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Yeah, I stumbled upon this: https://www.youtube.com/watch?v=cJAXpyt8-oQ while wasting my life on youtube, and thought this might be interesting to other WH40k nerds, too. After all, if I am not mistaken, this is the real world origin for one of the most iconic ammonition types in 40k, the bolter.
How does seeing this impact my experience in the hobby, what impressed me:
-realism fix #1 (Why do they use it in 40k, while it doesn't work well in the real world): Well, at least the main drawbacks of Gyrojet guns can be explained away narratively with ease: Obviously the Imperium found a way to reliably and cheaply produce this mini-rockets with extremely high consistency.
-artistic fix? (Why do 40k bolters look so different from the real thing): in 40k bolter construction follows a very typical Imperial theme: As boxy as possible. Should I ever be in a position to influence design decisions here, I would argue towards at least integrating those sideways holes to the "barrels". There is an overarching dilemma with bolt weapons on minis and in reality, though: On minis, they are made to look heavy, following a clear rule-of-cool decision, while the main argument that was ever made in favor of gyrojets is, that the actual "gun" (handheld launch platform) can be made extremely lightweight and simple, as it has no recoil..
I guess the narrative fix to this is, that the Imperium counteracted the lightness by instead raising the calibre and amount of propellant - I got the sneaking suspicion, that these still doesn't make perfect sense from an engineering POV, but I guess its good enough to feed it into suspense of disbelief.
-sound design: NO MORE THUNDERING BOLTER SALVOES. I think hissing or whistling are much better adjectives to describe that sound... and it really isn't very loud overall.
-that plume, though: the main ignition of the projectile after leaving the weapon is definitely looking extremely cool. I am not sure how this might ever come up in a creative project of mine, but I will leave a mental note to myself, to try to find a way to include this somewhere.
1- Well, no one has really tried to make a gyrojet in 50 years or so (that I know of). It's entirely possible that someone could make one work well today. Though I imagine its just too expensive to try and the firearms we have now work fine, no-one is really trying.
2- Some conjecture that the boxy look/feel of the Marine bolter is to armor it (and perhaps the marine). Looking at those actual gyrojet guns, the sides of the launch chamber look pretty thin/weak - a bit of shrapnel or a small rock could easily take that out of action hitting or getting lodged in there.
3 Bolters are not pure gyrojets, they have a casing, and a standard propellant that gets them out of the barrel before the rocket goes off (sort of the best of both worlds) so there is recoil, though it might not have to be as much as a conventional cartridge of same same calibre.
4- so yes there will be a sound, there is a conventional propellant, though its probably not as loud as it would be if it were doing all the work. Though Marines being terror/shock troops, the bolter may be deliberately made to be louder for the fear factor.
Bolters are a weird combination of multiple different, often contradictory, concepts that mostly were just thrown together to sound awesome.
The biggest fundamental problem with the gyrojet idea is that the projectile is still accelerating when it leaves the barrel, meaning that forces such as wind can act on it much more than they can a traditional bullet before it reaches the target (and so they usually can't hit squat beyond a very limited range), and they have a minimum effective range (the projectile is not traveling at a lethal velocity when it leaves the barrel) making it even more awkward.
IRON WITHIN, IRON WITHOUT.
New Heavy Gear Log! Also...Grey Knights! The correct pronunciation is Imperial Guard and Stormtroopers, "Astra Militarum" and "Tempestus Scions" are something you'll find at Hogwarts.
Vaktathi wrote: Bolters are a weird combination of multiple different, often contradictory, concepts that mostly were just thrown together to sound awesome.
The biggest fundamental problem with the gyrojet idea is that the projectile is still accelerating when it leaves the barrel, meaning that forces such as wind can act on it much more than they can a traditional bullet before it reaches the target (and so they usually can't hit squat beyond a very limited range), and they have a minimum effective range (the projectile is not traveling at a lethal velocity when it leaves the barrel) making it even more awkward.
I've always thought the Bolter was more RPG-7 than Gyrojet.
Booster charge launches it out of the bolter at an "acceptable" velocity meaning close quarters can still hurt, then the sustainer rocket ignites making it accelerate drastically. (IRL the RPG-7 launches at 117m/s ~385fps and accelerates to 294m/s ~ 965fps.)
Close range performance is maintained by the round being explosive, but there is generally a bladed weapon of some sort for close up.
One other thing to note: bolts are apparently shot through a barrel with conventional propellant. Barrel rifling could fix one of the big problems of the gyrojets which was imparting spin on the projectile. A bolt's propulstion only need to thrust it forward since it's already spinning when it leaves the barrel. The gyrojet had its mini rocket nozzles at an angle, which was almost impossible to get just right.
The fact that the gyrojet was a failure doesn't really show that this technology can't work. It was only one project that lasted a few years and had to compete with firearms technology that has literally centuries of R&D behind it... Of course a big reason gyrojets didn't take off is that they don't offer much a conventional firearm can't do, but there are far more unrealistic things in 40k than a functioning rocket/bullet hybrid.
2- Some conjecture that the boxy look/feel of the Marine bolter is to armor it (and perhaps the marine). Looking at those actual gyrojet guns, the sides of the launch chamber look pretty thin/weak - a bit of shrapnel or a small rock could easily take that out of action hitting or getting lodged in there.
IMO a marine can't function in their intended role if they're carrying an easily destroyed weapon across their chest.. Their armour gives them the advantage of being able to charge into enemy fire, which affects their tactics. If you ran the risk of getting your gun destroyed while doing it, all the aspects of marine shock tactics would be pointless. So armouring the gun with ceramite in the same way as the marine carrying means they can charge into enemy fire and know that their gun will survive for them to fire when they get there.
AuntHerbert wrote: Yeah, I stumbled upon this: https://www.youtube.com/watch?v=cJAXpyt8-oQ while wasting my life on youtube, and thought this might be interesting to other WH40k nerds, too. After all, if I am not mistaken, this is the real world origin for one of the most iconic ammonition types in 40k, the bolter.
How does seeing this impact my experience in the hobby, what impressed me:
-realism fix #1 (Why do they use it in 40k, while it doesn't work well in the real world): Well, at least the main drawbacks of Gyrojet guns can be explained away narratively with ease: Obviously the Imperium found a way to reliably and cheaply produce this mini-rockets with extremely high consistency.
-artistic fix? (Why do 40k bolters look so different from the real thing): in 40k bolter construction follows a very typical Imperial theme: As boxy as possible. Should I ever be in a position to influence design decisions here, I would argue towards at least integrating those sideways holes to the "barrels". There is an overarching dilemma with bolt weapons on minis and in reality, though: On minis, they are made to look heavy, following a clear rule-of-cool decision, while the main argument that was ever made in favor of gyrojets is, that the actual "gun" (handheld launch platform) can be made extremely lightweight and simple, as it has no recoil..
I guess the narrative fix to this is, that the Imperium counteracted the lightness by instead raising the calibre and amount of propellant - I got the sneaking suspicion, that these still doesn't make perfect sense from an engineering POV, but I guess its good enough to feed it into suspense of disbelief.
-sound design: NO MORE THUNDERING BOLTER SALVOES. I think hissing or whistling are much better adjectives to describe that sound... and it really isn't very loud overall.
-that plume, though: the main ignition of the projectile after leaving the weapon is definitely looking extremely cool. I am not sure how this might ever come up in a creative project of mine, but I will leave a mental note to myself, to try to find a way to include this somewhere.
They were popular in 70s SF novels for some stupid reason. The Bolt gun is partially a gyrojet, partially Stainless Steel Rat Jim DiGriz's .75cal recoilless pistol and part Judge Dredd lawgiver pistol. 2000AD printed a comic version of Harry Harrison's SSR stuff as well as Judge Dredd. GW had the licence for 2000AD stuff in the 80s for rpgs and boardgames and no doubt cribbed stuff from a variety of sources. The Arbites are most definitely
"homaged" from the Judges of JD.
I'm OVER 50 (and so far over everyone's BS, too).
Old enough to know better, young enough to not give a ****.
That is not dead which can eternal lie ...
... and yet, with strange aeons, even death may die.
Well, for what is probably the millionth time in the history of my being in this hobby its time to once more say...
The Bolter, is NOT a Gyrojet. The bolter's .75cal (roughtly 19,25mm) cartridge is a dual stage shell. You can tell this from it having a casing that is ejected in the art and even sometimes the books. In older books where it was caseless, it was still a two stage round. Identifiable by the described sound of it firing, a bang of a traditional projectile, followed by the sounds of a rocket igniting and further propelling the round towards its target. The closest approximation for the bolter's ammunition would be a Rocket Assisted Projectile fired by some modern artillery. The dual stage eliminates the lack of impact force and accuracy at close ranges, and in theory for the rifle cartridge it should improve impact, and accuracy.
I'm fairly sure I've seen it mentioned in a couple books, but I could be wrong. Still, that would have no effect on the Bolter firing a two stage round, makes it more likely infact.
VictorVonTzeentch wrote: I'm fairly sure I've seen it mentioned in a couple books, but I could be wrong. Still, that would have no effect on the Bolter firing a two stage round, makes it more likely infact.
Yeah. for years I also thought the bolter was casless and I eventually went trawling through everything I had to try and find evidence. But came up empty. for good or ill the bolter fires a conventional round with a rocket inside the bullet.
What gets me though is the oversized depictions of the rounds many people like. Even at 0.75 the size of a magazine for 30 rounds would be immense. the primaris bolt rifle magazine is so tiny it wouldn't have many rounds at all in it, even at 0.75 and there are people out there claiming they fire redbull can sized rounds...
This message was edited 1 time. Last update was at 2020/06/17 00:11:48
VictorVonTzeentch wrote: I'm fairly sure I've seen it mentioned in a couple books, but I could be wrong. Still, that would have no effect on the Bolter firing a two stage round, makes it more likely infact.
Yeah. for years I also thought the bolter was casless and I eventually went trawling through everything I had to try and find evidence. But came up empty. for good or ill the bolter fires a conventional round with a rocket inside the bullet.
What gets me though is the oversized depictions of the rounds many people like. Even at 0.75 the size of a magazine for 30 rounds would be immense. the primaris bolt rifle magazine is so tiny it wouldn't have many rounds at all in it, even at 0.75 and there are people out there claiming they fire redbull can sized rounds...
Well most people do have less knowledge of this sorta stuff, so would think to inflict wounds like that you need big rounds.
Insectum7 wrote:Lol@ Victor. The piano music in that first video really sells it!
Cool weapon, never seen that one before.
Right? Its just such random choice in sound, and a cool weapon.
I've actually played with a Neopup PAW-20 and spoken to the guy who designed it.
It and the American XM-25 are probably the closest thing to a Bolter we have. The magazine on the PAW-20 is huge. There are two models the 6 round cylinder and the 7 round straight mag. Neither are very compact, although a Marine may not find them that large.
Like many things in WH40K the idea behind a Bolter is better on paper than practicality. Same with chainswords. Unless there is a drastic increase in either bullet propellant (gunpowder), rocket fuel and explosives there is no practical way to get Bolter to function.
My Photobucket account died and took my PAW-20 pictures with it. I can only find my Trade Show pictures but here is an example of what I'm talking about.
These are the PAW-20 cartridges. 20x42mm. The MV is a respectable 310m/s (1000fps). 20mm = ~ .78cal.
This is what the various warheads do to armour
High Explosive Incendiary
Semi Armour Piercing HEI
and finally the true Armour Piercing
That's against 3mm and 8mm RB500 armour. That's probably in the region of Carapace armour in WH40K terms. So it'll wreck your day if you aren't in Power Armour. Even then the correct ammo will ring your bell pretty good.The problem comes in at this point. This stuff isn't rocket propelled. You're needing an extra stage in there somewhere for the rocket motor and fuel. The 20x42mm is about on the limits of what a human can fire. Yes Marines are super-human, I get that, but the recoil on this thing is astounding. The cartridge is around 10cm long, overall. You could cut down the booster for an increased sustained motor but you'd reduce your MV a lot but the cartridge would still be hell long.
This is the newer rotary magazine. The stick-mags were retired cos they didn't work reliably. They were straight mags as opposed to the Bolter's curved mags.
Like I said, it sounds good on paper.
This message was edited 1 time. Last update was at 2020/06/17 07:31:42
Insectum7 wrote: Lol@ Victor. The piano music in that first video really sells it!
Yeah, out of all the public domain music there is, that's an odd one to pick (the song is Chopin's "Fantaisie-Impromptu" by the way).
Anyway, it's fair to assume that fuel/propellant in the far future is a lot better than what we have now. For example: considering the size of a chainsword's fuel tank, they'd run dry real fast if they weren't running on conveniently hyper efficient promethium.
Bolts being rocket-propelled, they can afford to have relatively low velocity at first, which would reduce the recoil. Magazine size is the one thing that's really hard to get around. Unless there's a way to shrink bolts or something, those magazines are going to be very low capacity...
yeah, magazine capacity is the only real problem, but let's say a standard boltgun has a capacity of 15-20"rds", so stormbolter cap of 30-40, assault bolter(drum) 25rds.
but with the size of the required magazines, an Astartes can feasibly carry 4-6 of them(just looking at the mag pouches and space on marine). So that's not really a large volume of bolts but....servo skulls are a thing so mid battle rearmament is a thing, air dropped ammo caches, etc.
the other thing is that an Astartes is at one with their boltgun, so accuracy(even in combat) should be ridiculous like an 80% hit ratio with a most likely 90% hit:kill ratio. So the need to carry a ton of bolts is lessened than say a guardsman that shoots a flashlight and needs as many shots as possible.
Racerguy180 wrote: yeah, magazine capacity is the only real problem, but let's say a standard boltgun has a capacity of 15-20"rds", so stormbolter cap of 30-40, assault bolter(drum) 25rds.
but with the size of the required magazines, an Astartes can feasibly carry 4-6 of them(just looking at the mag pouches and space on marine). So that's not really a large volume of bolts but....servo skulls are a thing so mid battle rearmament is a thing, air dropped ammo caches, etc.
the other thing is that an Astartes is at one with their boltgun, so accuracy(even in combat) should be ridiculous like an 80% hit ratio with a most likely 90% hit:kill ratio. So the need to carry a ton of bolts is lessened than say a guardsman that shoots a flashlight and needs as many shots as possible.
No matter which way you slice it, different aspects of the depiction of marines with bolters won't work. ie If they have 15 round clips, they aren't going full auto on anyone. If they have 150 cal rounds like some people enthusiastically decree, then either their magazines are longer than their arms, or they only have 5 rounds etc.
Even the awesome Astartes short film on youtube depicts a more reasonable size of bolt along with semi and full auto.
75cal 30 round sickle mag seems actually doable, at the cost of bolt rounds being a measly ~19.5mm in diameter.
primaris heavy bolt pistols run into this problem even more as they're using heavy bolter rounds (which are supposed to be 100cal if you ignore fan exaggeration). They're unlikely to have more than 5 rounds in them given that size.
I wouldnt shake a stick at 5 HEAVY bolts, if a reg bolt is as powerful as they say it is, it's like going into combat with a .460S&W mag versus a .45ACP. both powerful, just one significantly more so.
Astartes is probably the best depiction I've seen. Kinda like the bolts are .458SOCOM sized so they'd be able to have decent capacity.
Another thing that hasnt been discussed is miniaturization of electronics, guidance systems & materials. who knows what kind of alloy the barrels are made out of, they might be able to withstand pressures unthinkable today, the action is never really detailed, i.e. open/closed locking/firing system, radially delayed blowback, tilting??? no idea, there might be an entirely novel design solution to the the cartridge/payload delivery locking system.
primaris heavy bolt pistols run into this problem even more as they're using heavy bolter rounds (which are supposed to be 100cal if you ignore fan exaggeration). They're unlikely to have more than 5 rounds in them given that size.
You're thinking of the Absolver Bolt Pistol for the Heavy Bolts, Heavy Bolt Pistols just utilize the longer barrel and enhanced shells of the Bolt Rifle. Also they are 1 Caliber, vs the .75 of a normal Bolter. 100 Cal would be way bigger.
Racerguy180 wrote:
Another thing that hasnt been discussed is miniaturization of electronics, guidance systems & materials. who knows what kind of alloy the barrels are made out of, they might be able to withstand pressures unthinkable today, the action is never really detailed, i.e. open/closed locking/firing system, radially delayed blowback, tilting??? no idea, there might be an entirely novel design solution to the the cartridge/payload delivery locking system.
None of those listed things address, the issue of the size of the bolt itself. The .75 is the diameter of the bullet itself, so they'd still be a big round. Miniaturizing the electronics and the future materials can account for the effectiveness of the rocket ignition, additional accuracy and increased payload. Also it would account for some of the more advanced payloads they can carry. The Action and Barrel dont really have an effect on the amount of munitions the weapons can carry. But would affect other functions like being able to operate in the Void or other less than ideal conditions. So we can assume they are made from incredibly resilent and sturdy stuff, particularly when you take into account that some of these things have been maintained and used for 10 Thousand Years.
This message was edited 1 time. Last update was at 2020/06/25 16:12:31
Waiting for my shill money from Spiral Arm Studios
A Bolt round is what you get when you combine a Gyrojet with a normal firearm projectile. IE: it is a normal cased round with an explosive charge that accelerates the projectile. A projectile that has a small rocket in its base as well as an explosive warhead. This solves the main issue with gyrojets, which was utter lack of lethality at close range. Plus you eliminate all of the problems that caseless ammo has. People need to stop trying to make caseless ammo happen, its a terrible idea and needs to die.
In theory, we could make such a weapon today with a larger caliber. Its not hard to make explosive ammo.
Have a warhead similar to those WW2 rounds, put it in a larger caliber so you can fit the gyrojet rocket in there. We're probably talking at minimum .458 socom, and you'd basically have a bolter, though you might need to step to 470 or even a 50.
VictorVonTzeentch wrote: But would affect other functions like being able to operate in the Void or other less than ideal conditions.
Actually, even modern firearms function perfectly fine in a vacuum, or even underwater. Smokeless powder contains its own oxidant so it doesn't need atmospheric oxygen to work. Nor does a lack of atmospheric pressure interfere with its ability to cycle. Technically, it would achieve a negligible increase in velocity due to lack of air resistance.
Now while a .75 cal round would be large, it would not be comically so. You could still have a 20-30 round double stack magazine and have it only be slightly longer than a normal caliber magazine.
This message was edited 1 time. Last update was at 2020/06/26 15:44:42
Self-proclaimed evil Cat-person. Dues Ex Felines
Cato Sicarius, after force feeding Captain Ventris a copy of the Codex Astartes for having the audacity to play Deathwatch, chokes to death on his own D-baggery after finding Calgar assembling his new Eldar army.
Boltgun ammo is similar in concept in that both examples utilize self-propulsion.
However, the two are different in that bolts are tandem charge ammunition with rocket propulsion, whereas gyrojet's built in propulsion is to to increase range and accuracy only.
Automatically Appended Next Post:
godardc wrote: Actually, a very interesting video. Do you think 3d printing could help cheapen the ammunition, quicken the production and makes it more reliable ?
3D printers alone aren't suitable for mass production, although combined use of rapid prototyping with standard methods of mass production might.
No 3d printers will ever replace standardization in terms of mass producing - matter of fact, the concept of mass production only came about because of standardization.
This message was edited 4 times. Last update was at 2020/06/26 19:07:01
skchsan wrote: Boltgun ammo is similar in concept in that both examples utilize self-propulsion.
However, the two are different in that bolts are tandem charge ammunition with rocket propulsion, whereas gyrojet's built in propulsion is to to increase range and accuracy only.
Like an RPG-7 (or most numbers, it's a booster and sustainer)
Automatically Appended Next Post:
godardc wrote: Actually, a very interesting video. Do you think 3d printing could help cheapen the ammunition, quicken the production and makes it more reliable ?
3D printers alone aren't suitable for mass production, although combined use of rapid prototyping with standard methods of mass production might.
No 3d printers will ever replace standardization in terms of mass producing - matter of fact, the concept of mass production only came about because of standardization.
I've been to a bullet casing and cannon shell casing factory, from foundry to loaded projectile, there are a couple of tricks that can be done, many of which they are already doing like induction annealing but there isn't much that can be improved. Sure many wrong people have said that about many technologies in the past but it's a pretty slick and streamlined system.
(the song is Chopin's "Fantaisie-Impromptu" by the way).
