet is only moving in one direction, it's impact creates a shock effect which displaces target material in ALL directions. This creates an effect called the temporary wound cavity or "stretch" cavity, which rapidly closes back up, leaving only the permanent wound cavity or "crush" cavity (which is the area of tissue actually destroyed by physical contact with the bullet and/or bullet fragments). There's no magical "backwards expansion" going on here, just a perfectly well-known and commonplace phenomenon in terminal ballistics. If you look up images of gunshot wound cavity cross-sections, you can see the same sort of "spherical" (actually usually prolate, but whatever) wound cavities from normal, non-blended-metal bullets.

Also, just as a side note... the first video you provided to illustrate the effect is a little ridiculous, and it doesn't prove anything. It looks impressive, but when you actually consider the test it depicts, it's completely meaningless. A pot roast was blown to smithereens by a .300 Winchester Magnum? Wow, shocking! You don't need blended metal bullets to do that; any halfway decent hollowpoint would do exactly the same thing. Actually, the .300 Win Mag is such an incredibly powerful round (typically used for hunting moose, elk, and grizzly bear) that I wouldn't be surprised if even a spire-pointed FMJ round did that to a pot roast, given that a pot roast is such a ludicrously small amount of meat in comparison to that round's power. When you put 3,600 foot-pounds of energy into a chunk of meat the size of a basketball, what do you expect? I've seen much smaller rounds than a .300 Win Mag pulp/liquefy a volume of tissue at least as big as a pot roast, and bigger in some cases, so that video doesn't seem to prove much. As for the second video, Firefox wouldn't play it; says the protocol isn't associated with any program. If you can tell me how to get it to play, I'll watch it. But I'll tell you right now, if all it shows is a bullet creating a spherical cavity in some ballistic clay, that's nothing new; it happens with normal bullets all the time. The only thing "going on" is the creation of a temporary wound cavity by the shock wave of a fast-moving impactor. Also, neither cooked meat nor ballistic clay are even CLOSE to human flesh analogs for the purposes of testing a bullet's terminal performance. So just because a bullet behaves a certain way in a pot roast or a block of clay doesn't mean it will behave even close to that way in a person or a live animal (cooked meat is very different in it's physical properties than living tissue).

And even though I don't want to derail this thread into a debate over whether blended metal rounds work, there are a few things I have to point out. You said that LeMas's reluctance to provide bullets for independent testing is understandable because they are trying to maintain secrecy. But if they provided bullets to a reputable independent ballistics lab, such as H.P. White, they could be perfectly confident in the safety of any confidential information. Labs like H.P. White make their business by providing independent, unbiased, and professionally-conducted tests of firearms, ammunition, etc. for major firearms manufacturers, so that when the manufacturers advertise their product and boast of it's abilities, they can point to the test results from the independent lab, and people will know that they aren't just stuff making up. Lots of manufacturers use these labs to test products that are secret or confidential in some way, and can be perfectly confident that they won't have sensitive info stolen or leaked. These labs are very reputable, and in fact their success as businesses depends on them maintaining reputations for security and confidentiality; if they couldn't claim to be secure and confidential, firearms and ammo manufacturers would stop sending them sensitive new products to be tested. I would understand if LeMas didn't want to have their product evaluated by a gun writer, or a magazine like Guns & Ammo; in those situations, there would be a legitimate concern over security/confidentiality, and over being targeted with a "smear campaign" of misleadingly negative reviews. After all, gun writers and gun magazines are often notoriously biased and unscientific in their testing; a gun writer might flat-out make up negative stuff about a product that he just didn't like. But when they say they won't send it to a reputable, professional ballistics lab, and say that the reason is that they don't want their product to be stolen or leaked, then their claims become much less credible. You can't seriously claim that H.P. White or a similar lab would do that; it's just not realistic. And LeMas knows that. It sounds like an excuse not to have their product scientifically tested, plain and simple.

I also think you misunderstood the Tactical Forums pages you linked me to, and are confused about who Stan Bulmer really is. Stan Bulmer isn't a guy who claimed to have debunked blended metal bullets and was later proven to be a fraud; he's a sale rep for LeMas! He is the one arguing for the effectiveness of blended metal bullets. Although you were correct in saying that his claims have been proven totally false ;). Unfortunately, since he claimed blended metal bullets DO work, that means that the bullets have been exposed as fraud, not "vindicated".

I also read the NAP link you provided, and it's talking about something totally different. Note that the reactive materials it discusses use metal OXIDES, which are combustible (e.g. aluminum oxide in thermite); whereas the blended metal bullets do not. Yes, the NAP link shows that it is possible to create solid projectiles which ignite and explode as they penetrate a target, but the described process is completely different from the alleged mechanism by which blended metal bullets work. It's also worth noting that if blended metal bullets actually exploded due to a chemical reaction, then such bullets in small arms calibers would be illegal for land warfare under the provisions of the St. Petersburg Declaration of 1868, which the US military abides by; yet the US military apparently considered the ammunition (since they rejected it only after testing it thoroughly), which is a pretty solid indication that it does not explode, combust, deflagrate, or anything else of that nature. The military doesn't bother testing equipment they are not willing to use.

And as a final note, I have to point out the incident in which "blended metal bullets" were cut open with a rotary cutting tool and found to be completely normal copper-jacketed LRN bullets with a nylon pellet in the base. This is documented on the Tactical Forums pages you linked to. If these tests were not actually conducted on LeMas' blended metal bullets, and are an attempt to discredit LeMas by claiming to have used them when actually using ordinary bullets so that it looked like LeMas was lying about their bullets... then why does the graphic heading on LeMas' own website about blended-metal bullets contain pictures of bullets which are exactly identical to those revealed to be ordinary LRN bullets when cut open? I don't buy the theory that some guys decided to falsely discredit LeMas by cutting open normal bullets which they claimed were blended metal bullets, and that LeMas simultaneously, just by coincidence, has decided to add pictures of the exact same type of normal bullets to their website for no reason.

Well I guess I talked about blended metal bullets a lot even though I said I wasn't going to. Damn.

azimaith
28-10-2007, 01:27
Hmm, sounds like FW stuff has retconned a little. Older GW fluff sources, like the 2nd Edition CI, describe the AdMech as engaging in a fair amount of research, and even though new technology that doesn't come from an STC is viewed as unacceptable or whatever, little bits of progress do occur here and there.

I should be more specific, the admech doesn't allow it, but individuals within the admech still do it. The orginizations dogma is relatively clear, but that doesn't stop people from doing it anyhow, and if the result is particularly effective and demanded its unlikely there will be negative reprecussions to those developing it, but its not encouraged.



Oh yeah, about blended metal rounds... I'm not interested in getting into a big discussion about whether they really work or not, but I can tell you that the spherical, omni-directional "blast" effect is common to gunshot wounds (and wound simulations) of all types, not just those of the blended metal rounds. It's caused by the shock of the bullet entering the target medium; despite the fact that the bullet is only moving in one direction, it's impact creates a shock effect which displaces target material in ALL directions. This creates an effect called the temporary wound cavity or "stretch" cavity, which rapidly closes back up, leaving only the permanent wound cavity or "crush" cavity (which is the area of tissue actually destroyed by physical contact with the bullet and/or bullet fragments).

This is what got to me. When I saw it the first thing I would assume is that there would be damage inward and an increasing angle basically forming a cone. I suppose it has to do with the way the kinetic material is transfered.



There's no magical "backwards expansion" going on here, just a perfectly well-known and commonplace phenomenon in terminal ballistics. If you look up images of gunshot wound cavity cross-sections, you can see the same sort of "spherical" (actually usually prolate, but whatever) wound cavities from normal, non-blended-metal bullets.

Like I said before, thats what got to me, i'm not a ballistics expert so its easy to construe things at face value. So yes, I was wrong on this and on some other counts. Its good to know the truth however, makes me wiser for this topic should it come up some other time, some other place :).



Also, just as a side note... the first video you provided to illustrate the effect is a little ridiculous, and it doesn't prove anything. It looks impressive, but when you actually consider the test it depicts, it's completely meaningless. A pot roast was blown to smithereens by a .300 Winchester Magnum? Wow, shocking! You don't need blended metal bullets to do that; any halfway decent hollowpoint would do exactly the same thing. Actually, the .300 Win Mag is such an incredibly powerful round (typically used for hunting moose, elk, and grizzly bear) that I wouldn't be surprised if even a spire-pointed FMJ round did that to a pot roast, given that a pot roast is such a ludicrously small amount of meat in comparison to that round's power. When you put 3,600 foot-pounds of energy into a chunk of meat the size of a basketball, what do you expect?

I believe the first video I put out was of a .45 ACP, not a .300 winmag.
Maybe i'm mistaken theres about 3 videos at the blackwater shoot out that have different calibers.



I've seen much smaller rounds than a .300 Win Mag pulp/liquefy a volume of tissue at least as big as a pot roast, and bigger in some cases, so that video doesn't seem to prove much. As for the second video, Firefox wouldn't play it; says the protocol isn't associated with any program. If you can tell me how to get it to play, I'll watch it. But I'll tell you right now, if all it shows is a bullet creating a spherical cavity in some ballistic clay, that's nothing new; it happens with normal bullets all the time. The only thing "going on" is the creation of a temporary wound cavity by the shock wave of a fast-moving impactor. Also, neither cooked meat nor ballistic clay are even CLOSE to human flesh analogs for the purposes of testing a bullet's terminal performance. So just because a bullet behaves a certain way in a pot roast or a block of clay doesn't mean it will behave even close to that way in a person or a live animal (cooked meat is very different in it's physical properties than living tissue).

Hmm I got mine to play on RealPlayer. You were using the Blended metal v clay block on the upper right side of the 2005 shoot out right. Its in the grey box.



And even though I don't want to derail this thread into a debate over whether blended metal rounds work,..*snipped*]

Yes it was misread, BMT from LeMas is indeed fraudulent by a US government test of it. Blended Metal rounds however are not fake and are under investigation by the US military.



I also read the NAP link you provided, and it's talking about something totally different. Note that the reactive materials it discusses use metal OXIDES, which are combustible (e.g. aluminum oxide in thermite); whereas the blended metal bullets do not. Yes, the NAP link shows that it is possible to create solid projectiles which ignite and explode as they penetrate a target, but the described process is completely different from the alleged mechanism by which blended metal bullets work.

The initial point is to show that an exploding bullet can be produced.



It's also worth noting that if blended metal bullets actually exploded due to a chemical reaction, then such bullets in small arms calibers would be illegal for land warfare under the provisions of the St. Petersburg Declaration of 1868, which the US military abides by; yet the US military apparently considered the ammunition (since they rejected it only after testing it thoroughly), which is a pretty solid indication that it does not explode, combust, deflagrate, or anything else of that nature. The military doesn't bother testing equipment they are not willing to use.

I'm fairly certain that exploding ammunition is legal for "equipment disposal". Theres alot of things in alot of these delarations that aren't legal but still get used.
Perhaps i'm misinformed again, but I recall a marine friend of mine telling me that .50's were illegal to use on infantrymen because it causes "undue suffering".

Another was that you weren't allowed to us WP on enemy infantry but still allowed it for "marking smoke" (The old, I just *marked* those infantry for aipower that didn't come through.)
He told me, and perhaps this is uncommon, that according to things like .50's and WP, "Situation Dictates".




And as a final note, I have to point out the incident in which "blended metal bullets" were cut open with a rotary cutting tool and found to be completely normal copper-jacketed LRN bullets with a nylon pellet in the base. This is documented on the Tactical Forums pages you linked to. If these tests were not actually conducted on LeMas' blended metal bullets, and are an attempt to discredit LeMas by claiming to have used them when actually using ordinary bullets so that it looked like LeMas was lying about their bullets... then why does the graphic heading on LeMas' own website about blended-metal bullets contain pictures of bullets which are exactly identical to those revealed to be ordinary LRN bullets when cut open? I don't buy the theory that some guys decided to falsely discredit LeMas by cutting open normal bullets which they claimed were blended metal bullets, and that LeMas simultaneously, just by coincidence, has decided to add pictures of the exact same type of normal bullets to their website for no reason.

The issue here is that they have *another* evaluation of the bullets effects by another Dr.Sydney Vail essentially completely disagreeing with the report on the forums. To be honest, I don't trust anyone who would put test results up on a internet forum to discredit someone for all to see. That strikes me as rather unproffesional, and if LeMas refused to let anyone test their bullet it strikes me as suspect that someone would suddenly get a bunch of bullets to test them with. As the government apparently tested BMT (which the results of which I can't be absolutely certain of because the results are in ARTEC) and the same person who did the test apparently claimed it proved them fraudulent. (Which once again, can't be verified without access to ARTEC).



Well I guess I talked about blended metal bullets a lot even though I said I wasn't going to. Damn.
I think what i'd want to say to all of this is:
Exploding small arms bullets are plausbile, if not likely with the development of non-explosive solids to form RM as well as through more conventional fuzing mechanisms and in the future, were likely to see exploding ammunition (technically or practically) that meet up with bolter like standards.

And of course, there will be frauds along the way, but we'll get there eventually, if we aren't there already.


Which ignores stuff like the Hellfire round and the Bharan Seige masters kit.

ALl that was independently developed with no STC's involved.

I'm talking about the general admech dogma, just because thats what they say doesn't mean thats what everyone does much in the same way come catholics will use birth control yet still call themselves catholic. It would just be considered heresy if it were discovered and sufficient political power could be gathered behind those throwing the blame, which would be difficult considering the relative effectiveness of the material.

Its better to think of the Admech like the inquisition, they will have their own individual factions which will believe different thinks, and just as a puritan inquisitor can't necessarily get a carta extermis to pass on a radical just by submitting it, a admech puritan couldn't declare heresy on a more radical Admech just by saying it.

Argastes
28-10-2007, 01:44
As to power armour, 28mm rule of cool again. if you look at the 54mm models wearing it, a normal ][, (who's probably a good heavy weight by normal human standards anyway), ends up roughly doubling in visible bulk, so several inches isn't unlikely, especially when it's supposed to be as thick as the front armour of a rhino.

Well, unfortunately, "several inches" of ceramic armor is approaching what modern tanks have, and is much thicker than a Rhino's frontal armor probably is, if a Rhino is anything like a modern lightly-armored APC. Marines' power armor is supposed to offer considerably less protection than dedicated tank armor, even if it is much tougher than "normal" personal armor like carapace armor, so I think an inch, or two at the most, is reasonable. I always assumed that much of the thickness of power armor was accounted for by the musculature elements under the armor plating, so who knows. This is all 100% speculative, so I can't say my ideas are more valid than yours.


Pretty much all fluff sources have normal bolters blowing fist sized holes in the stuff, that’s an inch+ right their.

But since a bolter shell is .75 caliber and uses an armor-piercing explosive projectile fused to detonate inside the target.... they should make holes three-quarters of an inch in diameter, not fist-sized. To me, this makes it sound like these fluff sources are dramatically overestimating the destructive effect of a boltgun shell. When it comes to boltguns, we don't have to turn to fluff sources like BL to provide us with a description of their effects, because GW's own core fluff provides us with quite detailed info. We know the exact caliber and projectile length of a boltgun projectile, and know exactly what type of payload it carries, and even have cross-sectional diagrams that can be used to estimate, for example, the dimensions of the armor-piercing component, and the size of the explosive core. We can extrapolate a boltgun shell's performance from this data, rather than relying on exaggerated fluff descriptions.


William King has Heavy Bolters basically blasting clean through the armour and doing enough damage to force the SM to retire from fighting and a good burst will put them down, (although if they get med aid fast enough they can still survive, that’s SM l33tness for you).

Now this would indicate that a heavy bolter is less effective than a 30x113mm cannon; a "good burst" from an M230 would blow a Marine's armor open like a tin can, and turn him into meaty chunks.

It sounds like the issue here is that BL fluff, including King's work, has no consistency in describing weapon effects. A boltgun shell would be much less destructive than they describe (although still very deadly), whereas if a heavy bolter really is 30mm, it should be not only capable of killing a Marine with only one shot, it should be an effective anti-tank weapon as well.


When I said 150kg's i was meaning including carriage, (probably something simple like what a lot of mortars have, but on a smaller scale, (like this (http://www.israeli-weapons.com/weapons/artillery/mortars/soltam_120mm_m-65/Mortar_120mm_M-65.html) carriage)), so I’d imagined it as something where the two guys could just grab the towing ring and pull it along on the wheels, lifting it over anything too awkward to pull it over. I always imagined the rest of the squad carrying the ammo distributed around.

That's a good point about the squad carrying the ammo, I'd sort of forgotten about that. However, unfortunately, the IG autocannon has no wheels; it's tripod-mounted like a machine-gun. This is one of the things that suggests to me a lighter weapon than 150 kg, even if that weight included the carriage. Even if the carriage was included in the 150 kg, that's still unreasonably heavy for a weapon served by a two-man crew.


Which was really the other reason I liked the Autocannon as a 57mm style weapon. Standered 57mm weapons don't fire that fast and a low pressure one, even with light internals would probably be slower still. An Autocannon/heavy bolter doesn’t seem to top 180ish RPM, which seems low for a 25mm cannon, (the HB gets away with it because it has a really low power firing charge, hence slow mechanism actuating).

I guess my theoretical cannon was a kind of Cannon/Mortar/Recoilless Rifle cross if that helps your understanding, which I haven't a clue as to the effectives of really, I was just going on 40K's, lots of explosive=powerful weapon style, (even if it’s total garbage in RL:p).

Anyway, not arguing with you, just pointing out my reasoning.

I do appreciate it. I don't disagree that a large AGL/small auto-mortar, or whatever you want to call it, would be an effective weapon; but I think it would be a bit too large to be a tripod-mounted infantry weapon, and would have to be either vehicle-mounted or used as a light artillery piece that is towed behind a vehicle and served by a crew of three or four men (just like the 120mm mortar in your link, in fact). Plus such a weapon wouldn't square with the appearance and described effects of a 40K autocannon, which the 2nd Edition wargear book explicitly describes as a "high-velocity" automatic cannon. And the models have a long, slender barrel by 40K standards even if it is a bit stubby in realistic scale.

BTW, it's possible to build automatic weapons that fire at high cyclic rates even with very low-pressure ammunition; if the moving parts in the action are lightweight proportional to the energy supplied by the ammunition, it can fire quickly no matter how weak the ammunition's powder charge. Plus, if a weapon is externally driven (which HBs may well be), it can fire as fast as you drive it no matter what ammo is used.


As to the Lascannon: when I said a 0.25 second pulse, I meant delivering the whole burst of energy in 0.25 seconds hen recharging for several seconds before firing again. I.E. a dozen mega joules of energy in 0.25 seconds.

Also, i'm not talking about a dozen megawatt laser, I’m talking a dozen megajoules actually hitting the target, depending on various laser properties, firing platform vibration, and atmosphere conditions, (and range), you might only get a 10th the energy on target with one of the modern lasers. A Lascannon is probably spitting 100megajoules plus out the actual barrel at firing time. But only about a dozen actually reach the target, the rest are lost to atmospheric blooming, (the energy being wasted breaking down chemical substances such as ozone in the air, yes laser wreak the ozone layer:D) and heating. AND aluminium is a bit better at not absorbing the heat, (I believe only half as much energy is absorbed by the aluminium), not to mention their shiny reflective nature.

I see what you mean about the laser; I still don't agree that a laser weapon could ever be a viable anti-tank weapon without such a huge power supply that it would be orders of magnitude more efficient to simply use a missile or kinetic shell, but that's a discussion for another thread. This thread seems to already have several discussions going on in it. I should point out that it's not true that reflective materials are better protection against lasers; reflectivity offers little protection. Even if a surface is 99% reflective (which is much better than most mirrors, let alone an aircraft or missile skin), the 1% of energy that's not reflected will be, with any laser powerful enough to serve as a weapon, more than enough to almost instantly heat the material to the point that the reflectivity is ruined and the beam's full energy can become incident. Basically, reflectivity at the target point is lost as soon as the laser hits, because the laser changes the physical properties that make a material reflective in the first place.

As for the Land Raider, I do see the rationale for multiple weapons rather than a single more powerful one, although I'd suggest that since a Land Raider only has a two-man crew, the potential for engaging multiple targets is practically nil (and the Machine Spirit doesn't seem to be a very good shot). It would need a gunner for each sponson if it was to really make good use of those multiple weapons to engage multiple targets simultaneously on a crowded battlefield.

legio mortis
28-10-2007, 05:24
I should be more specific, the admech doesn't allow it, but individuals within the admech still do it. The orginizations dogma is relatively clear, but that doesn't stop people from doing it anyhow, and if the result is particularly effective and demanded its unlikely there will be negative reprecussions to those developing it, but its not encouraged.
The thing is, you can't group the AdMech into one unified group. As you've also stated, there are different factions with different views on technology and development. Take Stygies VIII as an example. They have entire wings devoted to reverse engineering xenos technology and weapons. They are obviously pretty radical, but you get my drift.

About non-STC innovation, it does indeed happen. A good example would be the Vanquisher cannon. The plans for the original were lost after Tigirus was lost, but Gryphonne Iv and Stygies VIII both created their own versions, and more Forge Worlds are attempting to do the same. Additionally, the Tech Adepts of Urdesh created their own original vehicles and technology, completely without the use of an STC.

Now all this is on a galactic scale. Private companies and jointly held AdMech and civilian factories can afford to do much more in terms of innovation and creation in the much smaller planetary and even sector scales.

Argastes
28-10-2007, 07:33
This is what got to me. When I saw it the first thing I would assume is that there would be damage inward and an increasing angle basically forming a cone. I suppose it has to do with the way the kinetic material is transfered.


Like I said before, thats what got to me, i'm not a ballistics expert so its easy to construe things at face value. So yes, I was wrong on this and on some other counts. Its good to know the truth however, makes me wiser for this topic should it come up some other time, some other place :).

Glad I could help explain the issue. And you're right about shape of the cavity when it comes to the permanent wound cavity; it is typically long and tunnel-like, sometimes getting wider as you go inward. It's only the temporary wound cavity, or stretch cavity, that is round or football-shaped. I think part of the misunderstanding probably arises from the ways in which ballistic gel or clay differs from human flesh. In clay especially, the spherical "bubble" that's blown into the clay by the initial shock of the bullet's entry--what would be the temporary wound cavity in human flesh--never closes up, because clay isn't elastic like human flesh. When you shoot a person, the temporary wound cavity quickly closes up as the compressed tissue returns to it's original shape, and only the permanent wound cavity is left. But in clay, and gelatin to some degree, the "stretch" cavity is permanent, and this can be misleading when you see rounds tested in this way. Basically, it makes it look like the round will inflict a permanent wound cavity of the same size as the cavity it makes in the clay/gel, but in reality, that cavity is going to be temporary in a human body.


I believe the first video I put out was of a .45 ACP, not a .300 winmag.
Maybe i'm mistaken theres about 3 videos at the blackwater shoot out that have different calibers.

I'm talking about the first of the two videos you posted to illustrate the "spherical" wounds you were asking about. According to the video tag, it's a .300 WM round striking a pot roast (though it looked more like a ham to me).

I still couldn't get the other video to play :(.


Yes it was misread, BMT from LeMas is indeed fraudulent by a US government test of it. Blended Metal rounds however are not fake and are under investigation by the US military.

Oh yeah, blended-metal frangibles are definitely not fake; in fact, I have one sitting on my shelf in .38 Special. At the gun show that's held regularly in my area, a company that manufactures them always has a booth and hands out individual bullets as freebies. Their appeal is for police officers, prison guards, etc., to whom a round that won't overpenetrate or ricochet is attractive. So in case I ever need to shoot anyone with my .38 and don't want the bullet to be matched to my gun's rifling... I can ;).

But blended-metal frangibles with the described effect of the LeMas round (penetrating armor and then disintegrating in flesh because they're made of "heat-sensitive smart materials") are a joke, and the blended-metal frangibles being tested by the military are conventional frangibles which would have very poor performance against armor plate because they'd disintegrate on impact. They are being investigated for use in urban combat and around noncombatants, where they are attractive for the same reason police and prison guards find them attractive: No overpenetration, and no ricochets. I believe earlier in this thread, Omnissiah mentioned that his unit in Iraq used some, where they performed pretty much as expected--poor penetration, but good terminal effects in flesh.


The initial point is to show that an exploding bullet can be produced.

I never disagreed with that; I was just pointing out that despite their claims to the contrary, LeMas hasn't done that.


I'm fairly certain that exploding ammunition is legal for "equipment disposal". Theres alot of things in alot of these delarations that aren't legal but still get used.
Perhaps i'm misinformed again, but I recall a marine friend of mine telling me that .50's were illegal to use on infantrymen because it causes "undue suffering".

Here's the exact breakdown of what SPD-1868 says: Any explosive or incendiary bullet massing less than 400 grams is not legal for use against infantry in land warfare. Since "equipment disposal" is not use against infantry, it's perfectly legal to use explosive or incendiary ammunition in that capacity.

On the issue of .50 caliber weapons being illegal to use against infantry, yes, you are misinformed and so is your Marine friend, through no fault on either of your behalves. I'm not particularly surprised, because this is a myth that is so widely believed within the US military itself that lots of soldiers are told by their instructors, during basic training, that they cannot fire a .50 caliber weapon at enemy infantry. This is probably where your friend picked it up; his superior officers told him an outright falsehood!

A .50-caliber weapon, assuming it is not loaded with explosive or incendiary bullets (or hollowpoints or other expanding bullets, lol), is perfectly legal for use against infantry. For US forces, there is no legal injunction against weapons that cause "undue suffering". As long as it's not designed to explode, expand, or burn, it's kosher (and even the ban on explosive/incendiary ammo is followed because we choose to, not because we have to--we never signed SPD-1868, and even if we had, we would only be bound by it's provisions when fighting declared wars against other signatories, i.e. Russia and a handful of European nations).


Another was that you weren't allowed to us WP on enemy infantry but still allowed it for "marking smoke" (The old, I just *marked* those infantry for aipower that didn't come through.)
He told me, and perhaps this is uncommon, that according to things like .50's and WP, "Situation Dictates".

WP is actually kind of a grey area. On one hand, it's an incendiary weapon, so it is theoretically legal to use it against enemy infantry if it is delivered in a shell massing more than 400 grams. On the other hand, it also produces poisonous gas (all that white smoke is toxic if inhaled), and thus could be considered a chemical weapon, which would be prohibited under Declaration II of the Hague Convention of 1899 (which prohibits the use of "projectiles, the object of which is the diffusion of asphyxiating or deleterious gases"). The question comes down to whether the diffusion of poisonous gas is the "object" of WP shells, or just a side-effect of their intended object. I'd say it's a side-effect, since the rounds are clearly "intended" to be used for target marking and incendiary purposes.

Of course, in practical terms, your friend is right--situation dictates. Troops in combat will use whatever arms are available if those arms would offer an advantage, and treaty be damned. No group of soldiers is going to increase the risk to their lives, which is what they would do by deliberately putting themselves at a disadvantage by refusing the use a potentially effective weapon, just to satisfy the requirements of a 100-year-old treaty on the "laws of war". The only real law of war is, "Win."


The issue here is that they have *another* evaluation of the bullets effects by another Dr.Sydney Vail essentially completely disagreeing with the report on the forums. To be honest, I don't trust anyone who would put test results up on a internet forum to discredit someone for all to see. That strikes me as rather unproffesional, and if LeMas refused to let anyone test their bullet it strikes me as suspect that someone would suddenly get a bunch of bullets to test them with. As the government apparently tested BMT (which the results of which I can't be absolutely certain of because the results are in ARTEC) and the same person who did the test apparently claimed it proved them fraudulent. (Which once again, can't be verified without access to ARTEC).

I've read Dr. Vail's report and it unfortunately I would not characterize it as a credible endorsement of LeMas blended metal bullets. His report is composed of nothing but his description of what he saw as an observer in a "live fire demonstration" (not a test) that was apparently conducted by unidentified persons. We have no idea who conducted the demonstration he describes; did LeMas conduct it? Was it conducted by a police force evaluating the ammunition? By the military? By a gun writer reviewing the product? Information about this "live fire demonstration" is conspicuously absent. Furthermore, the performance of the blended metal bullets was evaluated in comparison to "conventional duty" ammunition. Well, what the hell does that mean? In the case of the 5.56mm test, it was made clear that they used the M855 and some round called the "M-262" (I guess meant the Mk.262), but what about with the pistol test? FMJs? Hollowpoints? Conventional duty ammunition for a police officer and conventional duty ammunition for a soldier are two completely different kinds of ammunition, and even within broad categories like "jacketed hollow point," there is a HUGE range of variation in performance; some JHPs are well-designed and function fabulously, whereas others are total crap that fail to expand. For the pistol comparisons, what was the make and model of this "conventional duty" ammunition? And in all tests, what weapons were? If the 5.56mm ammunition they used was fired from the wrong type of rifle, it would not perform properly, because such ammunition's terminal performance is highly sensitive to variations in rifling twist rate and barrel length. If they fired certain types of "conventional duty" JHP ammunition from a handgun with too short a barrel, it would not have the velocity to expand properly--there are different types of JHPs designed to work at different velocities. Failing to provide this basic info, which any responsible evaluator would be sure to provide, is a major strike against the scientific rigor and objectivity of these tests. It also makes the results of the test meaningless to us, because all we know is that the LeMas bullet did more damage than a completely unknown bullet fired from a completely unknown weapon. That tells us nothing. Are we expected to just *assume* that the mystery bullet was a premium-quality high-performance hollowpoint, and then be impressed with the LeMas bullet's superior performance? How do we know it wasn't a military FMJ round, or an obsolete design of hollowpoint, in which case the LeMas bullet's superior performance is completely unremarkable, and could just as easily be obtained with any modern off-the-shelf hollowpoint of decent quality? The comparison in his report tells us nothing. Imagine what you would think if an automobile manufacturer claimed that their latest model of car was, "Found in tests to be much faster than a normal car!", and provided no further information. Wouldn't you want to know what "normal car" they had used as a baseline for comparison? Do they consider a "normal car" to be a Ford Focus, or a BMW 3-series? That makes a large difference, don't you think?

Furthermore, the terminal performance of these bullets is not quantified in any meaningful or rigorous way. There is no measurement of wound cavity length or diameter, no measurement of wound track lengths, only some gory pictures with subjective, unquantified descriptions. Many of his descriptions are of questionable scientific value. For example, he says that the LeMas bullets caused "a quicker end to the brain's ability to maintain coordinated function". Well, how was this determined? Did they actually implant electrodes in the brains of the hogs and have them hooked up to brain activity monitors as they were being shot, to determine which round resulted in a faster cessation of brainwave activity? (That is a technique that has actually been used in live-target tests of a bullet's terminal performance, by the way.) Or did they simply observe which hog twitched and gasped for a longer time period after being shot? And he says the LeMas bullet has a higher potential for hemorrhage--how was this determined? Unless they had a study group of dozens or hundreds of hogs, and could promise us that each one was shot in an exactly identical fashion, this statement is indefensible. You can't draw meaningful scientific conclusions from a sample group of one or two subjects. So it might be alright if he had just said, "The hog shot with the LeMas bullet displayed more hemorrhaging than the hog shot with the conventional bullet", but that's not what he said. On the basis of one or two hogs' wounds, he categorically declared that the LeMas bullet will cause more hemorrhaging than other bullets. Not a valid claim; the sample group is too small.

So we don't know what ammunition was used as a comparison to the LeMas handgun bullets, and we don't know how much more severe the LeMas bullet's wound effects really were. And even in the 5.56mm test, where we do know the exact bullets used for comparison, the comparison is of questionable fairness; both bullets used were military FMJ rounds, which are prohibited by the Hague Conventions from being designed to expand, and must rely on tumbling and fragmenting at the cannelure for their wounding effects; a fairer comparison might have used a modern, well-designed hollow point bullet. Designing a round that will inflict more severe wounds than a military FMJ round is not exactly revolutionary. About the only worthwhile thing in Dr. Vail's report is his point that ballistic gelatin is not necessarily an accurate analog for human flesh, which is a good point.

Bottom line, Dr. Vail's report is unscientific and uninformative. It draws overly broad conclusions from an unacceptably small and imprecisely gathered volume of test data, and leaves out a large amount of information that is absolutely vital to determining the validity of these tests--information that ought to be expected as standard in reports of this type. Since he doesn't tell us who conducted the test, or where we can find a record of the test results for ourselves, we can't verify anything about the fairness or scientific rigor of the test or it's methodology. We don't know whether the test was overseen or monitored by any independent observers with the purpose of ensuring objectivity and consistency. In other words, this comparison fails to meet every standard of scientific credibility that should be met when testing firearms technology (or anything else). We have no way of even knowing that this test wasn't conducted by LeMas themselves, deliberately using poorly-performing bullets as a comparison to make their own product look good. All we know is that Dr. Vail went to an undisclosed location and watched a test be conducted by unidentified persons under unknown auspices (if any), comparing the blended metal bullet to some other bullets of an unidentified type fired from unidentified weapons at unspecified ranges, and that he saw the LeMas bullets make bigger holes. Big whoop, proves nothing.


I think what i'd want to say to all of this is:
Exploding small arms bullets are plausbile, if not likely with the development of non-explosive solids to form RM as well as through more conventional fuzing mechanisms and in the future, were likely to see exploding ammunition (technically or practically) that meet up with bolter like standards.

And of course, there will be frauds along the way, but we'll get there eventually, if we aren't there already.

I certainly agree with this. I have definitely never said that explosive small arms ammunition is some sort of technical impossibility with current technology; just the opposite. In fact, several types of real-life explosive ammunition, such the Raufoss Mk.211 APHEI round (for .50-caliber weapons) and the FRAG-12 explosive shotgun shell, prove that explosive rounds in the same size range as a bolter shell definitely ARE possible--after all, they exist! And solid bullets made of reactive materials, which explode despite containing no explosive composition or fuses, are also certainly a possibility. What I'm saying is that although such bullets may be possible, the LeMas blended metal round is not such a bullet, even if it did work as claimed (because it doesn't explode due to a chemical reaction, it just disintegrates like any other frangible bullet); and that it's highly doubtful whether it even works as claimed.

azimaith
28-10-2007, 08:27
The more I understand of this the more i'm wondering what is with LeMas. Certainly they could fool some people, but I figure it would become obvious very quickly as they sold bullets that they didn't work as intended.

Regardless, i'm certain we will see actual functioning bullets within a short period. I do have to thank you for setting me straight, i'd rather be wrong and corrected than "right" and deluded.

Not much more to say on the topic for me I suppose unless people come out with more questions on imperial tank statistics from the IA books.

Argastes
28-10-2007, 13:58
The more I understand of this the more i'm wondering what is with LeMas. Certainly they could fool some people, but I figure it would become obvious very quickly as they sold bullets that they didn't work as intended.

Regardless, i'm certain we will see actual functioning bullets within a short period. I do have to thank you for setting me straight, i'd rather be wrong and corrected than "right" and deluded.

Not much more to say on the topic for me I suppose unless people come out with more questions on imperial tank statistics from the IA books.

Well, I think part of the answer is that LeMas is NOT selling many bullets; they don't seem to be having any commercial success. Based on their website and what I've seen, they're a pretty small operation which isn't doing much business. It's probably only a couple of guys. They don't seem to have any customers. The firearms world has lots of little fringe companies like this; small outfits trying to sell a "revolutionary" product that's really nothing special, which manage to stick around for several years despite having little to no success. I would guess that LeMas Ltd. will fade away in the next couple years. The same is true of RBCD, the company that manufactures the stuff; I mean, look how professional THEIR website (http://www.rbcd.net/) is :rolleyes:. Again, probably a small outfit with very little commercial success, since they apparently can't even afford to hire a decent web design guy. Since the blended metal bullets don't seem to have been adopted by any police forces, or the military, they're probably not being used by anyone who would notice that they don't work as intended (civilian shooters, especially the kind who would buy dubious "super-ammo" from a no-name company like LeMas, are probably not going notice that performance isn't as advertised, since it's not like they're going to be shooting a lot of people with it, or even testing it properly).

Anyhow, I'm glad I was able to help explain this issue; sorry if I seemed to be harping on it, I just get frustrated by companies like LeMas and their baseless, over-the-top claims. Speaking of providing info from IA, if you could provide us with some weight figures for the Chimera and Leman Russ, that'd be very helpful; now I'm curious about them.

azimaith
28-10-2007, 20:11
A Ryza pattern leman russ (which is appears to be standard) weighs in at 60 tonnes. 7.08 meters long, 4.86 neters wide, and 4.38 meters tall. Its got .45meters of ground clearance and a max 35KPH speed on road, a max 21KPH off road.

Different leman russ tanks have a slightly different weight based on their varients (demolishers ect)

A Gryphone IV varient chimera (about standard)
Weights 38 tonnes, is 6.9 meters long, 5.7 meters wide, an d 3.72 meters tall. Its max on road speed is 70kph and its max off road speed is 55kph

Argastes
28-10-2007, 23:24
Thanks, that helps. Looks like carl was closer to a Chimera's weight than I was after all.

I like how their IFVs are capable of drastically outpacing their tanks, meaning that a Chimera's speed is totally wasted when fighting alongside Russes....

azimaith
28-10-2007, 23:37
Yep, well I suppose the imperial doctrine was never about mobile warfare (for most cases). I'd assume alot of the chimeras role is to take troops from one part of the miles long battle lines to another point and fight when it got there.

legio mortis
29-10-2007, 00:57
Yep, well I suppose the imperial doctrine was never about mobile warfare (for most cases). I'd assume alot of the chimeras role is to take troops from one part of the miles long battle lines to another point and fight when it got there.
Actually, staying mobile is the way of war that the IG prefer. To quote the Munitorum Manual and the 2nd ed. IG codex:


The Chimera can transport its infantry squad for many miles and this mobility is essential to the fast moving warfare that typifies an Imperial Guard
attack

and


The Imperial Guard is a highly mechanised fighting force whose strength derives from huge reserves of artillery, tanks, mobile weaponry and men.

Argastes
29-10-2007, 02:05
The Imperial Guard is a highly mechanised fighting force whose strength derives from huge reserves of artillery, tanks, mobile weaponry and men.

And yet everything has to move at the cripplingly slow speed of a Leman Russ or risk outrunning their armor support on the advance.... oh, 40K :angel:

Omniassiah
29-10-2007, 02:28
Funny thing about that Argastes It happens in the US Air Cav now with the Chinook(sp?) it has a max air speed about 20mph faster then any of the gunships if I remember correctly.

azimaith
29-10-2007, 02:31
I don't think transport helicopters are used in the same manner as APC and Tank combination in mobile warfare doctrine. And of course theres also the issue is that the gunships don't travel at 21KPH vs 60KPH.

Argastes
29-10-2007, 02:34
Funny thing about that Argastes It happens in the US Air Cav now with the Chinook(sp?) it has a max air speed about 20mph faster then any of the gunships if I remember correctly.

I had no idea, that's quite strange. Maybe the Chinook (correct spelling, BTW) fleet recently got new engines? But anyhow, as azimaith points out, that's a much smaller gap, relative to the top speeds of helicopters, than the gap between Chimera and Russ. And the gunship/slick relationship is a little different from the tank/APC relationship... aren't attack helicopters typically used in an independent capacity?

EDIT: Oh yeah, plus... Blackhawks are the main troop carriers in US air assault forces, not Chinooks. IIRC, Chinooks are generally held in separate companies.

azimaith
29-10-2007, 02:43
I believe you often see alot of attack helicopters is CAS missions as well as escort.

As for the Blackhawks vs chinooks, I think thats right, Chinooks I believe were developed more for their heavy lift (granted they can fit alot of people in them) which of course could explain why they have a higher top speed, a more powerful engine.

Anyhow, the big difference is (from what I understand) is that when you send in troops with mobile warfare the tanks and infantry operate together, if you were to simply send the transport helicopters and the gunships together you'd end up with very little staying power compared to MBTs.

So mobile warfare is tanks and APCs moving together in support of one another, while transport Helo's I believe do more shuttling after you've taken areas, deep insertions and extractions.

Argastes
29-10-2007, 02:47
Good point about escort, but I think the US Army doesn't like to use attack helicopters for CAS nowadays, due to their poor loiter time, heightened vulnerability to ground fire, limited armament, and so forth. CAS typically gets left to the Air Force, I think.