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2019/01/22 02:27:16
Subject: I finally found the Boltgun's ancient roots... AGS-30
Fully automatic 30mm "grenade" but if you look at the "grenade" it is more bolt than grenade. I could see something this scale being used by a being of the physical scale of a Space Marine
Consummate 8th Edition Hater.
2019/01/22 02:28:07
Subject: I finally found the Boltgun's ancient roots... AGS-30
Aye, I can see it as an HB but also maybe a 20mm version would make a bolt gun.
It's more than the very advanced grenades (which more resemble what we expect of a "bolt" from a boltgun).
It's that it is a very simple weapon system. A simple blow-back heavy buffer design is pretty much right up the alley for 40ks backwards technologies.
Chop off the tripod (quadpod?) and long barrel and you've got something that is about the right physical scale for a Spacemarine to consider a carbine sized weapon.
Mostly thinking physical dimensions needed for the mechanism to operate and the feed mechanism scales vs the "sub-cal" bolters used by the Sorortias or other non-augmented humans vs the Boltgun used by a Spacemarine is noted as being "large" than the boltgun in use by say a Commisar.
Either way, even for the Orks in all of us. That's a lot of dakka.
This message was edited 1 time. Last update was at 2019/01/22 02:37:06
Consummate 8th Edition Hater.
2019/01/22 02:38:28
Subject: I finally found the Boltgun's ancient roots... AGS-30
The caliber or the gun itself, it would make sense that the SM bolter would be larger to account for their larger size, but they can keep the caliber and the internals the same.
Bobthehero wrote: The caliber or the gun itself, it would make sense that the SM bolter would be larger to account for their larger size, but they can keep the caliber and the internals the same.
The fluff is kind of inconsistent on Bolters. There are often mentions of sub-caliber boltguns used by "normal humans" while the "recoil" of a space marine's boltgun would break a man's arm. Other times, they ignore it entirely. *shrug*
Either way, I am pretty sure that the boltgun is a simple blowback operated weapon, likely extremely mechanically simple.
Consummate 8th Edition Hater.
2019/01/22 03:37:47
Subject: I finally found the Boltgun's ancient roots... AGS-30
Either/Or wrote: I thought bolters were always described as basically gyrojets (which never made sense with the recoil description, but that’s a whole other issue).
Nor with the casings ejecting from the boltguns. The fluff isn't very consistent. I kind of envision the above all my life anyways. Short-brass based micro-rockets. Made the most sense with the art and the crazy not the same on every day of the week fluff.
Consummate 8th Edition Hater.
2019/01/22 04:02:26
Subject: I finally found the Boltgun's ancient roots... AGS-30
Either/Or wrote: I thought bolters were always described as basically gyrojets (which never made sense with the recoil description, but that’s a whole other issue).
They're a hybred between a 20mm grenade launcher, and a gyrojet weapon. They use shells and have recoil because they use a standard gunpowder charge to fire, after which the gyrojet takes over. But that powder charge is more to get it up to a decent starting speed for the rocket to kick in, rather than a full powered 20mm round. Which is why you never see a bolter with a butt.
2019/01/22 05:59:12
Subject: I finally found the Boltgun's ancient roots... AGS-30
I always thought that they didn't have stocks because Astartes and Sororitas wouldn't be able to place it against their shoulder in power armor, and the armor's actuators and stabilizers take care of most of the recoil control and aiming.
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2019/01/22 06:12:26
Subject: I finally found the Boltgun's ancient roots... AGS-30
I've always thought the Fostech Origin 12 shotgun made for a pretty fitting Bolter modern lookalike.
This message was edited 1 time. Last update was at 2019/01/22 06:19:16
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2019/01/22 07:38:26
Subject: I finally found the Boltgun's ancient roots... AGS-30
To my understanding, bolters are roughly 20mm, fully automatic, armor piercing, RPG launchers. The primary charge is subsonic, and simply forces the round out of the barrel at a decent speed, then the gyrojet rocket takes over and the round flies much more like a missile.
The fluff is inconsistent as to the caliber of "regular human" bolters in relation to astartes bolters. But I was under the impression that astartes and sororitas bolters do not have stocks ("butts" to some people) because power armor would make them impossible to use. Regular human pattern bolters can and do have stocks.
As far as I am aware, that is an original model and not a conversion.
This message was edited 3 times. Last update was at 2019/01/22 07:58:47
2019/01/22 08:55:18
Subject: I finally found the Boltgun's ancient roots... AGS-30
Inquisitor Lord Katherine wrote: I always thought that they didn't have stocks because Astartes and Sororitas wouldn't be able to place it against their shoulder in power armor, and the armor's actuators and stabilizers take care of most of the recoil control and aiming.
Either/Or wrote: I thought bolters were always described as basically gyrojets (which never made sense with the recoil description, but that’s a whole other issue).
No, that was people trying to tie a fictional bit of equipment to a real thing, while apparently not understanding how either worked. It's more akin to a rocket assisted projectile, scaled down from an artillery shell to a rifle round.
Most people trimmed the stocks off those 90s plastic boltguns, as they didn't fit well on the models, but one of the metal Captains from 1991 - with boltgun and power fist - is holding his boltgun with his arm extended, and the stock is there, braced against the bottom edge of the shoulder pad.
Other weapons such as plasma guns and meltaguns had stocks sculpted on; with one-piece metal models, adding details such as stocks, attachments like scopes or lights, pouches and grenades are a good way of filling voids in the model that would otherwise make them difficult to mould and/or cast correctly.
This message was edited 1 time. Last update was at 2019/01/22 09:20:54
2019/01/22 12:23:26
Subject: Re:I finally found the Boltgun's ancient roots... AGS-30
I like to imagine that a Bolter is something like a cross between a shotgun and a gyrojet, using a 'kicker' and a small brass casing to get the round moving out the barrel so that it's still lethal until the shell's internal propellant gets going. So you get a kick and an ejection of brass, but nothing like you'd get out of, say, a Barrett .50 cal.
2019/01/22 14:02:16
Subject: I finally found the Boltgun's ancient roots... AGS-30
Nurglitch wrote: So you get a kick and an ejection of brass, but nothing like you'd get out of, say, a Barrett .50 cal.
The boltgun is supposed to be considerably more powerful than a .50 cal.
Yes, and his point was that because the projectile supplements the initial propellant charge (the source of recoil) with an onboard rocket, the recoil should be low compared to the momentum on-target.
Also, caliber can be highly misleading when discussing rocket ammunition, which tends to be more similar to pistol bullets in ballistic design. .50 BMG has a conventional boat-tailed spitzer design with a high ballistic coefficient, making for a very long bullet relative to its width- a typical projectile mass is 45 grams. The gyrojet was also .50 caliber, but each stubby projectile was only around 12 grams. Scaling up the Gyrojet design to .75 caliber yields a hypothetical projectile mass of around 39 grams, still less than the mass of the .50 BMG, but the use of an explosive warhead would significantly increase lethality.
So, suppose this 39g projectile attains the same velocity as the .50 BMG (there are good reasons not to exceed this, which aren't worth going into), but suppose that half of this momentum is provided by the rocket motor in-flight. This gives it a total recoil impulse of only 43% that of the .50 BMG, and around double the recoil impulse of a typical battle rifle cartridge (eg 7.62x54R or 7.62 NATO).
Give it a simple straight blowback action, and the thing will have to weigh 20+lbs, which should do a decent job of soaking up that recoil impulse. It will be highly unpleasant for a human to fire from the shoulder and a stock will be mandatory, but a power-armored superhuman should have no problem.
The AGS-30, PAW, and XM25 are all incomparable to bolters in that none use a dual-propellant system, so all rely on extremely large, low-velocity projectiles using a high-low pressure system. The use of onboard propellant as a supplement to the initial charge really does fundamentally change the nature of the weapon.
This message was edited 2 times. Last update was at 2019/01/22 17:26:25
catbarf wrote: Yes, and his point was that because the projectile supplements the initial propellant charge (the source of recoil) with an onboard rocket, the recoil should be low compared to the momentum on-target.
Also, caliber can be highly misleading when discussing rocket ammunition, which tends to be more similar to pistol bullets in ballistic design. .50 BMG has a conventional boat-tailed spitzer design with a high ballistic coefficient, making for a very long bullet relative to its width- a typical projectile mass is 45 grams. The gyrojet was also .50 caliber, but each stubby projectile was only around 12 grams. Scaling up the Gyrojet design to .75 caliber yields a hypothetical projectile mass of around 39 grams, still less than the mass of the .50 BMG, but the use of an explosive warhead would significantly increase lethality.
So, suppose this 39g projectile attains the same velocity as the .50 BMG (there are good reasons not to exceed this, which aren't worth going into), but suppose that half of this momentum is provided by the rocket motor in-flight. This gives it a total recoil impulse of only 43% that of the .50 BMG, and around double the recoil impulse of a typical battle rifle cartridge (eg 7.62x54R or 7.62 NATO).
Give it a simple straight blowback action, and the thing will have to weigh 20+lbs, which should do a decent job of soaking up that recoil impulse. It will be highly unpleasant for a human to fire from the shoulder and a stock will be mandatory, but a power-armored superhuman should have no problem.
The AGS-30, PAW, and XM25 are all incomparable to bolters in that none use a dual-propellant system, so all rely on extremely large, low-velocity projectiles using a high-low pressure system. The use of onboard propellant as a supplement to the initial charge really does fundamentally change the nature of the weapon.
Excellent analysis, and I pretty much agree with all of that.
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It's more akin to a rocket assisted projectile, scaled down from an artillery shell to a rifle round.
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