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Quadros
07-02-2010, 15:06
So I'm one of those geeks who likes to complain about largely irrelevant plot holes, you lucky people. I've enjoyed Gaunt's Ghosts for years, and I have been impressed with the way Abnett has been able to maintain great consistency through the number of books he has. I mean sure, he slipped up in mentioning Merrt as a sniper after he'd been shot, and the whole Kolea/Dalin relationship is really inconsistent and confusing, but all in all, a decent enough job.

My favourite character by far is Larkin. I love the portrayal of sniping in the books, and it's a subject I have great personal interest in. (My great grandfather was a British Sniper in WWII, and I play a LOT of Modern Warfare :P.) All in all his depictions of sniping are incredibly gripping and are accurate to the conditions of modern sniping. All was good.

Then, a couple of weeks ago, I was re-reading Sabbat Martyr (while drinking some tea) and a sudden and horrifying realisation hit me. Larkin uses a longlas. Not a conventional gun. Tea went EVERYWHERE. It was horrible.

See, my understanding of physics is rudimentary at best ('a' in science at GCSE five years ago, check me out!) but as far as I can tell, a long las shot is still a laser, and thus still light. A thread on the matter on lasguns in general seems to back me up on this. And thus the problems begin. Because a laser is light. Light doesn't have mass. And therefore it's not going to be effected by wind, or gravity. even the target's movement will have a negligible effect, As long as the cross-hairs are on the target when you fire, at any manageable range the impact will be pretty much instantaneous. (I'm assuming here that lasers still travel at the speed of light, since that's what they are and stuff.)

Most frustrating for me is the passage where that blood pact sniper hears a las shot, thinks he's shot the saint, but then nessa's round hits him. Yeah, very dramatic Abnett, but light travels faster than sound. He's going to be hit way before he hears the shot.

I mean I get that there's not much to work with when technology turns a potentially dramatic and impressive skill and talent of war into basically point and click shooting, but it's not like he was bound by fluff, is it? The generic sniper rifle in 40K fires highly advanced poison darts, doesn't it? Or just give him a solid slug weapon, there are enough of them about, aren't there? It's not like solid ammo weapons are defunct in the 41st millennium, is it?

So yeah, that's my (actually stupidly long, reading back over it) geeky rant. You may have missed a birthday reading it and for that I apologise.

snottlebocket
07-02-2010, 15:18
There's really not much point in applying logic to 40k's lasweapons, they behave nothing like our lasers or light for that matter.

The main advantage of las weaponry in 40k seems to have nothing to do with all the advantages of high powered lasers but more with the fact that apparantly for them it's the easiest to produce and maintain technology. (probably a long story about the templates and whatnot, what it comes down to, lasweaponry is easy to massproduce)

The dart rifles you mention are still described to use las technology. The necromunda armoury describes them to shoot a highpowered very narrow laserbeam first to punch a hole through any armour before firing the dart.

Most of the slug weaponry mentioned in 40k seems to be of the low quality, high volume of fire, low accuracy kind of stuff. Weapons that are easy to hit with only because they throw out clouds of buckshot or hails of slugs. Kinda like the cheap crappy AK's they mass produce in third world countries.

Iuris
07-02-2010, 15:23
Well, while I'd like lasers to behave like lasers as much as the next nerd, I'd point out that different technologies may mean different things.

A laser may not cause a sonic boom, but the mechanism producing it may itself produce sound and/or recoil (chemicals needed to create the reaction needing to be injected into reaction chambers and so on, focusing crystals, coolants flushing and so on). With GW never having provided any details, maybe they do create noise and recoil.

Also, all sniper rifles (except the silent russian specials) will essentially hit at the same time the bullet hits the target - the bullet is supersonic and creates a sonic boom in its wake. It'll be there before the other sounds made by the rifle arrive :)

snottlebocket
07-02-2010, 15:28
Well, while I'd like lasers to behave like lasers as much as the next nerd, I'd point out that different technologies may mean different things.


If the laserbeam is hot enough to superheat the air around it, it will most definitely create a boom. It's exactly the same effect that makes lightning boom.

Air superheats and moves outward, then collapses back in again. If they're hot enough to instantly burn holes in folks (or even tanks) I imagine they make quite a bang.

Quadros
07-02-2010, 15:32
I know about the whole 'narrow laser punch' thing with the needle rifles, but any knowledge of sniping or basic physics tells you that when you have two projectiles, one with mass and one without, fired under identical conditions, variables are going to affect the mass projectile and not the laser and they'll never hit exactly the same place. I kind of liked the idea that the dart was programmed to fire the needle laser just before impact, since that makes sense, and the incredibly prohibitive cost of such a bullet would make it usable only by snipers, basically.

And Boltguns, the chosen weapon of the Astartes, are probably not 'low quality, low accuracy'. They're status symbols, they've got to be good, right?

And yeah, I know that logic is not really important in sci/fi and fantasy, but you know that annoying guy you hate watching films with because he points out obscure omissions that just ruin the movie if you think about them enough? Yeah, I'm that guy. The guy who was shouting 'JUST TAKE THE EAGLES FRODO!'

N0-1_H3r3
07-02-2010, 15:40
'JUST TAKE THE EAGLES FRODO!'
And your logic-senses didn't pick up on the fact that there were eagles with a 20m wingspan in the first place?

More importantly, you try convincing massive birds of prey to go anywhere near to what is essentially the manifest spirit of immortal evil in jewellery form. I imagine that, had Gandalf suggested such a course of action to one of the Eagles, the immediate response would not have been a kind or pleasant one.

Lord_Crull
07-02-2010, 15:45
As long as the cross-hairs are on the target when you fire, at any manageable range the impact will be pretty much instantaneous. (I'm assuming here that lasers still travel at the speed of light, since that's what they are and stuff.)


We have at least one example of Dark Eldar dodging las-bolts in the fluff before. So does that mean Dark Eldar are FTL?

snottlebocket
07-02-2010, 15:48
And Boltguns, the chosen weapon of the Astartes, are probably not 'low quality, low accuracy'. They're status symbols, they've got to be good, right?


Boltguns are pretty great, the imperium is full of great weapons that can't be massproduced or at least not massproduced in the kind of numbers needed to equip the guard.

Considering what the basic boltgun fires, I'm actually wondering if it's even practical to equip guard with them. Space marines are some big guys that train daily, giving guns that shoot fist sized explosive bolts at machinegun rates to regular joes is probably not going to end well. Guard tend to work in teams with additional training just to fire guns that space marines shoot from the hip.

The guard are such a massive organisation that weapon quality isn't nearly as important as the abbility to massproduce and mass maintain them. The imperium itself has very limited technical knowhow beyond the things their factories can already massproduce.

Besides drama plays a major point in 40k decision making. Lasguns are great, very futuristic but you also want to make sure guard keep that element of drama. That means loud guns, gun that can jam at inoppurtune times (even though laserweapons probably don't even have moving parts) shortages of ammo, none fatal wounds (even though lasguns seem to blow people to gibs one moment and only cause cauterized puncture wounds the next)

Ideally you want all the raw, war is hell drama associated with WW2 / vietnam era war while at the same time getting to use all the cool future tech. So you end up with guns that vary wildly in effectiveness while breaking the laws of physics as needed.

Iuris
07-02-2010, 15:51
If the laserbeam is hot enough to superheat the air around it, it will most definitely create a boom. It's exactly the same effect that makes lightning boom.

In my private 40k world, lasgun beams are invisible since a laser wavelength that is not absorbed by air is chosen, lowering the amoung of energy lost to atmosphere and not letting the enemy know where the shooter is :)

Quadros
07-02-2010, 16:01
Yeah, I know giving all guard boltguns would be silly, and you need that drama and stuff. But my point is basically centred on snipers. I think snipers could be given them, especially if plasma guns and meltas are readily available and even sergeants are running about the place with bolt weapons. Snipers are similarly specialised and highly skilled guardsmen, there are typically what, five at most attached to a company? Compared to up to ten heavy weapon troopers? Besides, a customised bolt action (get it?) bolt gun optimised for accuracy with a nice long snipery barrel would be cool. And the point about lasguns needing to be not so effective would play into this scenario because part of the drama of the sniper is the 'one shot, one kill' thing they'd undoubtedly achieve with a bolt round on a non-superhuman target.

snottlebocket
07-02-2010, 16:34
Yeah, I know giving all guard boltguns would be silly, and you need that drama and stuff. But my point is basically centred on snipers. I think snipers could be given them, especially if plasma guns and meltas are readily available and even sergeants are running about the place with bolt weapons. Snipers are similarly specialised and highly skilled guardsmen, there are typically what, five at most attached to a company? Compared to up to ten heavy weapon troopers? Besides, a customised bolt action (get it?) bolt gun optimised for accuracy with a nice long snipery barrel would be cool. And the point about lasguns needing to be not so effective would play into this scenario because part of the drama of the sniper is the 'one shot, one kill' thing they'd undoubtedly achieve with a bolt round on a non-superhuman target.

The real question is why do they even need snipers. Even in a craphole like the necromundan underhive tracking bolts are reasonably easy to find. (basically a common boltslug with a small tracking computer that will literally fly around corners to get it's target)

Col. Tartleton
07-02-2010, 16:59
The problem is that GW plays up the wrong archetypes every time. They think it's cool. It is cool... IF YOU DON'T REALLY THINK ABOUT IT.

Marines should be all about shooting. I don't think people realize what they're armed with. A bolter isn't just "A really big smg" that "explodes in stuff." But they play it down so that they can get in their chainsword duels... (shakes head)

A space marine is trained for years around the clock in things like marksmanship and tactics. An American Army Soldier, arguably one of the best trained in the world takes 17 weeks from start to finish... Marines are considered even harder trained and they have 13 weeks and then 3 months of (so say 26 weeks total) Navy Seals arguably the best trained in the world have 7 weeks of Navy Basic, 18 weeks of Seal Training plus approximately 18 months of training with their unit before a deployment. But thats a year or two of training for the greatest soldiers in the world.

Marines are trained for what must be several times that and even harder.

So that's what's holding the gun. Then you have to remember what this "Boltgun" is. Its an assault rifle equipped with a machine spirit (Internal Computer) linked to the marine's nervous system and multi spectral optics. So I don't think the aiming can be any more accurate. Then the round itself is a rocket propelled presumably self correcting caseless round approximately .75-1.0 inches in diameter which puts it in the same grade as the autocannon found on a Bradley Infantry Fighting Vehicle. This weapon can be fired from the shoulder or the hip easily however as opposed to supported by a light tank.

The rounds are both high explosive and armor piercing which makes them highly lethal to anything from a swarm of rippers to the lighter armor on most vehicles including tanks. Presumably a Marine could disable an entire armored company from a mile away. 10 tanks, 30 bolts per magazine of which there are several. I'd imagine a single well placed bolt down the large bore of an Imperial tank barrel or into a joint in the turret would damage the mechanisms severely. Another round to disable a tread and the tank is now a sitting duck for a marine with an anti tank weapon to then properly remove from combat. The marine has his tiny silhouette (He is remember a tank, not a soldier for the purposes of this discussion), available cover, and ease of mobility to make direct counter fire an exercise in futility, and any near misses will be woefully unable to to pierce his ceramite.

spetswalshe
07-02-2010, 17:04
A bolt round is kind of like a miniature rocket-propelled grenade. While it might well make an effective sniper weapon, you're ultimately taking away some of the basics of the 'sniper' trope - shot placement, windage and the like (I can well imagine bolts programmable to counter strong crosswinds), plus I would imagine they'd be harder to supress.

While I would argue that boltguns aren't the 'stubbers' that snottlebocket meant (since they fire explosive rounds, they'd have more in common with automatic grenade launchers than an autogun or stub pistol), I'd also question, if we're going to be bringing it up, the recoil. I've read reverse-explanations of a bolt's recoil as due to a kicker charge, but that doesn't wash with the idea of them putting out the kind of recoil that makes them unusable for normal humans, especially with a .75 round size.

Do we have a good idea on a bolt's actual range? One could imagine the motor burning out before 'sniper range'. Though, of course, the Space Marines, armoured shock assault troops that they are, get to do sniping (Telion with his regular-length gun, for one), just like they get to do everything else.

(if you're shooting a guy at extreme range then giving you that implant that means you can spit poison might have been a waste of time)

MarcoSkoll
07-02-2010, 17:19
Besides, a customised bolt action (get it?) bolt gun optimised for accuracy with a nice long snipery barrel would be cool.
While I don't even pretend my witterings are anything close to canon, I've actually used this idea in the "Revised Inquisitor Armoury", a project of mine where I'm slowly putting more depth and more nods to accuracy into the firearms for Inquisitor.

One of the things amongst the collection is essentially just that - a boltgun designed for better long range accuracy. Given the rarity of bolts, using them more sparingly in a single shot rifle rather than spraying them on full-auto should happen more often!
Of course, I accept the possibility that bolts may just not remain stable over long distances - the projectile design is not really going to be too conducive to long range accuracy. However, over relatively short ranges, perfectly acceptable, and I can see them being used by Arbites Snipers or other such roles.

However, to counter your "Long-las are boring" point:
Eliminating all of that bullet drop, wind and drag is VERY important. While you can learn all the trajectory for one planet, go to another one with different gravity or a less/more dense atmosphere, and all of your knowledge goes out of the window.

If I may be immodest, I'm a damn good shot. However, put me on Mars or the Moon, and all of my knowledge of the trajectories my various firearms have on Earth would be immediately rendered useless.
I understand the underlying principles of trajectory very well (Ballistics is my job!), so I could probably make much more educated guesswork as to where I might hit than the average Joe, but I'd still find it near impossible to make good shots at any real range unless you gave me a good long time to practise.

In the end, an awful lot of the challenge of sniping is not just trajectory, but also simply being able to handle the weapon precisely enough.
I know, as I had to learn both parts of shooting. Knowing where my aimpoint should be for the given wind, range, velocity, drag, etc is irrelevant if I can't actually hold aim on that point and fire accurately. Even to this day, I know my trajectories better than I can shoot to them.

Cutting out all of the education that would be needed on trajectory and how it changes across planets and just giving a sniper a "rifle" where he only needs to be able to "point and click", while it might be less badass, makes one HELL of a lot more sense for an army which will be called upon to fight on many different worlds.

In this case, I'd argue that Abnett has got the right end of the stick - perhaps not intentionally though.


We have at least one example of Dark Eldar dodging las-bolts in the fluff before. So does that mean Dark Eldar are FTL?
Dodging a bullet after it's fired isn't really possible, even for Eldar - it calls for movement speeds even they couldn't really conjure up.
Instead, to quote Dr McNinja: "The problem with your gun is you have to point it where you want to send the bullets, and I can see that!"

The trick here being to dodge not after a shot is fired, but before - simply don't be in the way of the muzzle when something comes out of it, be it at 500 m/s or 299,792,458 m/s.
Sure, the tiny time difference that it takes the slower bullet to reach you might improve your chances of dodging fractionally, but for the most part, you could dodge a laser beam nearly as effectively as a bullet.


Do we have a good idea on a bolt's actual range? One could imagine the motor burning out before 'sniper range'.
The motor running out of fuel wouldn't suddenly cause it to stop in mid air - it would just represent the point at which the round stopped accelerating, and started decelerating instead.

And as it's a heavy, dense projectile travelling at very considerable velocities, it's going to take it a long while to decelerate.
As I point out above, their effective range might be limited by their inherent accuracy, but I can't see fuel capacity being an issue.

Quadros
07-02-2010, 18:14
Yeah, that was my point really. Having a gun that doesn't need to worry about wind and trajectory would be great for the guard. But Abnett writes about wind and trajectory in relation to a gun which just wouldn't be effected by it, that's my beef. Not the gun itself, but the inaccuracies intrinsic to it's portrayal.

Lupe
07-02-2010, 18:19
See, my understanding of physics is rudimentary at best ('a' in science at GCSE five years ago, check me out!) but as far as I can tell, a long las shot is still a laser, and thus still light. A thread on the matter on lasguns in general seems to back me up on this. And thus the problems begin. Because a laser is light. Light doesn't have mass. And therefore it's not going to be effected by wind, or gravity. even the target's movement will have a negligible effect, As long as the cross-hairs are on the target when you fire, at any manageable range the impact will be pretty much instantaneous. (I'm assuming here that lasers still travel at the speed of light, since that's what they are and stuff.)

I can't really explain that either, unless photons would be dramatically affected by air friction. Could be that wind or gravity affect the sniper's body rather than the bullet, but heck, that's a long shot (pun intended).


Most frustrating for me is the passage where that blood pact sniper hears a las shot, thinks he's shot the saint, but then nessa's round hits him. Yeah, very dramatic Abnett, but light travels faster than sound. He's going to be hit way before he hears the shot.


Kill shots don't necessarily mean you black out instantly. Some vital organs can, when damaged, kill you within seconds (I believe the gall bladder, if hit when full can flood your intestins with toxins that instantly poison your blood stream, resulting in death within seconds. At least that's what my freshman med student mate claims)
Saul could have been shot, then heard the sound, then realized he was hit, before some internal organ finally gave in.

TrooperTino
07-02-2010, 18:30
Funny... I changed all the laser-references from abnett for the snipers to solid ammo in my mind :)

snottlebocket
07-02-2010, 18:43
I can't really explain that either, unless photons would be dramatically affected by air friction. Could be that wind or gravity affect the sniper's body rather than the bullet, but heck, that's a long shot (pun intended).


Wind and gravity don't but atmosphere does. Lasers are light and anything that blocks and refracts light will diminish the effectiveness of a laser. Our current laser technology is certainly affected by atmospheric disturbances like clouds, dust on the wind and so on.

Cromwell Haarlock-Leth
07-02-2010, 18:47
Well, what surprise me is that the IG needs specific snipers. They need scouts, able to find a way to the target to-be-killed.
After that, they can easily shot him, because they got lasers. Lasers are not affected neither gravity, nor by wind, rain or whatsoever.
Besides this, i'll make a silly explanation. If a guy standing in Paris, France, could see (I know it's impossible, it's just a distance exemple), and thus shoot a guy in New York, United States of America, the laser beam would need 0,00002 seconds to hit him. No time for any kind of move. A highly trained athlete has a reaction time of 0,25 second. 10 000 times more...
And, if any sound was emited by the lasgun, it would reach the now dead body roughly 5hours after his death!
The only thing you got to do to shoot a man with a lasgun is to see that man, point your lasgun at him, and be sure you're not shaking, to keep him in your light of sight. After that, he's no chance left.
It's maybe not very dramatic, but very effective. And that's the point in improving weapons, no? Why would you use a slug weapon, a needle weapon or a boltgun, all of which affacted by weather conditions, when you can use a far more effective laser beam?

Horus_Lupercal
07-02-2010, 18:54
abnetts lasers arent really lasers they have recoil richochet and are affected by wind and such. a hotshot is a liquid metal one shot pack maybe two shot pack so it makes sence that it would be affected by wind and such.

Bunnahabhain
07-02-2010, 18:58
Having a weapon capable of hitting the target accurately and instantly , like a lasgun, is all well and good, but useless if you're not trained to use it that way, or it doesn't have the power to do much when it hits...

If I was a 40k sniper, I wouldn't bother with any other above mentioned options. If I can see a target I can kill it, and would use either:
A lascannon. Like a long las, but better.
or
A laser target designator, and an artillery battery/air support.
One shot, one kill, but 40k subtle.....

Cromwell Haarlock-Leth
07-02-2010, 19:12
abnetts lasers arent really lasers they have recoil richochet and are affected by wind and such.

Sorry. I know what he wrote, but, still, a laser is a laser.
If Dan Abnett, although having written many of the best BL books, IMHO, sometimes forget what is writing about, it is not our problem here. We are not only speaking of Abnett's lasers.


a hotshot is a liquid metal one shot pack maybe two shot pack so it makes sence that it would be affected by wind and such.

The super-charged power cell used for hot-shot use liquid, that'all. By no way your lasgun fire anything liquid through its lense!:eyebrows::cries:

@Bunnahabhain: Laser cannon are too heavy to carry, but I truely like your second version. Very, very light handed... I f you can use your 406mm heavy turret to "snipe" a target locked by laser designator, it's certainly the best Imperial Guard way to have the job done!

Cheesecat
07-02-2010, 19:26
Or just give him a solid slug weapon, there are enough of them about, aren't there? It's not like solid ammo weapons are defunct in the 41st millennium, is it?



There is a solid slug sniper rifle it's called the Exodus Rifle.

Bunnahabhain
07-02-2010, 20:49
Lascannon are certainly not too heavy to carry.

The background bible- ie second ed core books- says they are the heaviest of the man portable heavy weapons, and heavy weapons teams seem to manage them somehow. Snipers normally operate as a sniper and a spotter, so should be able to manage it.

That being said, I'd still look for a stripped down version. Lose some cooling, so it can't shoot as fast, carry less ammo, and hopefully it will then be light enough to use a bipod, rather than heavy tripod.
The Russians in WW2 kept using their outdated Anti-tank rifles despite only being able to penetrate light vehicles, as it made for a fairly effective sniper rifle- a minimum weigh of 18 kg, before ammo, spare barrel etc, etc. 14.7mm rounda, and 2 m long. Not a small weapon!

Still oversized and overkill for a sniper weapon, but all 40k weapons are oversized...

Cromwell Haarlock-Leth
07-02-2010, 21:06
@Bunnahabhain: what I wanted to say is that a scout who try to infiltrate the enemies ligns may not want to carry such a big and cumbersome weapon.
Your shorter version, with reduced rate of fire, seems very appaeling to fit that role.
Concerning the 14,7mm anti-vehicle rifle: Oversized? maybe... Over killing? Well, if we're speaking from the Imperial Guard... What could best defines the IG than the "over-killing" expression?

MarcoSkoll
07-02-2010, 21:17
But Abnett writes about wind and trajectory in relation to a gun which just wouldn't be effected by it, that's my beef.
Well, I've not read the books, but if that's so, that's pretty silly.

~~~~~

I meant to double back to the needler point as well. Although they're supposed to be a laser/needle combination, the former part is pretty irrelevant.

Get a fine needle up to enough velocity, and you'd be surprised how much it can go through due to the concentration of energy on such a fine area.

I've seen conventional sewing needles go through 2 or 3 mm thick steel at very modest velocities - get a proper adamantium needle up to a few hundred (or even a few thousand) metres per second, and it'd go through armour like a hot knife through butter.

~~~~~

@Bunnahabhain: Snipers need to be able to hide and move on quickly. Using a bulky weapon capable of knocking out battle tanks is not exactly fitting with that!

Perhaps you might use something similar for very long range shooting, but Long-las are already weapons with much more power and range than a conventional lasgun - easily as capable and lethal as any modern sniper rifle, if not more so (without getting into anti-material calibres).

Wolfblade670
07-02-2010, 22:43
Actually the idea of using a lascannon as a sniping weapon isn't too far fetched, Carlos Hatchcock used an M2 .50 cal with a telescopic sight to score some of his kills.

MarcoSkoll
07-02-2010, 23:43
While I'm aware of Hathcock's use of the M2, it is not an anti-tank weapon.
Anti-Personnel, Anti-Aircraft, potentially taking out even light armoured carriers, but it just doesn't offer any threat to an MBT (main battle tank).
The closest 40k equivalent has got to be the Heavy Stubber - many of the models of the Heavy Stubber even heavily resemble the M2.

If we want to talk about "far fetched" (and I'm not trying to be funny/rude) trying to compare the M2 and a Lascannon is certainly going that way. Yes, they're both "heavy weapons", but they're heavy weapons at completely different ends of the personnel/armour spectrum.

And in the end, Hathcock used a modified M2. What he used wasn't so much a heavy machine gun as the first large calibre sniper rifle - and a pretty impractical example at that.

Credit for you for knowing about it (I was wondering if anyone was going to bring it up), but not really a very realistic comparison.

Bunnahabhain
08-02-2010, 01:14
I'm aware that fire and relocate is proper practice for a real sniper, but 40k really doesn't work for this. Snipers forming dedicated units of 6-10... why oh why oh why....
If we renamed all the snipers we have on the battlefield as sharpshooters, we would have game space for real snipers...

I had brought up the 14.7mm Russian AT rifle earlier. Think it just about qualifies as very heavy sniper rifle, in use, if not design.

Karl MkVI
08-02-2010, 03:38
We have at least one example of Dark Eldar dodging las-bolts in the fluff before. So does that mean Dark Eldar are FTL?

as amusingly-put rhetorical questions go, this is one of the best I've ever seen. :D

kudos, sir.

Gutlord Grom
08-02-2010, 04:12
I'm aware that fire and relocate is proper practice for a real sniper, but 40k really doesn't work for this. Snipers forming dedicated units of 6-10... why oh why oh why....
If we renamed all the snipers we have on the battlefield as sharpshooters, we would have game space for real snipers...


Actually, fun fact, but I found out recently that the U.S. Marine Scout Snipers (I think) are buffing up sniper teams to five men for a few reasons: more guys to carry supplies, more people for site security, easier to keep watch with a larger team, more potential shooters for a high value target etc.

So five man units of Scout Snipers, Rangers, and ratlings are not completely unreasonable.

Mr Zoat
08-02-2010, 06:26
2nd ed wargear book makes it pretty clear that las weapons aren't laser weapons as we would understand the term.

wilsongrahams
08-02-2010, 08:25
Very little has been made about the statements a few others made that lasers are in fact affected by the distances etc involved - though more due to moisture in the atmosphere than anything - rain will dance that light beam all over the place and in now way in a predictable manner. Also, there should be a very loud crack from every laser weapon fired, seeing as it is a solid beam of particles in some way, and unless it is just pure light, it will have to be to inflict damage, and so will cause a sonic boom just like lightning does. A laser that is a beam of light, is very different to what people think a laser weapon really is, which is actually more akin to plasma weaponry from 40k. In fact a YAG laser is almost identical to the descriptions of plasma weapons - energising gas and then using a magnetic accelerator to speed it up and squirt it out at one end.

It is more twisted in that what is described as being a plasma weapon in 40k, seems to function more like a fission reaction of gas particles - like what happens in our sun when hydrogen atoms are forced together.

Back to the original question - I actually imagine 40k laser weapons to be very similar to the star wars blasters - which are kinda like plasma weapons really too. They have the familiar 'bolt' rather than a continuous beam, which is how lasguns etc seem to be described, and the recoil comes from the force of pushing against a mass which is the molten plasma to expel it from the weapon - remember, real lasers don't have a mass so no recoil (okay so they do but it's negligible!).

I hope this helps someone else to settle things in their minds, and that it's more a mix of terms than incorrect physics.

NightrawenII
08-02-2010, 09:11
Its amusing how many people base their imagery of las-weapons on the light pointer. Anyone who use/used words "light" and "las-weapon" in the same sentence need to refit their ideas about las-weaponry. Light doesn't make holes in the people.;)

just my two cents.

Cromwell Haarlock-Leth
08-02-2010, 09:33
@ Nightraven II:
Laser means: Light Amplification by Stimulated Emission of Radiation, did you forget?
So, yes, I put "light" and "laser weapons" in the same sentence.
Actual industrial lasers cut trough steel, and they are nothing but light.

Karl MkVI
08-02-2010, 09:37
Actual industrial lasers cut trough steel, and they are nothing but light.

see, this is the sort of knowledge I would love to throw at people who start threads like "40k weaponry is worse than present day". no, it's not.

thank you Cromwell, my day is made and its only half ten.

wilsongrahams
08-02-2010, 10:18
Its amusing how many people base their imagery of las-weapons on the light pointer. Anyone who use/used words "light" and "las-weapon" in the same sentence need to refit their ideas about las-weaponry. Light doesn't make holes in the people.;)

just my two cents.

Having worked in a laser manufacturing facility, and used a laser designator in the army, I restate that the problem is that the term 'laser' actually covers more than one type of item. Those laser pointers are in fact very similar to what many people think lasers are, whereas in reality, lasers range from a light bulb and a set of mirrors, to a plasma cutter etc, and the terms get confused in 40k.

As for using the term light and las-weapon in the same sentence, it depends upon the sentence, because plasma (which is basically just charged ions, we're not talking the bodily fluid type here) does emit light when excited, and when 'fired' by say a series of electromagnets becomes a beam, which is how a laser cutter works. depending upon the gas used will give you a very hot beam or an almost pure light beam which has no temperature - the difference here being that different gases will need different temperatures before they break their bonds and start emiting electrons all over the place.

Cromwell Haarlock-Leth
08-02-2010, 10:40
@wilsongrahams:

Thanks for the explanation.:)
As you seem to know this subject far better than I do, could you tell me/us at which speed travels a "plasma laser" beam (what you described)? And what sounds it emits?

Bunnahabhain
08-02-2010, 12:58
All true lasers will travel at the speed of the light, regardless of wavelength.
Any sound they produce will be due to either mechanical action in the gun, like the way a proper camera shutter clicks, or more significantly, a crack like lightning, from the beam super-heating the air it passes through..

A plasma cutter produces a fairly slow moving beam. Given they work off a physical media being accelerated, then being ionised to a plasma, I'd expect it to be no more than a few hundred meters per second. They also have a practical range of 300mm ( yes mm) or so at the moment...

If it is one of the types that uses a plasma to produce a laser beam, and it is the laser that is used for the cutting action, then it effectively defaults to being a laser, as above...

tsutek
09-02-2010, 00:27
I always thought las-weapons to be the same tech as plasma weapons. Only difference being the energy delivery pattern - more concentrated in las-weapons (smaller holes/longer ranges), less concentrated in plasma (bigger holes/shorter ranges)

and las != laser.. Even I know my 40k that much :)

Bunnahabhain
09-02-2010, 00:40
Nope, everything in the background that directly address it says las weapons ( las pistol gun, multi-laser, lascannon, eldar equivilents...) are true lasers, and cause damage via a a burst of co-ordinated radiation, of a specific wavelength. (If this confuses you go look up what a laser is on wikipedia...)

Certain Black Library authors, and DoW programmers may not know how a laser behaves, so include descriptions that make no sense. Ignore them.

kanluwen
09-02-2010, 01:00
It almost seemed like part of the complaint from the OP was because Larkin uses the standard shooting techniques(steadying breathing, settling in, etc).

I don't see any issue whatsoever with that. Aiming a laser weapon is just as important to AIM CORRECTLY like aiming a modern sniper rifle.

Quadros
09-02-2010, 01:24
It almost seemed like part of the complaint from the OP was because Larkin uses the standard shooting techniques(steadying breathing, settling in, etc).

I don't see any issue whatsoever with that. Aiming a laser weapon is just as important to AIM CORRECTLY like aiming a modern sniper rifle.

How does it seem like that? I'm fine with him emptying his lungs and settling in, and baffling the barrel. Yeah, aiming a sniper rifle as accurately as possible is always going to be crucial. I specifically mentioned his considerations about bullet drop and the effects of wind and movement, because those are the things that wouldn't matter.

I'm not trying to bad mouth Dan Abnett by the way, I think he's great and if someone was to insult him I'd leap to his defence in rabid fanboy mode. I guess part of my point is that his normal attention to detail makes this slip just a little bit more annoying. Plus it took me like 5 years to spot it, and normally I jump on a plot inconsistency as soon as it appears in front of me yes Emmerich that's aimed directly at you.

kanluwen
09-02-2010, 01:47
Frankly, that was all I was really able to glean from your OP. You were all over the place, talking about solid slug weaponry(which Larkin *has* used, and *does* possess as a back-up. He has a single shot, bolt action that he 'liberated' from the Jantine in "First and Only"--but seems to prefer his long-las, which he customized himself quite a bit) and the physics of lasguns, etc.

Simply put:
A lasgun *would* still have a snap-crack due to superheating the air.
While on the subject of lasguns, I do want to point you towards a different series of fiction--the Republic Commando novels, most specifically "True Colors", in which a device called a LIS(Laser Inhibition System) is utilized. Simply put--it's a chemical smoke grenade that bends light(which what are lasers?).
I'd not put it beyond the 40k universe to have something like that, or any number of factors(ever seen light refract off dust particles being blown in the wind? Cause that'd be a fantastic reason to understand the windage...) being the reason why the truly *expert* snipers like Larkin are a cut above the rest.

But yeah, talk about incoherent posts there^.
Your OP just didn't make much sense to me, and that was only the really big point that stuck out to me.

thearchiver
09-02-2010, 05:10
Just a thought, but would a longlas, make it easier to aim more precisely than the shorter lasgun if firing from a prone position?

MarcoSkoll
09-02-2010, 12:55
A lasgun *would* still have a snap-crack due to superheating the air.
Superheating is very much the wrong term - Superheating has a very specific meaning in physics, and this is not it.

Heating, yes. Ionising, yes - it's the only way I can see they could practically work. Superheating, no.


ever seen light refract off dust particles being blown in the wind? Cause that'd be a fantastic reason to understand the windage...
No, it wouldn't really. If you consider they're just like a laser pointer (which as I explain below, they are not) the light you're aiming by is affected in just the same way as your beam. If light will curve on the way to your target, it's curved exactly opposite on the way from your target to you. Simple as.

I don't quite see how people can be arguing "but what if the light bends" and completely overlooking the fact that the aiming in the first place is dependent on light travelling through the same air!

But these lasers just can't work in the same way as a typical laser pointer. Their power would be enough to simply ionise and shunt the air in their way out of their path - so they wouldn't refract in the same way as less powerful light sources. In other words, they shoot entirely straight, free of any interference.

If the light you're aiming by hasn't travelled straight (usually only the result of mixed air densities in the atmosphere), then that might upset things a bit, but if we're arguing about light bending, the issue is the light you're aiming by bending, not the beam itself.

And that problem applies to any firearm, light based or projectile based.

wilsongrahams
09-02-2010, 13:52
I agree, superheating is wrong - that applies more to say steam in a power station to run more efficiently rather than what I think you meant, which was very fast heating of the air.


@wilsongrahams:

Thanks for the explanation.:)
As you seem to know this subject far better than I do, could you tell me/us at which speed travels a "plasma laser" beam (what you described)? And what sounds it emits?

I think you already got your answer but didn't want you to think I ignored you.
The problem here to do with speed is that the plasma is emitting particles that travel at the speed of light, and die just mm away from it, but the mass of plasma itself will only travel as fast as you can accelerate it using saying electromagnet coils. This could theoreticaly be at the speed of light, but just like a Rail Gun, the problem is getting the mass of the plasma or slug to follow the electromagnetic pulse at the speed the pulse travels at. This is because you need a gas to create the laser, and really you want to either fire the gas as a plasma burst or fire the laser alone which is just a beam of light and will in effect do nothing apart from bounce off things under most circumstances. This is why a laser or plasma cutter are both very short ranged currently. Laser cutters, ion cutters and plasma cutters are all the same technology at the moment just by different names.

Where a laser does become powerful when just a beam of light is due to heat in the same way as a magnifying glass will focus at a point and melt things - this however is an invisible laser and doesn't match the fluff descriptions of 40k las weapons - which was why I said they were more like plasma and star wars blasters...

There is no 'bolt' with a light laser, and then you are edging towards the microwave/multi melta technology, which I'm guessing is a different matter.

Cromwell Haarlock-Leth
09-02-2010, 14:17
II think you already got your answer but didn't want you to think I ignored you.

Thanks:)
And also for the technical explanation.

Fallenity
09-02-2010, 15:12
As if the laws of physics have not been already broken a dozen times in the 40k fluff.

But all this is still very interesting ^^ I didn't know that laser technology could have such a strong application in modern warfare already. Of course laser guided missiles etc are common knowledge, but that you can already deliver lethal amounts of energy through lasers in a warfare setting? Neat

Although I did hear something a while ago about the US military trying to create anti-air and anti-missile weapons based on laser technology.. Don't know how that's worked for them.

Maybe sci-fi battles of lasers (whether invisible or not) is not a hundred years away, but perhaps already in 30 years! Don't know then if this is a good thing or not =D

wilsongrahams
09-02-2010, 15:24
You're right. This was started in the 1980's and was unsurprisingly called the Star Wars Project by nickname, and was mainly involving satellites in space with lasers in them.

Laser technology can bu used as it is today, just like rail gun technology. I'm pretty certain there are designs drawn up for rail guns on some of the future classes of US Cruisers or Destroyers or whatever. The problem, is that they need a HUGE amount of energy. For an infantry rifle, you'd need a battery the size of a caravan I was told somewhere... As for lasers, they usually function by bouncing a beam between two mirrors until it has enough energy to pass through a mirror and fire off at whatever it's aimed at. The problem here is that to get a lot of energy into that beam it takes a lot of power and a lot of time to accelerate it up, and so you end up with a longer lasing chamber. For a medical laser today cutting at up to 30mm you have a chamber 60cm long. To fire 1km, at that ratio, a laser would need to be 20m long. I'm no expert and the maths could be different when scaling etc and boosting the power (I no nothing about military lasers, just industrial and medical) but that is a very large and fragile weapon if you ask me. This means that to me lasers will at best be left to ships, tanks and aircraft with the infantry still firing bullets at each other, whilst wearing a suit made of mirrors to keep them safe!

MarcoSkoll
09-02-2010, 15:33
I'm pretty certain there are designs drawn up for rail guns on some of the future classes of US Cruisers or Destroyers or whatever.
More than just designs. Prototypes. (http://www.youtube.com/watch?v=ZourRsUsnho)

wilsongrahams
09-02-2010, 15:43
Thanks. I thought there had been but didn't want to say so without knowing for sure. Afterall, I once woke up from a dream where I could fly and it took me ages to realise it was a dream! (I was very young).

Fallenity
09-02-2010, 17:29
This means that to me lasers will at best be left to ships, tanks and aircraft with the infantry still firing bullets at each other, whilst wearing a suit made of mirrors to keep them safe!

I knew about the Star Wars Project, but for some reason remembered it was supposed to use missiles instead of lasers >.<; So much for studying 20th century history for 3 years.. But I think I saw a show on tv that discusses new weapon technologies, think it was called Future Weapons or something. They had an episode about US military using lasers as anti-missiles, but the laser "cannons" were land-based. Anyone ever heard of that?

Then again, could be just that they were guiding lasers for anti-missile missiles... >>; My memory plays me for a fool.

How viable would a mirror be as a defense from lasers? :D

While I'm pretty sure it doesn't work that way and would look very comical, aren't the physics behind it? Lasers are light and mirrors reflect light.

I guess it depends on if there are 100% reflective mirrors. If the mirror just reflects 99% of the energy, the 1% still causes damage.. But I guess even then it would be a viable defense against lasers.

Of course the practical problems of building a mirror covered suite would be big. And I still think it's always better to dodge the shot then try to take it on armor. Or even better, don't let the enemy see you :D

But with the rise of thermal equipment, I guess camo loses its meaning in the future..

Sorry for the illogical structure, just writing my train of thought :)

wilsongrahams
09-02-2010, 18:56
The problem is that a mirror doesn't reflect 100% of light - that's why it appears darker than 'real life'. The issue here is the metal used in the backing - metals are grey not white. If you could have say a pure white metallic substance then it'd work better. As it is, the minor amounts of black making up that grey absorb the heat and so just like the sun warming a mirror but reflecting most of it away, so too would a laser of sufficient power damage the mirror.

And yes I too have seen those programmes about lasers to shoot down missiles, and Tom Clancy wrote a whole book about them!

Tonberry
09-02-2010, 19:26
In the 41st millenium, C is no longer a constant.

It is instead applied in such a way as C=Io+N/Roc

Where:

Io = the authors intended outcome for any given scene involving lasers
ND = the authors need to add in some sci-fi elements so the story does not read like a WW2 drama novel
RoC= Rule of cool.

'C' can also be drastically changed (up or down) by something known as the 'Mkoll factor', whereby certain individuals can achieve super-human feats simply by being awesome.

Fallenity
10-02-2010, 10:02
The problem is that a mirror doesn't reflect 100% of light - that's why it appears darker than 'real life'. The issue here is the metal used in the backing - metals are grey not white. If you could have say a pure white metallic substance then it'd work better. As it is, the minor amounts of black making up that grey absorb the heat and so just like the sun warming a mirror but reflecting most of it away, so too would a laser of sufficient power damage the mirror.

And yes I too have seen those programmes about lasers to shoot down missiles, and Tom Clancy wrote a whole book about them!


But is it possible to create 100% reflective mirrors? That would have to look pretty interesting on a molecular level.. I can't remember for sure, but aren't current household mirrors something like 95% reflective? So you'd imagine that it is possible to improve from that.

Also even if we can't create 100% reflective mirrors, wouldn't a 99% be still an effective piece of armor, it would just "wear down", since I doubt 1% of a "laser blast" would effectively pierce the mirror, the backing and any padding/solid armor underneath.

Of course such "mirror" armors would only be effective if someone suddenly forgot how to make solid ammo weapons that would break the mirrors :D

borithan
10-02-2010, 11:39
How viable would a mirror be as a defense from lasers? :DWell, making a surface more reflective would act as a partial protection. Some proportion of the energy would be reflected away, reducing the amount being exerted on the surface. One suggested way to reduce the effectiveness of "anti-missile lasers" is simply to polish the surface of the missile. Now, as others have said it would not be perfect, and depending on how reflective the surface is (and what it reflects), it would only provide partial protection. However, this would mean the theoretical laser would have to hit the target for longer the do the required damage. A similar idea is simply to spin the missile (as the laser will end up not striking the same spot, spreading the energy across the missile, again resulting on greater dwell times required to do whatever they are going to do).

MarcoSkoll
10-02-2010, 12:42
After all, I once woke up from a dream where I could fly and it took me ages to realise it was a dream! (I was very young).
Oh, I've had that. What's more disappointing (and still happens) is when I've made a large amount of money in a dream and it takes a few seconds after I wake up to realise that dream money isn't of any use in the real world.

As far as mirror armour - well, there is already a canonical "anti-las" armour, "reflective". To quote from the Inquisitor rulebook:
"Often called reflec armour, this contains micro-crystals which help to redirect and dissipate laser bolts, lessening the intensity of their impact. Such armour counts as being D6 higher against lasweapons (rolled each time a location is hit)."
(For comparison, a typical armour value is of the order of 3 to 6 points - assuming the location is necessarily armoured at all.)

... so really, more a description of a refractive crystal coating than anything reflective, but no matter, we can assume it's simply a misnomer.

However, the implication is that it's not something that can be done on a mass scale - perhaps for cost, material rarity or whatever reason.

Bunnahabhain
10-02-2010, 12:50
Neither spinning nor mirrors are likely to be effective defences...

Mirrors would work, if you know what wavelength you're trying to reflect. If you're trying to find a mirror to bounce off Xrays, hard UV, and visable lght, you have a problem.
I don't know that much about the current state of weaponised lasers, let alone in 40K, but it's a big and fundamental problem with mirror defence. If all laser settle on a narrow wavelenght band, then it becomes practical.

Spinning also has a big problem. If your laser delivers a short, intense pulse, as most of the practical looking systems do, then you need to spin the object very fast to spread the pulse to a significant degree. If you spin it very fast, then you need you make it very strong, to prevent centripetal force tearing it apart. It also means you can't use it on something containing passengers - you're tough Mr marine, but 100,000 g as we spin up your drop pod to stop the orbital defense laser knocking you out of the sky will still reduce you to paste.

Just spinning the out layer might be possible, but that's going to be a complex and fragile mechanism.

MarcoSkoll
10-02-2010, 14:23
Mirrors would work, if you know what wavelength you're trying to reflect. If you're trying to find a mirror to bounce off Xrays, hard UV, and visable lght, you have a problem.
I don't know that much about the current state of weaponised lasers, let alone in 40K, but it's a big and fundamental problem with mirror defence. If all laser settle on a narrow wavelenght band, then it becomes practical.
One other possible point to bring up is that "mirror armour" that works in the visible spectrum would automatically preclude the use of camouflage.

You could argue "But it'll look exactly like its surroundings", in doing so, that would be forgetting that HUGE amounts of effort go into reducing reflections in real world combat - as reflecting the sun at your opponents will immediately get you spotted.
I know from experience how important reflections are in military exercises - I spent several years in the Army Cadets when I was younger, and the number of times I spotted people as a result of reflections was practically innumerable. The flash of a watch screen or glasses... there was even one case where I kept track of the "enemy" in near darkness by points of light reflected off the surrounding scenery - when the point appeared to "blink" someone had moved in front of it. Made all of their camouflage and quiet movement useless.

In short, reflections are very bad news for stealth.

Cover your vehicle in mirrors and while you might have decent protection against lasers... congratulations, you're now driving a moving target for missile launchers and autocannons.

Fallenity
10-02-2010, 15:50
One other possible point to bring up is that "mirror armour" that works in the visible spectrum would automatically preclude the use of camouflage.

You could argue "But it'll look exactly like its surroundings", in doing so, that would be forgetting that HUGE amounts of effort go into reducing reflections in real world combat - as reflecting the sun at your opponents will immediately get you spotted.
I know from experience how important reflections are in military exercises - I spent several years in the Army Cadets when I was younger, and the number of times I spotted people as a result of reflections was practically innumerable. The flash of a watch screen or glasses... there was even one case where I kept track of the "enemy" in near darkness by points of light reflected off the surrounding scenery - when the point appeared to "blink" someone had moved in front of it. Made all of their camouflage and quiet movement useless.

In short, reflections are very bad news for stealth.

Cover your vehicle in mirrors and while you might have decent protection against lasers... congratulations, you're now driving a moving target for missile launchers and autocannons.

Yeah, the role of light reflection in camo was strongly emphasized when I was in the army also. It's funny, when first you spend hours on cleaning and shining our weapons, shining our boots etc... Then the first thing you do when you go to the woods -> spread dirt around.

There is a reason why all weapons in the world are either black or environment-specific camo. =)

borithan
10-02-2010, 17:27
Spinning also has a big problem. If your laser delivers a short, intense pulse, as most of the practical looking systems do, then you need to spin the object very fast to spread the pulse to a significant degree. If you spin it very fast, then you need you make it very strong, to prevent centripetal force tearing it apart. It also means you can't use it on something containing passengers - you're tough Mr marine, but 100,000 g as we spin up your drop pod to stop the orbital defense laser knocking you out of the sky will still reduce you to paste.This was based on stuff I had read for lasers currently available, or in the near future, not far future stuff where lasers as a weapon have been perfected and made practical in size, durability and power to be considered every day items of war. It was also purely about protecting ballistic missiles, ie nothing with any living cargo (and also nothing that had to concern itself with being spotted in a battlefield).

MarcoSkoll
10-02-2010, 18:44
...and also nothing that had to concern itself with being spotted in a battlefield.
Your case does indeed not have concerns about being spotted on the battlefield. However, the original mention of "mirror armour" was not related to cruise missiles, but battlefield use - and I'm pointing out the impracticality of it under those circumstances.

The best defence is not being shot at in the first place...

CamNZ
10-02-2010, 20:50
Yeah, the role of light reflection in camo was strongly emphasized when I was in the army also. It's funny, when first you spend hours on cleaning and shining our weapons, shining our boots etc... Then the first thing you do when you go to the woods -> spread dirt around.

There is a reason why all weapons in the world are either black or environment-specific camo. =)

Well there exists, in labs, new metamaterials which have a negative refraction coefficient for a specific wavelength of light. These materials can channel the light within themselves so that a ring of metamaterial with something else in the middle is "invisible" to that wavelength. This could be used as armour if and only if the exact wavelength of the enemy las weapon was known. As the material would channel the light around the wearer (the object in the middle of the ring), assuming a 3d geometry can be determined which allows all directions to be covered. My thoughts would be rings around the arm and abdomen.

Also light does have momentum and hence recoil when it is considered as a matter wave, the de Broglie wavelength relations can determine it value for each photon. I always assumed a light ricochet was a partial reflection off of a surface.

MarcoSkoll
10-02-2010, 22:40
Well there exists, in labs, new metamaterials which have a negative refraction coefficient for a specific wavelength of light.
Metamaterials are... a little odd. We can't automatically assume the Imperium's technology can support such things (and as I suggest above, even if they can make such things, it doesn't necessarily make it cost effective).
It's possible that things such as cameoline are metamaterials, but I can't say more on their existence in the 41st millennium than that.

Now, as far as I understand, metamaterials are NOT limited to a single wavelength. They have to be particularly well refined to work on short wavelengths (read: visible light, through ultraviolet and beyond - the wavelengths such lasers might use), but they're capable of working on a wide range of frequencies.

However, I don't pretend that I'm anywhere near an expert on them. Ballistics is an area of particular expertise - nanoengineering, not so much.

CamNZ
10-02-2010, 23:43
\
Now, as far as I understand, metamaterials are NOT limited to a single wavelength. They have to be particularly well refined to work on short wavelengths (read: visible light, through ultraviolet and beyond - the wavelengths such lasers might use), but they're capable of working on a wide range of frequencies.


I am going to revise my statement and agree with you in part here, you are correct they do not require a specific wavelength. But the range over which the material is negatively refractive is limited. i.e a metamaterial for visible light will not work for UV or microwaves and vice versa.

Also on a side note, gravity does have an effect on light. But no where near enough for it to have any effect on aiming.

borithan
11-02-2010, 17:24
Also on a side note, gravity does have an effect on light. But no where near enough for it to have any effect on aiming.It should have no effect on aiming wat all, as the light which you are aiming by (the light reflected off the object you are trying to shoot) will have it's path altered by gravity by the exact same amount as your shot going the other way (barring bizarre gravitational disturbances which occur after having take the shot but before it hits).


Your case does indeed not have concerns about being spotted on the battlefield. However, the original mention of "mirror armour" was not related to cruise missiles, but battlefield use - and I'm pointing out the impracticality of it under those circumstances.

The best defence is not being shot at in the first place... Oh, I wasn't disagreeing or... whatever I might have been doing. Just saying that making a surface reflective can act as a partial protection (and has been considered in the past), but agreeing that it was only useful where the problems with it don't matter. My post was just meant as a clarification of the context of my point.

wilsongrahams
12-02-2010, 19:24
I agree - remember that by seeing the target, light is being 'shot' at you after being reflected from it, and will bend in exactly the same way as your laser will fire back. Your barrel may not be pointed at the target in reality but it is pointed where you see the target to be after that bending.

Also remember that light always travels at the same speed, and is not relative so movement etc would not make it any harder ot hit a target - nothing moves faster than light, ever. Even a light particle heading towards a light particle still only sees the other particle closing at the speed of light.

Zoring
13-02-2010, 23:15
Lasguns don't shoot 'light' like a modern laser, they shoot individual blasts, like a star wars blaster. So the are not lasers. Despite the name.

This is mentioned explicetly in the Imperial Infantrymans Uplifting Primer.

Also, when Red Orchestra 2 comes out, play that if you want a proper depiction of infantry combat over MW2

MarcoSkoll
14-02-2010, 00:38
This is mentioned explicitly in the Imperial Infantryman's Uplifting Primer.
Unfortunately, I've got two words I really wish didn't exist as a concept: "Conflicting canon".

Other sources claim the exact opposite. To quote from the Inquisitor Rulebook: "Las weapons work by firing a blast of highly charged light which transforms into heat and kinetic energy upon impact, causing tissue damage and burning."

Actually, do you have a page number on that? I've just looked at my copy of the IIUP, and I can't find any particular reference in the short passage on the lasgun about what it's supposed to fire.
As far as weapons and that kind of stuff most of it is in the Munitorum Manual - and unfortunately, it seems to be somewhat inconsistent even on its own. It starts by mentioning "explosive energy blasts", and then switches back to using "laser".

Lame Duck
14-02-2010, 01:36
Also remember that light always travels at the same speed, and is not relative so movement etc would not make it any harder ot hit a target - nothing moves faster than light, ever. Even a light particle heading towards a light particle still only sees the other particle closing at the speed of light.

Going to be pedantic.

Also remember that light always travels at the same speed within a given material.

But I've found your posts reall interesting clarifying some points I wasn't clear about.

@someone earlier

They asked if given you fire a laser if making it longer would improve it's accuracy.

Two points here. First of all, it would be easier to make sure everything within the gun is parrallel.

Also, just getting it level /keeping it on target would be easier, think about mounting a short shelf vs a long shelf.

SSG Snuffy
14-02-2010, 02:02
@Lame Duck: You're on the right track... in firearms jargon the "sight radius" is the distance between the front and rear sights on a weapon without optics. A longer radius means that small movements at either end of the weapon (or both) translate into smaller effects on the projectile. A perfect example is the difference between a rifle and a pistol. The pistol is capable of shooting a projectile thousands of meters, but pistols are rarely used at distances greater than about 25m. The short sight radius of the pistol makes it too difficult to hold the blasted thing still enough to aim at a smaller target.

A rifle, on the other hand, has a much longer sight radius. Combined with its greater weight, this makes it easier to hold steady and aim at smaller targets.

Optics (telescopes and such) complicate things a bit, but the end result is still the same. A longer, heavier weapon is easier to hold still long enough for precise aiming. At some point, of course, you'll reach critical mass on both length and weight. A weapon that's too heavy or too long is of limited utility in a tactical environment. I'd very much like to have a Barrett M82A1, but I wouldn't want to carry it very far or try to use it in a firefight.

Zoring
14-02-2010, 10:17
Actually, do you have a page number on that? I've just looked at my copy of the IIUP, and I can't find any particular reference in the short passage on the lasgun about what it's supposed to fire.
As far as weapons and that kind of stuff most of it is in the Munitorum Manual - and unfortunately, it seems to be somewhat inconsistent even on its own. It starts by mentioning "explosive energy blasts", and then switches back to using "laser".

Unfortunately no, it is infact in the Munitorium Manual :) Just had a look myself.

Perhaps there are two types of lasguns, one's that fire with a beam and ones that fire with a bolt (although these would mechanically make them quite different weapons) the old Final Liberation game had bolts flying around, whilst Dawn of War has beams.

I just prefer the bolts to the beams personally.

MarcoSkoll
14-02-2010, 11:52
Perhaps there are two types of lasguns, one's that fire with a beam and ones that fire with a bolt (although these would mechanically make them quite different weapons)
While that's a theory, your addendum is the problem here. While it is possible to have two different types of weapons that go by the same name, the important part behind the lasgun is its incredible standardisation.
To quote from the IIUP (pg. 18): "The lasgun is made to the same specifications (with a few variations) all over the galaxy."

To double back to the point I said about "Conflicting canon", if you can provide a source that says there are two different classes of weapon collected under the same "lasgun" name, then there's a discussion to be had on that front instead.

But personally, I take it that they are meant to be laser based weapons, and "explosive energy bolts" is the result of whichever author having watched too much Star Wars.

wilsongrahams
14-02-2010, 15:53
Going to be pedantic.

Also remember that light always travels at the same speed within a given material.

But I've found your posts reall interesting clarifying some points I wasn't clear about.

@someone earlier

They asked if given you fire a laser if making it longer would improve it's accuracy.


Actually light ALWAYS travels at the same speed. It NEVER gets slowed down. What you may be confusing is that different wavelengths (colours basically) of light refrect (bend) different amounts when they pass through different materials. They actually still travel the same speed.

Making a laser longer would do nothing at all, except the fact that by making the weapon longer you have more area to add more magnets etc to accelerate the laser or energise it quicker. Therefore, you can make a more powerful laser, but using the same powerpack etc but with a longer distance between the mirrors etc there is no difference at all.

Glad to help. I'm always getting told everything I read is wasted cos I'll never need it! For the record, I work night shifts and spend them studying for pleasure. Anything and everything but usually history and science.

MarcoSkoll
14-02-2010, 16:25
Actually light ALWAYS travels at the same speed. It NEVER gets slowed down.
Um... the very definition of refractive index is the ratio of the speed of light in either air or vacuum to the speed of light in a given material.
For example, in glass (which usually has a refractive index around 1.5), you would have a speed of light of around (only) 200 000 000 m/s.

There are even some mediums where we can slow down light to very mundane velocities - believe it or not, mere tens of metres per second. The speed of light is a constant in any medium, but it varies between them.

However, as you allude to, refractive index does change with wavelength, meaning that some wavelengths are slowed more than others... and it's as a result of this that things such as prisms work.


Making a laser longer would do nothing at all, except the fact that by making the weapon longer
As has already been mentioned, sight radius does apply (to some extent) here.


you have more area to add more magnets etc to accelerate the laser
Magnets accelerating lasers? Aside from the whole "speed of light being a constant in any medium" thing which makes the idea of acceleration outright wrong, as far as I know, there is no scientific basis for light being affected by magnetic fields at all - it has no charge, and therefore cannot be affected...

MarcoSkoll
14-02-2010, 23:05
how do you know all this scientific crap?
To quote Alun Anderson, a former editor of New Scientist: "Science is interesting - and if you don't agree, you can **** off."

I just find science a subject that really grabs my attention - I like knowing how the universe works, you see.


this is about hot shot lasgun packs for snipers....not the speed of light in different mediums.
No, this is about laser trajectories, to which the speed of light in different mediums is inherently a part.

Iuris
15-02-2010, 06:23
OK, first, I'd like to say that for some reason, this bit of physics almost dropped me off my chair (as in, DAMN, why didn't I think of that):

It should have no effect on aiming wat all, as the light which you are aiming by (the light reflected off the object you are trying to shoot) will have it's path altered by gravity by the exact same amount as your shot going the other way (barring bizarre gravitational disturbances which occur after having take the shot but before it hits).

Second, several sources (Gaunt's ghosts, Dark heresy, ...) indicate that military gear is far from being completely standardized all over the galaxy. Different types of lasguns are to be expected.

Remember, the Departmento Munitorum is a galaxy sized organization. Just look at the variety of technology on the ONE world that we inhabit now and you'll see that if you have a million types of lasguns in 40k, they're remarkably standardized compared to current day military standardization...

808thMyrmidons
15-02-2010, 07:32
its entirely possible that the longlas is a more intense laser than the las gun.
light intensity decreases the farther it travels through a medium and the more reflective particles in said medium. thats why the bottom of the sea isn't bright as day, why you see past your own nose when fog is thick enough, and why it isn't blinding whenever the suns up. now because the intensity decreases after going through a medium you're gonna have a certain kill range which is why a single guardsman with a lasgun can't take out orks from across a 5 foot gaming board. now if a longlas is a more intense laser then it has a greater range and penetrating power than a regular lasgun.
this just my thought on the matter.
i dont know light physics beyond basics if this was about mechanical physics i could probably have a better explanation

808thMyrmidons
15-02-2010, 07:36
Magnets accelerating lasers? Aside from the whole "speed of light being a constant in any medium" thing which makes the idea of acceleration outright wrong, as far as I know, there is no scientific basis for light being affected by magnetic fields at all - it has no charge, and therefore cannot be affected...

while ACCELERATING a laser is bogus a magnet field does have an effect on light.
remember its an electroMAGNETIC wave

MarcoSkoll
15-02-2010, 09:04
while ACCELERATING a laser is bogus a magnet field does have an effect on light. remember its an electroMAGNETIC wave
Electromagnetic wave, yes - but...

Electromagnetic radiation is characterised by the propagation of electrical and magnetic fields oscillating in phase perpendicular to both one another and the direction of energy propagation.

Various asides:
As a result, the speed of light in a medium is equal to the reciprocal of the square root of the product of the electrical permittivity and the magnetic permeability of a medium.
Photons are also the propagators of electromagnetic force - but in that role, they're virtual particles (whereas as radiation, they are not). Explaining virtual particles is however beyond the scope or necessity of this thread, so I'll leave that point there.

As the two fields are in phase (and indeed, responsible for one another), the net effect is that of an uncharged particle. And uncharged particles are not affected by magnetic or electric fields.

There are some cases of magneto-optic effects, but those are as a result of a gyromagnetic medium involved being altered by the presence of the magnetic field, and the effect that changed material then has on light - not a direct interaction of light and magnetics. And for the most part, I believe magneto-optic effects largely relate only to polarisation (the exception I know of is the Zeeman effect, which splits apart spectral lines into their components).

Evidently, I do actually know quite a lot when I actually have the time to think about it.

Lame Duck
15-02-2010, 11:32
Actually light ALWAYS travels at the same speed. It NEVER gets slowed down. What you may be confusing is that different wavelengths (colours basically) of light refrect (bend) different amounts when they pass through different materials. They actually still travel the same speed.

Making a laser longer would do nothing at all, except the fact that by making the weapon longer you have more area to add more magnets etc to accelerate the laser or energise it quicker. Therefore, you can make a more powerful laser, but using the same powerpack etc but with a longer distance between the mirrors etc there is no difference at all.

Glad to help. I'm always getting told everything I read is wasted cos I'll never need it! For the record, I work night shifts and spend them studying for pleasure. Anything and everything but usually history and science.

As pointed out, the only reason light refracts is due to changes in it's speed. This is why the speed of light being 3x10^8 is usuallly described as it's speed in a vaccum.

Making the laser longer was with regards to tolerances within the weapon in aligning the parts, and the practicalities of aiming the gun.

But, apart from that, very useful stuff!


its entirely possible that the longlas is a more intense laser than the las gun.
light intensity decreases the farther it travels through a medium and the more reflective particles in said medium. thats why the bottom of the sea isn't bright as day, why you see past your own nose when fog is thick enough, and why it isn't blinding whenever the suns up. now because the intensity decreases after going through a medium you're gonna have a certain kill range which is why a single guardsman with a lasgun can't take out orks from across a 5 foot gaming board. now if a longlas is a more intense laser then it has a greater range and penetrating power than a regular lasgun.
this just my thought on the matter.
i dont know light physics beyond basics if this was about mechanical physics i could probably have a better explanation

If you negate particle effects the only reason light intensity dereases over distance is due to attenuation. Lasers do not attenuate (at least conceptually).

catbarf
15-02-2010, 16:30
While it is odd that Abnett writes about laser weapons with such un-laser-like properties, he does take some creative liberties with traditional weapons as well.

I mean, in the OP's example of hearing a shot before being hit- real guns don't work that way. It's a well-known phenomenon that you feel the impact before hearing the shot.

Bunnahabhain
15-02-2010, 16:44
Depends on the weapon, catbarf.

A modern supersonic rifle round, of course.

Something very old and with a low muzzle velocity, say a muzzle loading blackpowder cannon, maybe not....

catbarf
15-02-2010, 17:17
Depends on the weapon, catbarf.

A modern supersonic rifle round, of course.

Something very old and with a low muzzle velocity, say a muzzle loading blackpowder cannon, maybe not....

True, but any modern automatic rifle has a muzzle velocity higher than the speed of sound. The M-16, for example, has a muzzle velocity of close to 1km/s, while the speed of sound is 340m/s.

Even the MP40, a WW2-era, stubby, pistol-round-firing cheaply-made mass-produced submachine gun has a muzzle velocity of close to 400m/s. It would be physically impossible to hear the shot before being hit.

Half the writing in 40k is rule of cool, and the other half is technobabble. Realism doesn't factor much into it, especially not when it comes to the exact operations of a laser weapon.

Fun fact, though- lasers could be useful for sniping since they produce no sound or flash, although the target would likely emit an explosion due to rapid vaporization. The primary issue is overcoming atmospheric attenuation.

Edit: Oh, and even many cannons from the 1800s had a muzzle velocity of above 400m/s. You've got to be talking about Civil War-era rifles or Napoleonic-era cannons to find weapons with muzzle velocities under the speed of sound.

MarcoSkoll
15-02-2010, 18:09
...has a muzzle velocity of close to 400m/s. It would be physically impossible to hear the shot before being hit.
A muzzle velocity of 400 m/s. Bullets, particularly pistol bullets, slow down quite fast, especially in that sort of velocity range.

Theoretically, if you're far enough away, the projectile can become subsonic again, and its own report could catch up with it. Although, that would admittedly be quite a long way away from the muzzle, and there wouldn't be a big time gap even then.

There are still quite a number of subsonic projectiles in the world. The obvious example is .45 ACP, with a muzzle velocity around 240 m/s (depending on the firearm in question).
Of course, the fact that it's then subsonic means that it has no sonic crack, and can be very effectively silenced. For example, the DeLisle Suppressed Carbine which fired the .45 ACP round was quieter firing than working the bolt action!


Edit: Oh, and even many cannons from the 1800s had a muzzle velocity of above 400m/s.
He may well be referring to hand cannons.
But let's just look at rifles - take the Martini-Henry rifle used at Rorke's Drift (1879), and even during some parts of the First World War. 270 m/s muzzle velocity.

Also, in response to the original point, when full of adrenaline, you may well not feel the hit until sometime afterwards. However, it is true to say that with almost all firearms, you would have been hit before you heard it.

catbarf
15-02-2010, 19:37
A muzzle velocity of 400 m/s. Bullets, particularly pistol bullets, slow down quite fast, especially in that sort of velocity range.

Theoretically, if you're far enough away, the projectile can become subsonic again, and its own report could catch up with it. Although, that would admittedly be quite a long way away from the muzzle, and there wouldn't be a big time gap even then.

Figured someone would point this out. Yes, it would slow down, and in theory from far enough away the deceleration would be enough to counteract the initial part of its flight (since even if the bullet slows down it will still take time for the sound wave to overtake it), then it may be heard before the impact. But with bullet drop and the distances involved, the chances of a hit are virtually nil and it's extremely unlikely to occur in any sort of intentional manner.

MarcoSkoll
15-02-2010, 20:51
But with bullet drop and the distances involved, the chances of a hit are virtually nil and it's extremely unlikely to occur in any sort of intentional manner.
Well, doing some quick maths, for a 400 m/s 9mm round, you can expect the distance where the bullet is overtaken by its own report to be about 200 metres away (with the bullet doing a little less than 300 m/s at the time).
Bullet drop will be about 1.5 to 1.8 metres.

An unlikely distance for a hit with an SMG admittedly, but not completely impossible - if you compensated for the range and got a lucky shot, it could happen.
So, it's at least reasonable for an initially (marginally) supersonic bullet to hit at the same time as the shot is heard. However, for it to be heard notably before (0.2 seconds) you're looking at about twice that distance.. Bullet drop is then in multiple metres. Hit probability: Exceptionally unlikely.

For the sake of interest, I looked at where a 5.56mm round would be overtaken by its report, and the answer is about 2400 metres away. You're not going to hear the report at those distances.

Apparently (and a little surprisingly) a 7.62mm round is only overtaken at 2600 metres - I thought it would be quite a bit more, but in the end, the lower muzzle velocity gives it less of a head start on the sound wave.

~~~~~

But, in the end, it's very unlikely you'll hear any shot before it hits you. The only probable exception is where the bullet was subsonic to begin with.

And of course, where light is involved... it would take light a second to reach you if you were three hundred thousand kilometres away. It would take the sound more than 10 days to get there.

Lame Duck
15-02-2010, 21:02
But, in the end, it's very unlikely you'll hear any shot before it hits you. The only probable exception is where the bullet was subsonic to begin with.

And of course, where light is involved... it would take light a second to reach you if you were three hundred thousand kilometres away. It would take the sound more than 10 days to get there.

You could assume a sound is produced a second before the shot is fired throught some sort of mechanism if you were getting desperate. (starter charge/process and a second crack due to gas expansion form the actual shot).

But then you'd really be grasping as straws.....

MarcoSkoll
15-02-2010, 22:51
But then you'd really be grasping as straws.....
You would.

Aside from the fact that effort is put into making guns as quiet as possible, if there was anything like a lock time that would make a notable difference to whether the sound was heard first, then they'd be pretty bad guns.

*Pull trigger*
*Target moves in the time it takes to start to fire*

Something like a springer air rifle has a time of about 8 ms from pulling the trigger to the pellet leaving the muzzle - and that's sloowwww in the firearms* world.
*Depending on how you define firearm. I, however, am including airguns within the definition.

Bunnahabhain
15-02-2010, 23:07
The obvious comparison is with cameras...

The shutter lag of compact digital cameras can be abysmal. How many people reading this have missed shots with them, due to the pause between pressing the button, and the camera working?

A digital SLR , on the other hand, doesn't suffer from this. Cheap ones have shutter lags of a few tens of milliseconds, pro ones reduce this considerably. If you know what you're doing, then you simply don't miss the shots due to the camera.

I'm asuming more people round here have used a variety of cameras, than badly designed fire arms

MarcoSkoll
15-02-2010, 23:26
The obvious comparison is with cameras...
Not to me! :D

You'll have to excuse that kind of thing. I spend quite a lot of time on forums with people who are very familiar with firearms, and sometimes that makes its way on to other forums.

... actually, you should see the weird comments I get when I make references to wargaming on their forums!

Hellebore
15-02-2010, 23:58
As pointed out, the only reason light refracts is due to changes in it's speed. This is why the speed of light being 3x10^8 is usuallly described as it's speed in a vaccum.

Making the laser longer was with regards to tolerances within the weapon in aligning the parts, and the practicalities of aiming the gun.

But, apart from that, very useful stuff!



If you negate particle effects the only reason light intensity dereases over distance is due to attenuation. Lasers do not attenuate (at least conceptually).

I assume you're talking about relative light speed? Relative to the observer? Because afaik light is always travelling at the same speed, the only reason it 'slows down' relative to the viewer is because matter absorbs it and reemits it which itself is not done at the speed of light. The slower the reemitance the slower the light appears to be travelling. But light itself doesn't change speed (it leaves the matter at the same speed it entered). That's afaik anyway.


As to hearing bullets before being hit by them, well the average nato 5.56mm round has a pretty high velocity:
http://en.wikipedia.org/wiki/5.56x45mm_NATO

Most current rounds are afaik supersonic rounds. Even a 9mm afaik travels faster than sound (~343 m/s):
http://en.wikipedia.org/wiki/Speed_of_sound
http://en.wikipedia.org/wiki/9x19mm_Parabellum
All but one of those 9mm parrabellum rounds travels faster than sound.

Hellebore

wilsongrahams
16-02-2010, 06:52
Just to mention, I was trying to describe both types of potential laser technology, one of which is really the plasma type.

Also, back to the speed of light thing, VERY RECENT research states that light never changes speed. This is explained by Einsteins SPECIAL Theory of Relativity (the later one). In actual truth, it is time that is altered locally, though I can't fully explain this myself because that is really hard to get your head round. Maybe we should leave this part of the discussion for now though as it's not really directly relevent and I know what you were trying to describe. I'll avoid being too technical in future.

MarcoSkoll
16-02-2010, 10:55
Also, back to the speed of light thing, VERY RECENT research states that light never changes speed.
We're not really talking about how it technically works if you look at it under quantum mechanics and special relativity.

The important thing to this discussion is how it appears to be from a macroscopic scale relative to an outside observer. And from that viewpoint, light does appear to have variable speed based on medium.
The fact that light may have a constant speed from its own perspective doesn't really matter to this discussion*.

*Nonetheless, something I admit I'm not completely clued up on - I shall have to rectify that. After all, science is interesting.

wilsongrahams
16-02-2010, 13:44
Yeah I'm sorry I went off on a tangent, but I did think I explained that it wasn't strictly relevent when I made the point...

Next topic should be melta weapons - hairdryer on steroids or microwave gun? lol.

SSG Snuffy
19-02-2010, 00:13
Figured someone would point this out. Yes, it would slow down, and in theory from far enough away the deceleration would be enough to counteract the initial part of its flight (since even if the bullet slows down it will still take time for the sound wave to overtake it), then it may be heard before the impact. But with bullet drop and the distances involved, the chances of a hit are virtually nil and it's extremely unlikely to occur in any sort of intentional manner.

Let's not forget the Whisper family of cartridges... they range from fairly small to quite large and all are designed to be subsonic. This allows them to be easily suppressed, and it means that the projectile will always arrive after the sound.

External ballistics can affected by the projectile's transition (deceleration) through the sound barrier. The Whisper cartridges are advertised on the premise that they are more accurate because they avoid the turbulence caused by transiting or approaching the speed of sound.

MarcoSkoll
19-02-2010, 13:02
This allows them to be easily suppressed, and it means that the projectile will always arrive after the sound.
Yes, but under those circumstances, whisper rounds can be suppressed effectively enough that the target will never hear the sound at all.

Saying "a subsonic bullet" will arrive after its sound doesn't really count when it was made subsonic in order that its sound could be eliminated.


The Whisper cartridges are advertised on the premise that they are more accurate because they avoid the turbulence caused by transiting or approaching the speed of sound.
That's... rather stretching the truth.

Most rifle bullets are still considerably supersonic when they hit, so they won't have suffered from any transonic stability issues.
The distance it would take the average supersonic spitzer bullet to become a sufficiently low velocity as to be affected by transonics is well in excess of the range that a Whisper round can actually feasibly make it out to at all.

Additionally, subsonic bullets will suffer more heavily as a result of gravity, wind, Coriolis effect (although not notably) and target movement, making far more work for the shooter in order to actually make the hit.
Theoretically, they can group better (lack of any sonic shockwave at all helps), but grouping is a measure of repeatability, not accuracy.
Accuracy is hitting what you wanted to - not hitting the same place several times.

Yes, you could argue greater repeatability under a given set of stable conditions and thus better precision, but when you throw in variable conditions, a supersonic projectile will almost certainly win out.

SSG Snuffy
20-02-2010, 00:10
That's... rather stretching the truth.


Not too put too fine a point on it, but I didn't say that I suscribed to their theory - merely that they advertise it that way.

I agree with you that at most engagement distances the Whisper bullets' nice BC won't be enough to make up for longer flight time and correspondingly greater drop. I was just playing the devil's advocate with catbarf's response to one of your posts.

Sygerrik
20-02-2010, 01:05
Las weapons aren't really Light Amplification Stimulated by Emission of Radiation. They're little dense packets of energy that travel really fast. They're not shooting photons.

Iverald
20-02-2010, 01:29
Next topic should be melta weapons - hairdryer on steroids or microwave gun? lol.

Y'know, I've half a mind to star one. Not that I have any competence in physics... :p

MarcoSkoll
20-02-2010, 02:07
Not too put too fine a point on it, but I didn't say that I suscribed to their theory.
And at no point did I say that you necessarily did subscribe to it. I was merely pointing out (for the benefit of all the thread's readers) that the marketing claims are only true if you take a very specific set of circumstances.

Not only is the marketing deceptive, it can give people the wrong idea. I actually reckon that a notable portion of the really whacked-out science people come up with is as a result of something they learnt from weasel worded marketing. More again from dodgy science in TV shows or films...

... but most of it because a lot of people are just idiots who don't care. While I'm a natural sceptic and well enough educated to be able to spot the nonsense a mile off, I'm told that the science knowledge of the average UK citizen is equivalent to an F at GCSE level.


Las weapons aren't really Light Amplification Stimulated by Emission of Radiation.
Congratulations, you're the newest recipient of the "Didn't read the whole thread before posting" award.


Y'know, I've half a mind to start [a meltagun thread].
Please don't. I'll only get roped into that one as well, and I'm supposed to be working on my models, not having internet arguments...

DapperAnarchist
20-02-2010, 03:50
I'm suprised that people are surprised that Dan Abnett made a mistake... I mean, his books are full of them. From the basic fluff mistakes (Commissars do not command regiments!) to physics slip ups (lots of stuff from this thread) to the bizarre (hey! Naval Armsmen in a skimmer! I know, I'll shoot them down WITH A NEEDLE RIFLE. Not the Armsmen, the Skimmer. Yeah. My Needle Rifle fires explosive needles. No, I don't know how much explosive you can actually fit in a needle)...

His books work due to mood, plot, and character, not accuracy to fluff or physics.

Also - But Marco, you're so good at them! :D (note - this is teasing, not trolling)

Kensai
21-02-2010, 06:44
In essence, the op is correct.

Ballistic trajectories on modern weaponry are affected by a myriad of factors including but not limited to distance to target, wind speed and direction, humidity, declination angle to target, and at extreme distances the Coriolis effect.

In theory, a laser would have no mass, and therefore would be unaffected by the above factors. The speed of light/speed of sound issue would be irrelevant, as a laser rifle presumably does not emit any classic gun sounds due to its lack of a primer or powder to ignite.

On the other hand, this book was written as part of the 40k universe, and nobody wants to take the time to try and quantify every impossibility which occurs there.