PDA

View Full Version : Imperial Spaceship mounted weaponry?



Raellos
09-07-2010, 14:50
Just wondering what the different types of weapons mounted on Imperial (Naval, Mechanicus and other) are.

I was reading about USS New Jersey providing artillery support in Korea and Vietnam, and I thought that a grounded Naval vessel could do something similar. I thought I'd keep that in my memory banks until I can run my anal-retentive campaign (if ever), with a grounded frigate on one of the outlying worlds providing hard defences and artillery support for the ground sloggers.

Might even make for an interesting run up game for an Apocalypse game, if I ever become as mad as Old Guard or Digits.

Iracundus
09-07-2010, 14:56
Your best reference would be BFG. Weapon batteries consist of a wide variety of weapons but the bulk of Imperal weapons are suggested to be either projectile weapons or plasma (See BFG rulebook references to the Tyrant class and Murder clsas cruisers). However this can vary. For example, Sword frigates are described as having a high readiness rates for their laser weapons, and the Firestorm frigate (derived from the Sword) is described as having a forward lance weapon system due to re-routing some power from the lasers.

Stomer70
09-07-2010, 14:58
I don't think the IN ships could ground themselves and then take off again. I am quite sure they are only capable of space flight and not atmospheric flight. However you could use them as an orbital bombardment?

And the guns (from Soul Drinkers) on the ships are mangalasers and macro cannons. Not sure what they shoot or do though...

Iracundus
09-07-2010, 15:05
Escort sized ships can land but not capital ships.


Escorts and transports which voluntarily move off the planet edge are said to have landed and are removed from play; capital ships cannot land. -p.48, BFG rulebook

IvanTih
09-07-2010, 15:45
Imperial weaponry is quite versatile for instance weapon batteries can be armed with mass drivers(something like railgun),graviton guns,plasma projectors,macro cannons and lasers.

Sai-Lauren
09-07-2010, 16:09
Imperial weaponry is quite versatile for instance weapon batteries can be armed with mass drivers(something like railgun),graviton guns,plasma projectors,macro cannons and lasers.

Railguns are Tau, and graviton guns left with the Squats. ;)

Laser weapons are limited to the horizon, projectile weapons are limited by atmosphere and gravity - that said, they're still lobbing things well over the horizon (the 6" guns in the forward turrets of HMS Belfast are aimed at Scratchwood services - a mere 12.5 miles away, whilst the Yamato's 18.1" main guns could get out to 26 miles).

And whilst it would be a useful strongpoint, magazine etc, I can't see the Navy being too happy about one of their vessels staying dirtside for too long.

Plus, if it's grounded, it can only hit things in range, wheras if it's orbit, then it can potentially hit anywhere on the planet, although it'll have to wait until in range, or expend fuel to change it's orbit to attack it quicker.

Decius
09-07-2010, 16:27
The Rogue Trader RPG system lists several different weapon types for ships. Thought the book's adhearance to cannon is disputed by some, it's good enough for me. :p
Let's see here...

"Macrobatteries are ranks of massive cannons or other weapons, fired in volley to overwhelm an enemy in a barrage of destruction" -RT pg 202
The most common macrobatteries seem to be macrocannons, of which the book lists several grades. Naturally, Mars pattern macrocannons are the best. It's also worth noting that a broadside of macrocannons is more than just the gray squares on this green retribution class battleship (http://fc09.deviantart.com/fs30/f/2008/098/9/c/Battlefleet_Gothic_Scale_Chart_by_The_First_Magelo rd.png). Those are just the largest cannons, probably surrounded by many smaller macrocannons. The book also list laser batteries, with superior range, and plasma batteries, with superior damage. These are superior macrobatteries but also more expensive and harder to maintain (one can assume at least).

"Lances are the rapier to the macrobatteries' hammer. They are a single beem of energy buring through their enemy's armour and deep into its vitals."
RT pg 203

In the above link, those turrets on top of the battleship are lances. The main advantage lances have over weapon batteries, reflected in their rules from both Battlefleet Gothic and Rogue Trader, is that the target's armour is irrelevant.

Those are just the two basic types of weapons. There are also nova cannons, torpedoes (of many flavours), attack craft (also mant flavours), defense turrets, and then multiply that by all the xeno variants too (which might be found on a rogue trader's ship).

Take a look at the rules for Battlefleet Gothic for free here (http://www.games-workshop.com/gws/content/article.jsp?aId=4300022) or here (http://battlefleet-gothic.wikia.com/wiki/Battlefleet_Gothic_%28Rules%29). Even if you aren't familar with the rules there's plenty of fluff to answer your questions.

Iracundus
09-07-2010, 16:43
The most common macrobatteries seem to be macrocannons, of which the book lists several grades.


This point is disputable given some BFG background, which suggests plasma cannons are the most common batteries. The Tyrant class cruiser's longer ranged weapon batteries are attributed to be from "superfired" plasma weapon technology rediscovered by the AdMech. The Murder class cruiser, before being replaced by the Lunar class, was described as having several decks of some of the best plasma batteries ever produced by the Adeptus Mechanicus. The Murder class only has weapon batteries as its main armament, which is suggestive that these plasma weapons are the bulk of the weapons if they are so worthy of being mentioend.

Decius
09-07-2010, 16:51
Apart from the Tyrant class, which as you say has rediscovered plasma technology, and the Murder class, which is no longer a common Imperial vessel, are there any other ships that, by cannon, have plasma batteries as standard?

Iracundus
09-07-2010, 17:03
Apart from the Tyrant class, which as you say has rediscovered plasma technology, and the Murder class, which is no longer a common Imperial vessel, are there any other ships that, by cannon, have plasma batteries as standard?

The Murder class formed the backbone of Battlefleet Obscuras before the Lunar class. They were not just some niche class. The Tyrant class is also not described as an incredibly rare class.

If Murder class cruisers were common, it means also that plasma weapons as the mainstay of ship weaponry were also common. The Murder class is also very similar to the heavier Hades heavy cruiser class which is a Murder class in every respect except with the addition of some dorsal lance turrets.

Decius
09-07-2010, 17:46
I guess I can see you point. If the Murder class was common, and it had plasma batteries, then plasma batteries must have also been common. I can see the logic.

Still, murder class cruisers were common, but are not anymore. Does this also mean that plasma batteries are also less common as a result? I know that Imperial Naval doctrine has changed, and that the Murder class has less of a place in that doctrine than the Lunar class, but could the difficulty in producing plasma batteries have also had a hand in the switch over?

You do make a good point on the Tyrant class though. It has plasma betteries and isn't exactly a rare ship class. The Lunar is likely more common simply because it is a more flexible vessel. Then again, isn't the Lunar renowned for being the simplest to construct? Couldn't macrocannon batteries, as opposed to plasma batteries, have a hand in that?

Plasma batteries are probably more common than I give them credit for, especially in the Imperial Navy where they won't exactly want to "get 'em cheap". However, you must admit that you haven't given direct evidence to support the claim that plasma batteries are the mainstay weaponry of Imperial ships, merely evidence that would imply such. Not that I doubt you but... well actually I do doubt you. BUT I am willing to be proven wrong. :p

flota
09-07-2010, 18:04
nova cannons are somekind of "rail or graviton" weapon right?

macrocannons seems to be the most common weapon the IN has to offer.
i thought plasma was a rare weapond in ship to ship combat...

Iracundus
09-07-2010, 18:31
Still, murder class cruisers were common, but are not anymore. Does this also mean that plasma batteries are also less common as a result? I know that Imperial Naval doctrine has changed, and that the Murder class has less of a place in that doctrine than the Lunar class, but could the difficulty in producing plasma batteries have also had a hand in the switch over?

You are presupposing that it was an issue with plasma batteries rather than other issues leading to a doctrinal switch. The issues with the Repulsive class and the other grand cruisers, or the difficulty with the Overlord class battlecruiser suggest it may be as much about engines and power systems as just weaponry.

Although the Murder class is notable for having some of the "best" plasma batteries produced by the AdMech, this doesn't mean they have become rare, just that the others may not be up to the same quality. This is reflected in the stats, in which the Murder class outranges the Lunar.



You do make a good point on the Tyrant class though. It has plasma betteries and isn't exactly a rare ship class. The Lunar is likely more common simply because it is a more flexible vessel. Then again, isn't the Lunar renowned for being the simplest to construct? Couldn't macrocannon batteries, as opposed to plasma batteries, have a hand in that?

Once again simplicity of construction may not be entirely due to weapons. In particular the Lunar has lance turrets, which are higher tech and if anything the Imperium also has trouble replicating these at the same levels of performance as before. One only needs to look at older Imperial battleship designs like the Desolator and the Apocalypse for how lance performance has changed. Nonetheless they are still used even if of lesser quality. There isn't a shift as dramatic as shifting weapon type entirely.

The 2 weapon battery sections on a Tyrant are identical to gross visual apperance to each other and also to a Lunar class's weapon batteries. The superfired plasma batteries are described as being almost able to deliver the same weight of fire at close quarters than comparable cruiser weapon decks. Thus if the difference between a Tyrant and Lunar really is just the addition of that second battery section, and that battery section is primarily plasma weaponry but which otherwise looks identical to the other existing section, then it suggests the first section is also primarily plasma weaponry.

By primarily, I am referring to the main square weapon ports, not any secondary weapon systems represented either by the nubs above and below or simply abstracted into the ship's Turret value. The depiction of the Emperor class battleship Divine Right in the BFG rulebook certainly shows a profusion of other weapon systems that may well be projectile weapons.

The size of the square primary weapon ports suggests it is also unlikely to be projectile weaponry given how ships are describing as firing many salvoes and volleys, whereas if the shell sizes were truly matching the size of those square ports, a cruiser would not be able to carry many shots at all. If the shots are not the size of that port, then it raises the question of why, which then requires further convoluted explanation rendering it the less parsimonious explanation by Occam's Razor.

One additional detail suggests these weapon ports can be ruled out as lasers. The Sword and Firestorm class frigates are both described as having laser based weapon batteries, and have distinctive circular weapon ports. The Firestorm channels half of the power from these batteries into a forward lance and has correspondingly half as many of those round laser ports. These ports are quite different from the blockish appearance of the main weapon batteries on all Imperial capital ships.

IvanTih
09-07-2010, 19:45
Railguns are Tau, and graviton guns left with the Squats. ;)

Laser weapons are limited to the horizon, projectile weapons are limited by atmosphere and gravity - that said, they're still lobbing things well over the horizon (the 6" guns in the forward turrets of HMS Belfast are aimed at Scratchwood services - a mere 12.5 miles away, whilst the Yamato's 18.1" main guns could get out to 26 miles).

And whilst it would be a useful strongpoint, magazine etc, I can't see the Navy being too happy about one of their vessels staying dirtside for too long.

Plus, if it's grounded, it can only hit things in range, wheras if it's orbit, then it can potentially hit anywhere on the planet, although it'll have to wait until in range, or expend fuel to change it's orbit to attack it quicker.
My info is from BFG rulebook.

Decius
09-07-2010, 20:00
You are presupposing that it was an issue with plasma batteries rather than other issues leading to a doctrinal switch.

I wouldn't say presupposing. Merely providing a counter point. I'm aware that weaponry alone didn't force the doctrinal switch, but, since Imperial technology is know to have periods of decline, it may have been a factor. At least a factor in the discontinuation of the Murder class.

I must admit, you have many excellent and compelling points. However, I was looking for something more conclusive, like a quote and a page number, rather than what can be inferred from pictures and models.

Your analysis regarding the "square weapon ports", though well thought out, is based on imperfect information. The pictures and models lack the details necessary to conclusively show what exactly those square weapon ports are. It may not be a weapon at all, but rather a standardized armoured housing to protect whatever weapon has been installed on the ship, be it a single plasma cannon, a trio of macro lasers, or a cluster of macrocannons arranged as a gatling gun of sorts. If those squares are simply an armoured housing, that would explain why Imperial cruisers all have identical looking broadsides while some are said to have different or unique weapon systems.

All of the above is pure speculation on my part. But, in all honesty, is it any less valid than your own?

*Somewhat unrelated, but I always found it curious that most Chaos ships are said to be former Imperial ships, yet the ship classes have names like Repulsive, Carnage, and Murder. Are these new code names for the ships, or did a younger Imperium beleive "Repulsive" was a fitting name for a ship of the Emperor's navy?

Iracundus
09-07-2010, 23:28
I wouldn't say presupposing. Merely providing a counter point. I'm aware that weaponry alone didn't force the doctrinal switch, but, since Imperial technology is know to have periods of decline, it may have been a factor. At least a factor in the discontinuation of the Murder class.

Actually we know nothing of why the Murder class was discontinued. The only mentions are that it was formerly the mainstay of Battlefleet Obscuras but that also a large number turned renegade.

In BFG Armada for example, it mentions how certain classes are disfavored if large numbers of that class turn renegade, and the belief that perhaps some flaw in the design or architecture of the ship renders it susceptible to disloyalty and dark influences.



*Somewhat unrelated, but I always found it curious that most Chaos ships are said to be former Imperial ships, yet the ship classes have names like Repulsive, Carnage, and Murder. Are these new code names for the ships, or did a younger Imperium beleive "Repulsive" was a fitting name for a ship of the Emperor's navy?

Why not? The Imperium is a brutal police state valuing power and order and intolerance.

Decius
09-07-2010, 23:46
Why not? The Imperium is a brutal police state valuing power and order and intolerance.

Yeah, I can see that for the Murder or the Carnage. But, the Repulsive? :p

Havock
10-07-2010, 02:04
nova cannons are somekind of "rail or graviton" weapon right?

macrocannons seems to be the most common weapon the IN has to offer.
i thought plasma was a rare weapond in ship to ship combat...

Nova cannons work on the same principle as a railgun, albeit drive-assisted so it seems. Looking at the model it is more likely a coilgun though.

The Imperium likely knows how to make a railgun, as the fundamental principles are very easy really, it's jsut that they don't bother building it any smaller than skyscraper-launching extinction level-impact weaponry ;)

It's alsonot mounted on anything smaller than cruisers (lord Daros and somethingsomething Lunarclass cruisers) so utterly irrelevant to the topic. A nova cannon impact would be akin to "rock falls, everybody dies".

Yes, also in games of apocalypse.


Yeah, I can see that for the Murder or the Carnage. But, the Repulsive? :p

Could be that it initally was known as the "Repulse" class Grand Cruiser, only after their demise in the Imperial Arsenal and their proliferation among Chaos Fleets their name was changed to Repulsive. Could be the Impies showing disgust, could be the Chaos people showing their disgust ;)

Iracundus
10-07-2010, 07:02
The Imperium likely knows how to make a railgun, as the fundamental principles are very easy really, it's jsut that they don't bother building it any smaller than skyscraper-launching extinction level-impact weaponry ;)

It's alsonot mounted on anything smaller than cruisers (lord Daros and somethingsomething Lunarclass cruisers) so utterly irrelevant to the topic. A nova cannon impact would be akin to "rock falls, everybody dies".


Nova cannons are not extinction level weaponry. Their level of devastation has been discussed before in past background threads, and that level of power is not consistent with their described performance in both background and rules. For example, short of a critical hit, even an unshielded 3km long cruiser can survive a direct nova cannon hit, and shielded escorts can survive being in the blast radius.

cornonthecob
10-07-2010, 07:45
Nova cannons are not extinction level weaponry. Their level of devastation has been discussed before in past background threads, and that level of power is not consistent with their described performance in both background and rules. For example, short of a critical hit, even an unshielded 3km long cruiser can survive a direct nova cannon hit, and shielded escorts can survive being in the blast radius.

It shoots you with a black hole. I'd say that's pretty damn devastating.

RCgothic
10-07-2010, 08:17
I don't think it implies that. It causes an 'Implosion'. A spacetime implosion might be a black hole, but it's far more likely to be a warp implosion, which isn't.

Lord Zarkov
10-07-2010, 18:51
Nova cannons are not extinction level weaponry. Their level of devastation has been discussed before in past background threads, and that level of power is not consistent with their described performance in both background and rules. For example, short of a critical hit, even an unshielded 3km long cruiser can survive a direct nova cannon hit, and shielded escorts can survive being in the blast radius.

An unshielded 3km cruiser will survive a direct hit most of the time yes, but unshielded 1km long escorts will all die even if just hit by the blast. Given that the blast is larger than a moon, everything on a 40K (or even epic) battlefield is going to die, with the possible exception of really heavily shielded Titans - yes it may not be extinction level, but one shot's still going to wipe out whatever it hits over a massive area.

Post
11-07-2010, 10:25
'Hellforged' and 'Cadian Blood' describe Novacannons firing a warhead at 2/3 the speed of light that implodes to form a singularity inside the ship that lasts a few seconds before disappearing. Typhus's ship survived two hits and a Necron ship basically laughed at it, guess spaceships are just that tough.

RCgothic
11-07-2010, 10:46
The shell must utilise a low-level warp field then, because at 0.67C through normal space, the shell would happily obliterate a 3km vessel without requiring a warhead.

azimaith
11-07-2010, 10:50
40k space combat is so incredibly far from current laws of physics its not really even worth attempting to explain it. Firing practically anything you could hold, much less something the size of a sky scraper at .75c is going to kill anything and everything in its path. It wouldn't even matter how thick the armor would be. Space combat is a giant ridiculous mess. If something can survive being hit by fragments of that .75c object they're hardly going to have to need escorts. Last time I had this debate I think the impact of a nova cannon was something akin to being hit with the moon traveling at 10FPS. Ships that could shrug off nova cannons could park in the middle of suns and drive through planets they'd be so tough. Space Combat would be a non-affair unless you either could fire things at .75C or could fire planets at each other.

There is basically 0 sense in 40k Space Combat whatsoever.

KE of being hit by a 1 Kg object at .75c
25,277,489,401,972,996 Joules

Joules in a nuclear blast of one megaton (A million tons of TNT)
4,180,000,000,000,000

That means that 1Kg object at .75c is about
6.0472462684145923444976076555024 megatons on impact. 6 megatons. 6 million tons of TNT.

That's from an object that's like 2.2 pounds. Anything surviving that could be detonating kiloton nukes as Christmas lights on their hull. Why would they even fear boarding craft, just use explosive reactive nuclear bomb armor.

Iracundus
11-07-2010, 11:05
'Hellforged' and 'Cadian Blood' describe Novacannons firing a warhead at 2/3 the speed of light that implodes to form a singularity inside the ship that lasts a few seconds before disappearing. Typhus's ship survived two hits and a Necron ship basically laughed at it, guess spaceships are just that tough.

Warriors of Ultramar describing part of the battle for Tarsis Ultra (which appears in the Tyranid Codex and is thus canon), describes a nova cannon shell as moving at 5,000 km per second which is 18,000,000 km per hour. That was for a shot at a target roughly 125,000 km away, or a good portion of a nova cannon's range.

That is far less than 2/3 lightspeed. It is 0.016C.

Post
11-07-2010, 11:11
Hmm, Speed of light is 1,070,000,000 km/h, that's less than 10%. Still pretty fast. and you then have the black hole. Did the description say 'singularity'?

Iracundus
11-07-2010, 11:14
No because the nova cannon was described as firing shells that destroyed the target via a giant explosion, possibly plasma based. Nowhere were "black holes" nor singularities described whatsoever.

Lord Zarkov
11-07-2010, 12:19
Also given the scales involved a 'direct hit' from BFG still wouldn't involve being hit by the shell itself - the 'direct hit' radius is about 1cm which is what, 10,000km IRL?

Given that the shell is skyscraper sized this implies that what qualifies as a 'direct hit' is actually more of a 'near' miss - which seems sensible, given the rediculousness of actually hitting a ship directly (let alone multiple) given the ranges involved (and 3D effects etc as well).

Iracundus
11-07-2010, 12:35
Andy Chambers has stated it is 1cm = 1000 km

Lord Zarkov
11-07-2010, 12:44
Cheers, I knew there was an exact quote somewhere, but couldn't seem to find it.

1000km for a 'direct hit' then - still many orders of magnitude larger than the warhead.

Post
11-07-2010, 14:31
No because the nova cannon was described as firing shells that destroyed the target via a giant explosion, possibly plasma based. Nowhere were "black holes" nor singularities described whatsoever.

Conflicting fluff, Cadian blood and Hellforged both states that a Nova warhead 'implodes' causing sections of the ship to 'simply cease to exist'.

Raellos
11-07-2010, 14:32
Currently I'm thinking a pinnace in low orbit at an unimportant world on the fringes of the campaign might be just as interesting, but the first idea is still just as valid both in game terms and as an interesting exercise.

Are large scale Imperial electromagnetic rail or coil weapons common?


Laser weapons are limited to the horizon, projectile weapons are limited by atmosphere and gravity - that said, they're still lobbing things well over the horizon (the 6" guns in the forward turrets of HMS Belfast are aimed at Scratchwood services - a mere 12.5 miles away, whilst the Yamato's 18.1" main guns could get out to 26 miles).

And whilst it would be a useful strongpoint, magazine etc, I can't see the Navy being too happy about one of their vessels staying dirtside for too long.

Plus, if it's grounded, it can only hit things in range, wheras if it's orbit, then it can potentially hit anywhere on the planet, although it'll have to wait until in range, or expend fuel to change it's orbit to attack it quicker.

The article lists the range of New Jersey's 16" guns as 30 miles.

I meant that it was grounded for repairs, not grounded by choice. Not clear, I know!

Also, Repulsive seems just about the most Imperial name of the Chaos classes. The root word being Repulse, the 'disgusting' definition being something of a corruption.

AndrewGPaul
11-07-2010, 18:02
Railguns are Tau, and graviton guns left with the Squats. ;)



Each battery consists of rank upon rank of weapons: plasma projectors, laser cannons, missile launchers, rail guns, fusion beamers and graviton pulsars. (emphasis mine).

Lord Damocles
11-07-2010, 19:05
Conflicting fluff, Cadian blood and Hellforged both states that a Nova warhead 'implodes' causing sections of the ship to 'simply cease to exist'.
Have you got a page reference? I can't find any reference to Nova Cannon warheads 'imploding' or anything similar in Hellforged (not when the Constant fires on the Brokenback (pgs.42-3), or when she fires on the Necron cruiser during the first battle with the explorator fleet (pg.84), nor when she fires her last Nova shot before falling to the mother ship (pg..282)).
In fact when the Constant hits the Necron cruiser, the Nova shell is actually described as exploding: 'The shot slammed into the upper hull of the crescent ship. The energy of the blast flashed so bright the craft was like a second sun, the nova cannon's power discharging in every direction at once' (Hellforged, pg.84).

RCgothic
11-07-2010, 19:18
BFG rulebook, p22: "The projectile implodes after a preset distance."

FrankieKhainor
11-07-2010, 19:36
From the horus heresy novels, most of the ships seem to have lances on the sides and a really big one on the front. Well, it's an obvious set up. They'll probably have thousands of little volcano cannons and stuff for dealing with small craft - eg. manta! I'm guessing tau ships would have massive railguns, and eldar humungous amounts of prism cannons all focussed into one huge beam.

TrooperTino
11-07-2010, 21:25
one sequence in the game Firewarrior gives a good impression what a firework an imperial broadside is. it may have flaws, like all laser/energy beam weapons are in red, and it looks like all weapons fired are about the same size. no REALY big macrocannons that stand out in the fired broadside, but can be that these bigger bangs are not used because the imperials don't want to destroy the tau ship. But it looks like there are many different weaponsystems in use at the same time.

I think of broadside that way: Because a ship is classified as using macrocannons doesn't mean there are no plasmacannons or other more esoteric weapons, just that macrocannon-class are the most used on that ship and that the biggest are macrocannons.


found the vid on youtube... had in a bit different in mind ;)

http://www.youtube.com/watch?v=VonES_h15DM

Sai-Lauren
12-07-2010, 08:49
'Hellforged' and 'Cadian Blood' describe Novacannons firing a warhead at 2/3 the speed of light that implodes to form a singularity inside the ship that lasts a few seconds before disappearing. Typhus's ship survived two hits and a Necron ship basically laughed at it, guess spaceships are just that tough.

One of the alternate nova cannon rounds in BFG Magazine was a singularity warhead, which implies that the rest aren't. ;)

Also, the original description in RT for Crack grenades and missiles was that they were implosion munitions.

A Nova Cannon could potentially be a supergun - basically a gun barrel with multiple firing chambers that fire in a controlled sequence to accelerate the munition to high speeds.



Andy Chambers has stated it is 1cm = 1000 km

I thought it was effectively a sliding scale like time in the game - the closer the vessels got, the shorter time and distances were.



Originally Posted by Andy Chambers, on page 20 of Battlefleet Gothic
Each battery consists of rank upon rank of weapons: plasma projectors, laser cannons, missile launchers, rail guns, fusion beamers and graviton pulsars.

Ok, sorry. :)

However, to my knowledge, this is the only mention of railguns in Imperial Technology.

AndrewGPaul
12-07-2010, 16:57
I took it to mean that Imperial railguns, or other electromagnetic accelerators, worked no differently to conventional chemical firearms - perhaps there are boltgun variants using railgun technology to launch the bolts, rather than an initial chemical propellant. Older material mentions Imperial shuriken catapults, cruder than the Eldar designs, using a combination of magnetic and gravitational acceleration.