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 sierra 1247 wrote:
Anyway back on topic, as bolter rounds utilise rocket propellants (dont ask me how the recoil isnt as bad as it should be cause i dont have a clue)

Way back when, the original fluff, especially that written by Ian Watson, describes the bolter round having an initial boost phase, ejecting the round from the bolter before the main rocket chrage ignites,hence the bolter having little or no recoil and the bolt round being caseless. Of course, this wasn't condidered epic enough and got out-fluffed. Pity really, as Mr Watson's depiction of Space Marines was far darker and more adult than some of the tosh being trotted out these days.

They do, in fact, explode in the space marine game, but not like a grenade size explosion, more like an explosion the size of a small football, and they tend to explode internally. This is why you get such a bloodsplatter when you shoot an ork in the game, it's literally being expelled out of them as the round blows up inside their chest.

Orks, being orks, are incredibly resillient, and can fight on for a good while even if all their organ's rupture.

But shoot a grot with that gun, and they do practically explode. And it is hilariously good fun xD

Yes, that's what I said-- not a fragmentation explosion, more like a big pop.

 Melissia wrote:
20mm rounds are still much thicker than .75 caliber rounds.

.75 caliber is 19.05mm. An interesting definition of "much".

In the fire warrior PS2 game they explode

 Veteran Sergeant wrote:

 Melissia wrote:
20mm rounds are still much thicker than .75 caliber rounds.

.75 caliber is 19.05mm. An interesting definition of "much".

In terms of bullet thickness, that's a rather important difference.

 Satan's Little Helper wrote:
In the fire warrior PS2 game they explode

Should we crucify this one?


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 Melissia wrote:

 Veteran Sergeant wrote:

 Melissia wrote:
20mm rounds are still much thicker than .75 caliber rounds.

.75 caliber is 19.05mm. An interesting definition of "much".

In terms of bullet thickness, that's a rather important difference.

She has a point. a 10mm round is significantly more powerful than a 9mm

Betrayel puts pre heresy bolters at .70 caliber, other bolters at .65, bolt pistols at .50 cal, just adding more info to the discussion

 Formosa wrote:
Betrayel puts pre heresy bolters at .70 caliber, other bolters at .65, bolt pistols at .50 cal, just adding more info to the discussion

Good sir, you've just added dysentery to a gak storm. I commend you.

Tethgar wrote:She has a point. a 10mm round is significantly more powerful than a 9mm

I love when people have no functional knowledge of firearms and ammunition try to comment on them.

Not aside from the fact that between 10mm and 9mm, 1mm is an 11% increase in size as opposed to where with 20mm to 19mm it's only 5%, there are a lot of things that go into the power of a round, not simply size. 10x25mm's casing is also much longer than 9x19mm's which means it carries more propellant. The power differential of the 10mm Auto round vs 9mm Parabellum has only a small amount to do with the width of the projectile. Certainly .357 Magnum (9x33mm) is equitable in power to 10mmA even though it gives up a whole millimeter.

So no, just under 5% is not "much thicker" and no, it's not a "rather important difference" when it comes to bullet thickness and ammunition in general. If she said that 10mm Auto is "much thicker" than .22WMR (5.6x27mm), then it's a different story. We're not talking about 5% of a significant measurement here like the crust of the Earth is 5% thicker in one place as opposed to another.

Let's try to have everyone stick to their realms of knowledge. For some of you, ammunition may not be one of them.

I never said it was significantly more powerful. I said it was significant, period.

Also, to toy with a tangent, the area of a 9mm circle is actually closer to 19% less than a 10mm circle, while the area of a 19mm circle is closer to 9.8% of a 20mm circle. Math is funny like that.

Well, geometry anyway...

Bullet caliber isn't everything.


on the left you have a .22 LR and on the right a .223 Remington

now caliber is the diameter of a bullet in inches - that means that the .223 is 3 thousandths of an inch wider than the .22.

Now guess which one will do more damage.

Now about the vulcan mega bolter...

I am not an expert on weapons or ammo, but to me the bolter round sounds definitely not like a bullet, but a crossover between this:

japanese ww2 grenade launcher

and this:

U.S. "Bazooka" missile launcher

Because of the detonation round and the hybrid two step propulsion system a bolter qualifies somewhere between grenade gun and missile launcher.

So whatever some authors have to say about caliber in numbers, the massive look of the models does it justice.

It's not "whatever authors say". It's a long-established convention that it is a .75 caliber weapon for boltguns and bolt pistols, and a 1.00 caliber weapon for heavy bolters. The authors that deviate from this are the exception, not the rule.

As such, while I can believe that there ARE boltguns of differing caliber, these are by no means normal or standard.

 Hruotland wrote:
I am not an expert on weapons or ammo, but to me the bolter round sounds definitely not like a bullet, but a crossover between this:

japanese ww2 grenade launcher

and this:

U.S. "Bazooka" missile launcher

Because of the detonation round and the hybrid two step propulsion system a bolter qualifies somewhere between grenade gun and missile launcher.

So whatever some authors have to say about caliber in numbers, the massive look of the models does it justice.

Ever heard of the Gyro-Jet?

Imagine a bolter in .45 with no explosion.

Boltguns are not gyrojet weapons. Gyrojet weapons are one-stage, while boltguns are two-stage.

 Melissia wrote:
Boltguns are not gyrojet weapons. Gyrojet weapons are one-stage, while boltguns are two-stage.

Correct me if I'm wrong but a kick charge of sorts propels it out of the barrel and then the rocket engine kicks in correct?

Tethgar wrote:

 Melissia wrote:
Boltguns are not gyrojet weapons. Gyrojet weapons are one-stage, while boltguns are two-stage.

Correct me if I'm wrong but a kick charge of sorts propels it out of the barrel and then the rocket engine kicks in correct?

It's closer to a normal bullet that has rocket engine propelling it afterwards for greater accuracy at range.

The bolt pistol is perfectly capable of penetrating armor at close range. Gyrogets could be stopped by putting your finger on the end of the barrel, in comparison.

 Melissia wrote:

Tethgar wrote:

 Melissia wrote:
Boltguns are not gyrojet weapons. Gyrojet weapons are one-stage, while boltguns are two-stage.

Correct me if I'm wrong but a kick charge of sorts propels it out of the barrel and then the rocket engine kicks in correct?

It's closer to a normal bullet that has rocket engine propelling it afterwards for greater accuracy at range.

The bolt pistol is perfectly capable of penetrating armor at close range. Gyrogets could be stopped by putting your finger on the end of the barrel, in comparison.

I'm reinforcing your argument.

Never heard before of the Gyrojet, but what I read in wikipedia, it sounds like a major inspiration source for the Boltgun for me. Expecially the part about low velocity leaving the barrel. If you really can stop a gyrojet projectile by closing the barrel with your finger, then this surely has led to the introduction of the two-stage propellant system in the fluff.

Now then... the thing with the finger in the barrel... I heard that about blackpowder weapons of the old, including 19th century revolvers. Making the weapon explode in the shooter's face instead of just de-fingering the target before eating his brain. Do you have evidence for this not being just another citation of a quite silly trope?

Also how I understand my physics, then the projectile gets it's target deforming energy from the kinetic energy it gains. In other words, if a projectile, ballistic or self-propelled, has gained a certain velocity in the moment of the impact, then it has gained the same power to penetrate it's target. If the projecitle is a self-propelled one with still propellant left, then it even has more, because it is still accellerating. I.e. in the act of deforming the target there is still an amount of kinetic energy added.

Plus the bolter is described to have a detonator.

So even if the gyrojet is a weaker weapon in comparison to standard firearms, (and it is because of precision issues, or so wikipedia says) the principle sounds like indeed the bolter is a child of this thing.
Read the baroque german novel "Simplicissimus"; the author describes the weak penetration capability of 30 years war muskets (bouncing off harmlessly from a skull once). But indeed they are the ancestors of modern day firearms.


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Tchk, learing is never over... by hearing the word "Gyrojet" I would immediately have thought of a kind of stabilised VTOL/STOL aviation vehicle autogiro style...

How did you guys lose the war exactly?

Tethgar wrote:
How did you guys lose the war exactly?

...Erm...

Let's not go there...

Sorry I don't get the clue, what do you mean by that remark?

But to answer it: If you mean ww2, a totally imcompetent supreme commander (thanks god for that) believing he was a strategic genius , if you mean 30 years war, by starting it in the first place, it being kind of a civil war.

 Ribon Fox wrote:

It's a gun that Dirty Harry (heck, any action hero) would salivate over. On another note, if your a regular civilian, just having a bolt round in your possession can get you the chopping block. It's more temperamental than a dirty M-16, even when clean I hear, and the Mechanicus doesn't have any plans to make them any better, ever. They're obscenely heavy and canon says that an ordinary human's wrist would break if they fired it. But then, why do you see some Imperial Guard models carrying one in either pistol or assault rifle form?


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 Satan's Little Helper wrote:
In the fire warrior PS2 game they explode

And that game is terrible, they got it all wrong. They literally translated the table top fire rate to a shooter. If they'd done it right, the gun would have had around a 30-round magazine and fire a lot faster. However, I think they could still make a decent shooter if they got a decent company to make it.

Sorry, been needing to say that for a while.

 GreySkull wrote:

 Ribon Fox wrote:

It's a gun that Dirty Harry (heck, any action hero) would salivate over. On another note, if your a regular civilian, just having a bolt round in your possession can get you the chopping block. It's more temperamental than a dirty M-16, even when clean I hear, and the Mechanicus doesn't have any plans to make them any better, ever. They're obscenely heavy and canon says that an ordinary human's wrist would break if they fired it. But then, why do you see some Imperial Guard models carrying one in either pistol or assault rifle form?


Automatically Appended Next Post:

 Satan's Little Helper wrote:
In the fire warrior PS2 game they explode

And that game is terrible, they got it all wrong. They literally translated the table top fire rate to a shooter. If they'd done it right, the gun would have had around a 30-round magazine and fire a lot faster. However, I think they could still make a decent shooter if they got a decent company to make it.

Sorry, been needing to say that for a while.

That bit about breaking wrists is in the context of a SM bolter, the ones that are .75. The regular ones are .50. Though I imagine they still have quite the kick.

 Soladrin wrote:
That bit about breaking wrists is in the context of a SM bolter, the ones that are .75. The regular ones are .50. Though I imagine they still have quite the kick.

I've been wondering about the Guard officer armoury having access to Boltguns, too. Is it in the rulebook or Guard codex about the .50 version?

another factor to consider is the velocity of the round... a .50 cal round has been known to shred people just by passing within proximity of them, due to residual shrapnel and particles traveling with and splintering from the round... I imagine a .75 would do the same thing lol

 WarlordRob117 wrote:
another factor to consider is the velocity of the round... a .50 cal round has been known to shred people just by passing within proximity of them, due to residual shrapnel and particles traveling with and splintering from the round... I imagine a .75 would do the same thing lol

If a bolter round passes close enough then it would pick up the local mass increase and detonate anyway.