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For some reason, I always pictured the Lascannon as being very light for a weapon of it's size. It's a laser weapon so the only heft would be in the heat sink for it. It probably depends on the world and material they are made out of. Maybe from some worlds it's made out of a hyper advanced space metal and on others it's made out of wrought iron? Just some fan speculation there.

The heavy bolter is referred to being... well.. heavy. In the IG codex it's called the "Back breaker" if I remember right.

Why aren't these weapons on wheel, though? They aren't exactly man portable being the size of modern howitzers. Unless they are a lot lighter than you think.

 Swastakowey wrote:
I prefer my men to be a little more beleivable personally.

If you want your little men to be believable, then you picked the wrong game.

 Wyzilla wrote:

 Swastakowey wrote:
Ok hold up... The only thing close to a bolter shell being used in real life was one of hitlers wonder weapons. It had to sit in a hill bunker complex, it used magnets and rocketry to propell the shell accross the channel. It had an extensive vent system and the shell wasnt too big either. I am not sure if it even got to fire...

Other than that i am far from convinced a bolter round can be made (along with a portable weapon) today. for one the gun would have to be HUGE and heavy, the round would be loud and visible, it would not be accurite and it would not be able to be aimed easily and the gun would need some kind of super freezer to keep it cool.

Rail guns yes, but thats not what we are talking about.

And also the idea of a boltgun in every way is impractical for real life.

Lolwut? No, they're called grenade launchers. They serve the exact same purpose, only airburst launchers are designed for multiple casualty infliction while the bolter typically tries to cause a single casualty. We could build one quite easily with modern day tech, just that it would lack the specific range and penetration power, but it'd function just the same. Only we don't need it because we don't fight aliens with hide having the strength of heavy armor or giant battlemechs. But we have the tech to make a heavy gun out of them. It'd be a large 20mm shell, but it'd work.

We have the technology to make guided shells, just they'd be a lot longer to make room for the booster. Hell, we actually are a step above the Imperium as we could make those shells guided. Because self guided bullets are now a thing as of 2012 and increase accuracy of snipers for long-distance targets. The only problem keeping us from making one besides it being a toy is the expense of doing so and it's lack of use on a modern battlefield.

Spoiler:

We could definitely build a bolter turret minus the alien alloys we don't have access to in reality. You couldn't shoulder it unless you wanted a busted arm, but we could certainly make it.

grenade launchers arent rocket propelled nor are hand held ones fully automatic... grenade launchers arent homing and fire in arcs.

Right now all i see is the assumption we can make it because we have SOME of the things that make a bolter, but we dont have a way at all to combine it all into one small package.

Find me a weapon thats anything like a bolter. Find me a real life fully automatic .75 round weapon that fires explosive rocket propelled shells that are handheld and dont kill the user.

Then i will reply.

Black Crusade lists a heavy bolter as 40kg, and "legion" heavy bolters (Space Marine versions) as 45kg.

That's heavy as gak. I realize now that one of my players who was carrying an autocannon (also 40kg) was 6kg over her carrying limit...

 Swastakowey wrote:

 Wyzilla wrote:

 Swastakowey wrote:
Ok hold up... The only thing close to a bolter shell being used in real life was one of hitlers wonder weapons. It had to sit in a hill bunker complex, it used magnets and rocketry to propell the shell accross the channel. It had an extensive vent system and the shell wasnt too big either. I am not sure if it even got to fire...

Other than that i am far from convinced a bolter round can be made (along with a portable weapon) today. for one the gun would have to be HUGE and heavy, the round would be loud and visible, it would not be accurite and it would not be able to be aimed easily and the gun would need some kind of super freezer to keep it cool.

Rail guns yes, but thats not what we are talking about.

And also the idea of a boltgun in every way is impractical for real life.

Lolwut? No, they're called grenade launchers. They serve the exact same purpose, only airburst launchers are designed for multiple casualty infliction while the bolter typically tries to cause a single casualty. We could build one quite easily with modern day tech, just that it would lack the specific range and penetration power, but it'd function just the same. Only we don't need it because we don't fight aliens with hide having the strength of heavy armor or giant battlemechs. But we have the tech to make a heavy gun out of them. It'd be a large 20mm shell, but it'd work.

We have the technology to make guided shells, just they'd be a lot longer to make room for the booster. Hell, we actually are a step above the Imperium as we could make those shells guided. Because self guided bullets are now a thing as of 2012 and increase accuracy of snipers for long-distance targets. The only problem keeping us from making one besides it being a toy is the expense of doing so and it's lack of use on a modern battlefield.

Spoiler:

We could definitely build a bolter turret minus the alien alloys we don't have access to in reality. You couldn't shoulder it unless you wanted a busted arm, but we could certainly make it.

grenade launchers arent rocket propelled nor are hand held ones fully automatic... grenade launchers arent homing and fire in arcs.

Right now all i see is the assumption we can make it because we have SOME of the things that make a bolter, but we dont have a way at all to combine it all into one small package.

Find me a weapon thats anything like a bolter. Find me a real life fully automatic .75 round weapon that fires explosive rocket propelled shells that are handheld and dont kill the user.

Then i will reply.

We don't have one because it's redundant to use against people. The point stands however that we have the tech to make one if we wanted, just that it'd be pointless for us to use. Obviously it wouldn't be carried around like a normal rifle, rather an AT weapon mounted on a large tripod manned by a full crew rather than a single person weapon.

 Wyzilla wrote:

 Swastakowey wrote:

 Wyzilla wrote:

 Swastakowey wrote:
Ok hold up... The only thing close to a bolter shell being used in real life was one of hitlers wonder weapons. It had to sit in a hill bunker complex, it used magnets and rocketry to propell the shell accross the channel. It had an extensive vent system and the shell wasnt too big either. I am not sure if it even got to fire...

Other than that i am far from convinced a bolter round can be made (along with a portable weapon) today. for one the gun would have to be HUGE and heavy, the round would be loud and visible, it would not be accurite and it would not be able to be aimed easily and the gun would need some kind of super freezer to keep it cool.

Rail guns yes, but thats not what we are talking about.

And also the idea of a boltgun in every way is impractical for real life.

Lolwut? No, they're called grenade launchers. They serve the exact same purpose, only airburst launchers are designed for multiple casualty infliction while the bolter typically tries to cause a single casualty. We could build one quite easily with modern day tech, just that it would lack the specific range and penetration power, but it'd function just the same. Only we don't need it because we don't fight aliens with hide having the strength of heavy armor or giant battlemechs. But we have the tech to make a heavy gun out of them. It'd be a large 20mm shell, but it'd work.

We have the technology to make guided shells, just they'd be a lot longer to make room for the booster. Hell, we actually are a step above the Imperium as we could make those shells guided. Because self guided bullets are now a thing as of 2012 and increase accuracy of snipers for long-distance targets. The only problem keeping us from making one besides it being a toy is the expense of doing so and it's lack of use on a modern battlefield.

Spoiler:

We could definitely build a bolter turret minus the alien alloys we don't have access to in reality. You couldn't shoulder it unless you wanted a busted arm, but we could certainly make it.

grenade launchers arent rocket propelled nor are hand held ones fully automatic... grenade launchers arent homing and fire in arcs.

Right now all i see is the assumption we can make it because we have SOME of the things that make a bolter, but we dont have a way at all to combine it all into one small package.

Find me a weapon thats anything like a bolter. Find me a real life fully automatic .75 round weapon that fires explosive rocket propelled shells that are handheld and dont kill the user.

Then i will reply.

We don't have one because it's redundant to use against people. The point stands however that we have the tech to make one if we wanted, just that it'd be pointless for us to use. Obviously it wouldn't be carried around like a normal rifle, rather an AT weapon mounted on a large tripod manned by a full crew rather than a single person weapon.

Exactly, we cant. A crewed artillery peice is nothing at all like a bolter. I have already said we can do those. Miniaturized ones are not possible.

 Swastakowey wrote:

 Wyzilla wrote:

 Swastakowey wrote:

 Wyzilla wrote:

 Swastakowey wrote:
Ok hold up... The only thing close to a bolter shell being used in real life was one of hitlers wonder weapons. It had to sit in a hill bunker complex, it used magnets and rocketry to propell the shell accross the channel. It had an extensive vent system and the shell wasnt too big either. I am not sure if it even got to fire...

Other than that i am far from convinced a bolter round can be made (along with a portable weapon) today. for one the gun would have to be HUGE and heavy, the round would be loud and visible, it would not be accurite and it would not be able to be aimed easily and the gun would need some kind of super freezer to keep it cool.

Rail guns yes, but thats not what we are talking about.

And also the idea of a boltgun in every way is impractical for real life.

Lolwut? No, they're called grenade launchers. They serve the exact same purpose, only airburst launchers are designed for multiple casualty infliction while the bolter typically tries to cause a single casualty. We could build one quite easily with modern day tech, just that it would lack the specific range and penetration power, but it'd function just the same. Only we don't need it because we don't fight aliens with hide having the strength of heavy armor or giant battlemechs. But we have the tech to make a heavy gun out of them. It'd be a large 20mm shell, but it'd work.

We have the technology to make guided shells, just they'd be a lot longer to make room for the booster. Hell, we actually are a step above the Imperium as we could make those shells guided. Because self guided bullets are now a thing as of 2012 and increase accuracy of snipers for long-distance targets. The only problem keeping us from making one besides it being a toy is the expense of doing so and it's lack of use on a modern battlefield.

Spoiler:

We could definitely build a bolter turret minus the alien alloys we don't have access to in reality. You couldn't shoulder it unless you wanted a busted arm, but we could certainly make it.

grenade launchers arent rocket propelled nor are hand held ones fully automatic... grenade launchers arent homing and fire in arcs.

Right now all i see is the assumption we can make it because we have SOME of the things that make a bolter, but we dont have a way at all to combine it all into one small package.

Find me a weapon thats anything like a bolter. Find me a real life fully automatic .75 round weapon that fires explosive rocket propelled shells that are handheld and dont kill the user.

Then i will reply.

We don't have one because it's redundant to use against people. The point stands however that we have the tech to make one if we wanted, just that it'd be pointless for us to use. Obviously it wouldn't be carried around like a normal rifle, rather an AT weapon mounted on a large tripod manned by a full crew rather than a single person weapon.

Exactly, we cant. A crewed artillery peice is nothing at all like a bolter. I have already said we can do those. Miniaturized ones are not possible.

Gee, I wonder what that is. Oh, right, a crew-served heavy cannon AKA an IG heavy bolter.

The heavy bolter is not a crew served artillery piece.

 Swastakowey wrote:
The heavy bolter is not a crew served artillery piece.

Because in W40K scale it's simply an HMG. In modern combat, it's firepower is equal to that of a light cannon. It sure as feth wouldn't have two guys handling extremely dangerous ammunition that could accidentally detonate before use thanks to the mass reactive cap.

 Wyzilla wrote:

 Swastakowey wrote:
The heavy bolter is not a crew served artillery piece.

Because in W40K scale it's simply an HMG. In modern combat, it's firepower is equal to that of a light cannon. It sure as feth wouldn't have two guys handling extremely dangerous ammunition that could accidentally detonate before use thanks to the mass reactive cap.

No its not. You know very little on the topic it seems

 Swastakowey wrote:

 Wyzilla wrote:

 Swastakowey wrote:
The heavy bolter is not a crew served artillery piece.

Because in W40K scale it's simply an HMG. In modern combat, it's firepower is equal to that of a light cannon. It sure as feth wouldn't have two guys handling extremely dangerous ammunition that could accidentally detonate before use thanks to the mass reactive cap.

No its not. You know very little on the topic it seems

Uh, yes it is. It's a 1.00 Caliber cannon firing rocket propelled shells at possibly full-auto and belt fed. The rounds are extremely lethal and pretty much have blasting caps on the front and serves as no viable good counter to anything on the battlefield to date besides simply being a fun toy. We could build one with modern tech, hell, we've built better things than it. The problem with it is that it's pretty much three different weapons all rolled into one that ends up as a jack of none. It's mean to counter super-heavy infantry, which we don't have on the battlefield currently and thus do just fine and dandy with 40mm grenade launchers, especially airburst which will destroy more than a single infantry target like a heavy bolter. There's no reason why we couldn't build one, we have the tech. It'd probably take five years or more to design I'd guess if it was well funded, just that it's completely useless on the modern battlefield unlike in W40K. However there's absolutely no reason why we couldn't build a heavy bolter. The reason why we don't is because we're not stupid (or at least not to the degree to build a pointless weapon with no purpose other than to be fun to use). The only thing we couldn't do is give it the penetration power it has in W40K thanks to our lack of access to any magical admantanium super-metal. That and the size of the round, which would likely be a bit longer and maybe a tad thicker in order to store more fuel and space to fire the round out of the gun before igniting the rockets.

uhuh and people in the 50s said we had the tech to build biospheres. And as most of those claims (like yours) is bull crap.

And no its not an artillery piece. Go learn what artillery is.

 Swastakowey wrote:
uhuh and people in the 50s said we had the tech to build biospheres. And as most of those claims (like yours) is bull crap.

And no its not an artillery piece. Go learn what artillery is.

It's a crew manned anti-armor gun. That's what a bolter is. There really is no disputing this, as it's not an anti infantry gun, those are what stubbers are for. It's mean to counter heavily armored infantry that we have no equivalent to besides light tanks.

And did you even pay attention to what I posted? All a bolt is, is a mass reactive RPG with an additional charge to kick the shell out of the gun before the mini rockets fire and spin it to its target. That's all a bolter is. You know what it's made to fight? Heavy heavy infantry and light vehicles. Tyranids, Astartes and MEQ, Carapace armor, and the bigger Ork Boyz. There's nothing like these in real life. The only thing it'd be useful at all for fighting is light armor (although still be fairly crappy because we don't have super strong magical) alloys. But the point is that we could make a functional mass-reactive RPG automatic gun. It'd work. There's no reason why it wouldn't. But all it'd be good for is just showing off how big your is to everyone else and nothing else. It'd be an ace of none. Great at taking down single infantry with direct hits.... but hard to aim and would likely need a new barrel fast from even burst fire depending on how much fuel is packed into the round or gunpowder to get it out of the barrel. It might punch through light armor... but by the time you'd carried over, set it up, and loaded it and brought new barrels in case they melt... you could have already killed the armor long before with modern AT weapons. You could use it against fortified positions like a bunker.... but standard bolts are only really useful for single targets, where using an airburst frag or simply firing a rocket at the structure would be more effective and fast.

We could build it, easily within several years. The problem is that it'd be large, bulky, and pretty much useless. And require a crew to maintain the weapon to make sure the barrel wasn't toasted by any sustained fire (again, depending on how the rounds are made). It'd also likely be larger, and certainly couldn't be carried around by two guys (although that's already outlandish and requires the two guys to be superhuman or vastly above average), with the barrel also likely being much longer than standard and having to be swapped out similar to German MG crews swapping the barrels of MG42 from sustained fire, only with significantly less fire with the HB.

However, as it'd be firing a 1.00 Caliber Mass-Reactive round, it'd fullfill the definition of a Heavy Bolter. Which has also varied greatly in design in W40K.

Edit-

And we did build a mostly functioning biosphere. Really man, times, keep up with them. We have the tech to build a heavy bolter equal with modern day tech (just suffering from less penetration power and likely range), just that a fething Patton from World War II would be more useful. The only reason why weapons as outlandish as the heavy bolter exist in W40K is their arms race with armor, which armor's significantly won so far- although it helps the guys with the armor are a posthuman augmented effectual subspecies of humanity.

Yea every time you say "we could build it in several years but, but, but..." all that shows is you are speculating. Artillery is not an anti armour gun either. Nor is it an rpg? Make up your mind.

 Swastakowey wrote:
Yea every time you say "we could build it in several years but, but, but..." all that shows is you are speculating. Artillery is not an anti armour gun either. Nor is it an rpg? Make up your mind.

That's because that's what are version of what it would be. And by AT, I mean anti-tank, not artillery. It'd be similar to the old anti tank guns if it wasn't mounted on a vehicle. It wouldn't be like the HMG it's seen as in W40K, rather a heavy gun more complex than your usual full auto 40mm frag launchers due to the rounds being rocket-propelled along with being mass reactive.



And the speculation is because you don't simply churn out a weapon in a year, we don't pull new weapons systems of thin air, it takes years of research (feth, just look at the poor XM8 and other lightweight rifle projects). Building a functioning bolter is completely within our technology as of now (especially with nanotech computer chips capable of being fitted into bullets). The problem is packaging everything together, but we could certainly do it with funds put into the project building off the current tech of guided bullets and explosives. Just that the reward would be pretty much a useless brick for what would be millions of dollars of investment. Woopee.

Because in other words we cant make it without learning. Saying we just need to do this etc is not backed up by anything but speculation. Now im sick of reading your pointless rants on how we dont yet know how to make a bolter (which is what im saying anyways) and its wildly off topic so ill leave you to your ramblings and ill think what i think.

You may be right, give several years (however long that may be) and maybe its possible but not now. We cannot make one yet. As i stated. Not that the concept of the heavy bolter works anyway.

So lets leave it.

Applying even a modicum of real-world physics or common sense to 40k fluff will make your head hurt. Don't even bother. Heavy weapons are heavy.

 Harriticus wrote:
Applying even a modicum of real-world physics or common sense to 40k fluff will make your head hurt. Don't even bother. Heavy weapons are heavy.

Definitely something i have learnt over the last few days. I am officially not going to bother with the fluff anymore haha. It just doesnt sit right.

Dark Heresy puts a HB at 40kg.

 Harriticus wrote:
Applying even a modicum of real-world physics or common sense to 40k fluff will make your head hurt. Don't even bother. Heavy weapons are heavy.

Well, humanity is a race of reality warpers capable of manipulating the world around them in W40K.

 Swastakowey wrote:
Because in other words we cant make it without learning. Saying we just need to do this etc is not backed up by anything but speculation. Now im sick of reading your pointless rants on how we dont yet know how to make a bolter (which is what im saying anyways) and its wildly off topic so ill leave you to your ramblings and ill think what i think.

You may be right, give several years (however long that may be) and maybe its possible but not now. We cannot make one yet. As i stated. Not that the concept of the heavy bolter works anyway.

So lets leave it.

It's pretty irritating to see him put together such a well-constructed and intelligent post and you throw it away with an ignorant rant.

I could give you a pile of lumber, nails, screws, and etc. and you couldn't build a house in a day either. It takes designing and engineering no matter how easy and known the separate components are.

We could easily make a bolter now. We have already built all the component parts, just not with certain imaginary materials that 40k claims. It's just incredibly, stupidly impractical.

Ferros wrote:

 Swastakowey wrote:
Because in other words we cant make it without learning. Saying we just need to do this etc is not backed up by anything but speculation. Now im sick of reading your pointless rants on how we dont yet know how to make a bolter (which is what im saying anyways) and its wildly off topic so ill leave you to your ramblings and ill think what i think.

You may be right, give several years (however long that may be) and maybe its possible but not now. We cannot make one yet. As i stated. Not that the concept of the heavy bolter works anyway.

So lets leave it.

It's pretty irritating to see him put together such a well-constructed and intelligent post and you throw it away with an ignorant rant.

I could give you a pile of lumber, nails, screws, and etc. and you couldn't build a house in a day either. It takes designing and engineering no matter how easy and known the separate components are.

We could easily make a bolter now. We have already built all the component parts, just not with certain imaginary materials that 40k claims. It's just incredibly, stupidly impractical.

The problem is that his definition of 'right now' is apparently not the real one. R&D doesn't pull new toys out of its , they spend years, even decades until they give us a nice shiny weapon. We don't suddenly have laser turrets on aircraft and ships because we did it one year 'because we had the capability'. Considering it wouldn't involve building a complex device like a laser and the energy required to power it, but rather just finding the best way to cram a rocket and the black powder to blow it out the gun while keeping it accurate, I don't see why anyone couldn't see it being completely possible with modern tech. Especially considering it's a lot easier now to prototype and test equipment digitally with a computer rather than having to build it from scratch or run off theoretical math that doesn't involve a more trustworthy computer system to run it really speeds up the process. Two decades ago? Unlikely without a decade of work. Now? Pft. Five to six years. Build it in a computer model until you figure out a way to make the round work, then build it in real life and then design a system to deliver the bolt. But I doubt anyone would shell out the money needed for a project like it, so it's unlikely we'd ever see a true bolter in action unless we suddenly develop super heavy infantry clothed in literally impossible metals that cannot exist.

 Swastakowey wrote:
Because in other words we cant make it without learning. Saying we just need to do this etc is not backed up by anything but speculation. Now im sick of reading your pointless rants on how we dont yet know how to make a bolter (which is what im saying anyways) and its wildly off topic so ill leave you to your ramblings and ill think what i think.

You may be right, give several years (however long that may be) and maybe its possible but not now. We cannot make one yet. As i stated. Not that the concept of the heavy bolter works anyway.

So lets leave it.

http://en.wikipedia.org/wiki/Objective_Individual_Combat_Weapon
http://en.wikipedia.org/wiki/Gyrojet
http://en.wikipedia.org/wiki/Grenade_machine_gun

So we've got explosive rounds in the 25mm range with smart fusing and light armour penetrating ability, accurate rocket powered infantry weapons and crew served MGs firing large calibre shells. What are we missing, other than a real life need to put them all together (and the suspensors, of course, to allow one person to fire it easily)?

It's really interesting idea of building IRL Bolter, but please ,stick to the original question.

Thank you.

This is a really cool thread. I don't have much to contribute because I'm not going to pretend to know anything about engineering or weaponry, but the information exchange is very fun to read from you learned folk.

Ok i did some research.

the closest thing to a bolter is this:

http://www.youtube.com/watch?v=HoffTmg9bxU

Unlike the bolter it doesnt have anything to blow it out of the barrel, it goes straight to rocket mode, hence why the gun is covered in vents (as mentioned by me eralier), as a result the weapon is uses caseless rounds. Not terribly accurite. Not explosive, not fully automatic (It would have a very slow RoF), bullets cost more than the gun so not too many test have been done on them since the 60s.

That is the closest thing to a bolter. But to add the components like being guided, a shell, explosives and large caliber wouldnt work. Yet. What you see as the closest real world example is the inability to make it any more than a fancier bullet. No doubt this is where the CONCEPT of the heavy bolter came from (as i recall they used to be caseless) but as you can see there is a huge difference between the 2. The rounds needed would be huge and subsequently need bigger rockets so Personally id say its very very far off ever becoming a reality.

the main point i have and am making is the heavy bolter/bolter is just too small to be feasably made at that caliber and portability. It would end up like an artillery shell, just uselessly expensive.

The only way it could work is if you modify everything about the bolter (therefore no longer making a bolter) but then why do that when you have already got gun which the bolter kinda resembles (due to it being based of this weapon i think) but has been stretched and warped into some weapon that cannot exist. However cool sounding and looking.

I just read about an example of the US navy "firing advanced, gyro assisted, rocket proppelled shells" which is more like the bolter but as i said earlier, its an artillery peice.

http://en.wikipedia.org/wiki/Rocket-assisted_projectile (like many i try not to use wikipedia but sometimes its easier.)

The problem you're having. Swastakowey, is that you're ignoring 28,000 years of arms advancement between now and M30 when the Great Crusade kicks off. That length of time is nearly three times the length of time since Mankind first became a thing and today.

the main point i have and am making is the heavy bolter/bolter is just too small to be feasably made at that caliber and portability. It would end up like an artillery shell, just uselessly expensive.

But they did and can. It's a two-stage gyrojet mass-reactive explosive shell fired from a carbine-style assault weapon.

The heavy version is a bigger two-stage gyrojet mass-reactive explosive shell fired from a hip-aimed, or tripod-mounted, heavy-barrel weapon. It is not designed for one-man operation, unless that one man is a bioengineered super-soldier in a strength-enhancing, nuclear-powered armor-plated linear frame.

The bolter round hits you, its solid diamantine tip smashing through whatever excuse for armor you wear, triggering the microsecond delay of the explosive round until it's inside your body. The round then detonates, basically shattering, which leaves a hole in your chest the size of a man's fist (and probably also collapses both your lungs and shreds your heart. You're fethin' dead!)

Im talking about now dude. Who knows where things will be that far in the future, im not gonna even bother thinking about that haha. But right now the bolter is not possible. Not without so many changes that it no longer becomes a bolter. That was all my post was talking about.

We have explosive rounds. We have frangible rounds. We have armor piercing rounds.

A combination of explosive or frangible properties and the armor-piercing property (possibly through the use of a sabot round) would be the best to replicate a bolter.

Craft it in .30 and .50 cal. Make the .30 magazine fed and the .50 belt fed. Put the .30 in a rifle and the .50 in a modified Browning M2. Now you have a bolter and a heavy bolter.

 Psienesis wrote:
We have explosive rounds. We have frangible rounds. We have armor piercing rounds.

A combination of explosive or frangible properties and the armor-piercing property (possibly through the use of a sabot round) would be the best to replicate a bolter.

Craft it in .30 and .50 cal. Make the .30 magazine fed and the .50 belt fed. Put the .30 in a rifle and the .50 in a modified Browning M2. Now you have a bolter and a heavy bolter.

Yes but its not rocket propelled is it, nor is it the same caliber. So its a different weapon. There are weapons which share some properties of the bolter but no weapon that can have them all in one.