Belt fed 7.62x39 SMG

[Tribal]

Any ideas how could one make a belt fed SMG? I am just interested... How can that be made, it would surely increase bullet capacity and with a 7.62x39mm it would rather be a mashinegun (just a little toy for self-defence, against armies).

[festergrump]

Here's the general idea of how they work:

http://science.howstuffworks.com/machine-gun10.htm

I never was interested in making one, myself. A double stack magazine system seems by far easier to make, get to feed properly, and from what I can guess: more reliable. They also can hold a good bit of ammo. Look into a weapon which can accept a drum...

[Third_Rail]

Being where you are, it would be easier to obtain an AK magazine and go from there. A homemade rifle/subgun using that would be a whole lot simpler than trying to build a belt-fed from scratch.

[Third_Rail]

Being where you are, it would be easier to obtain an AK magazine and go from there. A homemade rifle/subgun using that would be a whole lot simpler than trying to build a belt-fed from scratch.

[Third_Rail]

Being where you are, it would be easier to obtain an AK magazine and go from there. A homemade rifle/subgun using that would be a whole lot simpler than trying to build a belt-fed from scratch.

[malzraa]

Um, do you mean LMG, bacause I thought SMG's fired pistol ammunition? Maybe I am mistaken.
Why don't you just get/make drum magazines? They can hold 100+ rounds, and are less jam prone.

[malzraa]

Um, do you mean LMG, bacause I thought SMG's fired pistol ammunition? Maybe I am mistaken.
Why don't you just get/make drum magazines? They can hold 100+ rounds, and are less jam prone.

[malzraa]

Um, do you mean LMG, bacause I thought SMG's fired pistol ammunition? Maybe I am mistaken.
Why don't you just get/make drum magazines? They can hold 100+ rounds, and are less jam prone.

[Jacks Complete]

The distinction isn't between LMG and SMG like that, it is more to do with the size of the gun than the cartridge. An SMG is supposed to be very small, so they tend to be built around smaller cartridges, like 9mm or 5.7x28. But you can't argue that 5.7x28 isn't what would traditionally be a rifle cartridge. And this is even more true of the tiny 4.7x30.

A belt-fed weapon is way cooler than a drum, and you can fire a thousand rounds or more. In fact, you can keep going until the barrel melts off. Not the typical role for an SMG, but there you go.

However, wire it to one of these tanks http://www.iwantoneofthose.com/BAT2TA_TOYS.htm or even better, one of these http://www.iwantoneofthose.com/ROODEF_TOYS.htm and you have a sentry gun or mobile kiling machine. In fact, I'm going to start a new thread on just such a topic.

[Jacks Complete]

The distinction isn't between LMG and SMG like that, it is more to do with the size of the gun than the cartridge. An SMG is supposed to be very small, so they tend to be built around smaller cartridges, like 9mm or 5.7x28. But you can't argue that 5.7x28 isn't what would traditionally be a rifle cartridge. And this is even more true of the tiny 4.7x30.

A belt-fed weapon is way cooler than a drum, and you can fire a thousand rounds or more. In fact, you can keep going until the barrel melts off. Not the typical role for an SMG, but there you go.

However, wire it to one of these tanks http://www.iwantoneofthose.com/BAT2TA_TOYS.htm or even better, one of these http://www.iwantoneofthose.com/ROODEF_TOYS.htm and you have a sentry gun or mobile kiling machine. In fact, I'm going to start a new thread on just such a topic.

[Jacks Complete]

The distinction isn't between LMG and SMG like that, it is more to do with the size of the gun than the cartridge. An SMG is supposed to be very small, so they tend to be built around smaller cartridges, like 9mm or 5.7x28. But you can't argue that 5.7x28 isn't what would traditionally be a rifle cartridge. And this is even more true of the tiny 4.7x30.

A belt-fed weapon is way cooler than a drum, and you can fire a thousand rounds or more. In fact, you can keep going until the barrel melts off. Not the typical role for an SMG, but there you go.

However, wire it to one of these tanks http://www.iwantoneofthose.com/BAT2TA_TOYS.htm or even better, one of these http://www.iwantoneofthose.com/ROODEF_TOYS.htm and you have a sentry gun or mobile kiling machine. In fact, I'm going to start a new thread on just such a topic.

[Tribal]

There was SMG in 5.56mm - german manufacture (H&K) experimental... I think that an SMG is a gun for close quarters firearm, just like shotgun (SMG-fast firing, compact) this isn't to shotgug, but SMG (shotgun is powerful, sometimes compact, but mostly not)... You can alway's use water cooled barrels and could be fine to use an electrically cooled (with several electrical fans) it would be simplier to build it this way, than making a minigun. Might make the barrels life longer, what do you think?

[Tribal]

There was SMG in 5.56mm - german manufacture (H&K) experimental... I think that an SMG is a gun for close quarters firearm, just like shotgun (SMG-fast firing, compact) this isn't to shotgug, but SMG (shotgun is powerful, sometimes compact, but mostly not)... You can alway's use water cooled barrels and could be fine to use an electrically cooled (with several electrical fans) it would be simplier to build it this way, than making a minigun. Might make the barrels life longer, what do you think?

[Tribal]

There was SMG in 5.56mm - german manufacture (H&K) experimental... I think that an SMG is a gun for close quarters firearm, just like shotgun (SMG-fast firing, compact) this isn't to shotgug, but SMG (shotgun is powerful, sometimes compact, but mostly not)... You can alway's use water cooled barrels and could be fine to use an electrically cooled (with several electrical fans) it would be simplier to build it this way, than making a minigun. Might make the barrels life longer, what do you think?

[Third_Rail]

I think that the H&K belt fed SMG was actually in .308, if memory serves. I'm going to look it up.

EDIT: I can't even find it now... maybe it was .223, I can't check. :o

[Third_Rail]

I think that the H&K belt fed SMG was actually in .308, if memory serves. I'm going to look it up.

EDIT: I can't even find it now... maybe it was .223, I can't check. :o

[Third_Rail]

I think that the H&K belt fed SMG was actually in .308, if memory serves. I'm going to look it up.

EDIT: I can't even find it now... maybe it was .223, I can't check. :o

[Jacks Complete]

Off the top of my head, I know that H&K did make a .223 version of some of the smaller SMGs.

Water cooled barrels and Peltier effect coolers are a bit of a faff. Peltiers aren't very powerful and need loads of current. I would go for something like a phase change material, or just a cooling fan or heat sink. How many rounds can you fire at high rates before the inside of the barrel gets far to hot, while the outside stays cool, and it melts or explodes anyway? You have to slow the rate of fire to something reasonable, like two or three rounds a second, if you don't want to melt the entire gun after a few hundred rounds of full auto, unless it was designed for that kind of abuse.

[Jacks Complete]

Off the top of my head, I know that H&K did make a .223 version of some of the smaller SMGs.

Water cooled barrels and Peltier effect coolers are a bit of a faff. Peltiers aren't very powerful and need loads of current. I would go for something like a phase change material, or just a cooling fan or heat sink. How many rounds can you fire at high rates before the inside of the barrel gets far to hot, while the outside stays cool, and it melts or explodes anyway? You have to slow the rate of fire to something reasonable, like two or three rounds a second, if you don't want to melt the entire gun after a few hundred rounds of full auto, unless it was designed for that kind of abuse.

[Jacks Complete]

Off the top of my head, I know that H&K did make a .223 version of some of the smaller SMGs.

Water cooled barrels and Peltier effect coolers are a bit of a faff. Peltiers aren't very powerful and need loads of current. I would go for something like a phase change material, or just a cooling fan or heat sink. How many rounds can you fire at high rates before the inside of the barrel gets far to hot, while the outside stays cool, and it melts or explodes anyway? You have to slow the rate of fire to something reasonable, like two or three rounds a second, if you don't want to melt the entire gun after a few hundred rounds of full auto, unless it was designed for that kind of abuse.

[charger]

Third Rail, I think the gun you are talking about is a version of the HK21, I read somewhere that only a couple of these were ever made. It was made in 308, but i think there was a 223 version as well.

[charger]

Third Rail, I think the gun you are talking about is a version of the HK21, I read somewhere that only a couple of these were ever made. It was made in 308, but i think there was a 223 version as well.

[charger]

Third Rail, I think the gun you are talking about is a version of the HK21, I read somewhere that only a couple of these were ever made. It was made in 308, but i think there was a 223 version as well.

[Tribal]

Listen, how could I make a gun that would shoot that slow, it would be really nessesary, becouse i don't want to pull the trigger and realize, that the magazine is empty...
I've always admired the slow mashine guns, what you can shoot and shoot ...

[Tribal]

Listen, how could I make a gun that would shoot that slow, it would be really nessesary, becouse i don't want to pull the trigger and realize, that the magazine is empty...
I've always admired the slow mashine guns, what you can shoot and shoot ...

[Tribal]

Listen, how could I make a gun that would shoot that slow, it would be really nessesary, becouse i don't want to pull the trigger and realize, that the magazine is empty...
I've always admired the slow mashine guns, what you can shoot and shoot ...

[Third_Rail]

Heavier bolt, delayed unlocking, etc. There are a number of ways to slow things down.

[Third_Rail]

Heavier bolt, delayed unlocking, etc. There are a number of ways to slow things down.

[Third_Rail]

Heavier bolt, delayed unlocking, etc. There are a number of ways to slow things down.

[tomu]

Unfortunately slowing down a full automatic weapon to such a slow rate of firing, especially a Machine Gun firing high powered rifle ammo is not that simple.

Mechanical devices that considerably slow down machine guns make them bulky and awkward to handle.

Some SMG's (mind you they use pistol ammo) as the Astra 900 (Mauser C 96 look-a-like) and the some Stechkin pistols have a mechanical device that slows the firing down from over a thousand to some hundred shots per minute. But these mechanical devices aren't trivial and are always prone to damage.

One of the things soldiers learn is that full auto weapons are only burst fired. Only short consecutive burst are fired from a full auto weapon and never ever is the whole belt or mag fired in one single burst. The military is very keen on firing discipline.

Anyway building a machine gun with or without belt-feed isn't trivial or can be achieved with common tools. One needs a thorough understanding of metal working and engineering and a full equiped tool shop (e.g. lathe, milling machine, drill press, complete with tools and jigs, heat treating furnace etc.) and proficient skills to use it as well.

A SMG like the STEN or the Luty can be build with simple tools, basic knowledge and average skills. It would be a good beginners project to build one of these SMG's.

I found these two pics of a HK G3 showing a bulged barrel after 1.000 shots were fired full automatically through it, total shots fired from that rifle were 81.200 during an endurance test.

[tomu]

Unfortunately slowing down a full automatic weapon to such a slow rate of firing, especially a Machine Gun firing high powered rifle ammo is not that simple.

Mechanical devices that considerably slow down machine guns make them bulky and awkward to handle.

Some SMG's (mind you they use pistol ammo) as the Astra 900 (Mauser C 96 look-a-like) and the some Stechkin pistols have a mechanical device that slows the firing down from over a thousand to some hundred shots per minute. But these mechanical devices aren't trivial and are always prone to damage.

One of the things soldiers learn is that full auto weapons are only burst fired. Only short consecutive burst are fired from a full auto weapon and never ever is the whole belt or mag fired in one single burst. The military is very keen on firing discipline.

Anyway building a machine gun with or without belt-feed isn't trivial or can be achieved with common tools. One needs a thorough understanding of metal working and engineering and a full equiped tool shop (e.g. lathe, milling machine, drill press, complete with tools and jigs, heat treating furnace etc.) and proficient skills to use it as well.

A SMG like the STEN or the Luty can be build with simple tools, basic knowledge and average skills. It would be a good beginners project to build one of these SMG's.

I found these two pics of a HK G3 showing a bulged barrel after 1.000 shots were fired full automatically through it, total shots fired from that rifle were 81.200 during an endurance test.

[tomu]

Unfortunately slowing down a full automatic weapon to such a slow rate of firing, especially a Machine Gun firing high powered rifle ammo is not that simple.

Mechanical devices that considerably slow down machine guns make them bulky and awkward to handle.

Some SMG's (mind you they use pistol ammo) as the Astra 900 (Mauser C 96 look-a-like) and the some Stechkin pistols have a mechanical device that slows the firing down from over a thousand to some hundred shots per minute. But these mechanical devices aren't trivial and are always prone to damage.

One of the things soldiers learn is that full auto weapons are only burst fired. Only short consecutive burst are fired from a full auto weapon and never ever is the whole belt or mag fired in one single burst. The military is very keen on firing discipline.

Anyway building a machine gun with or without belt-feed isn't trivial or can be achieved with common tools. One needs a thorough understanding of metal working and engineering and a full equiped tool shop (e.g. lathe, milling machine, drill press, complete with tools and jigs, heat treating furnace etc.) and proficient skills to use it as well.

A SMG like the STEN or the Luty can be build with simple tools, basic knowledge and average skills. It would be a good beginners project to build one of these SMG's.

I found these two pics of a HK G3 showing a bulged barrel after 1.000 shots were fired full automatically through it, total shots fired from that rifle were 81.200 during an endurance test.

[MightyQuinn®]

The best way to slow down a full-auto is trigger control. Rely on the human to determine ROF (rate of fire.)

It's easy to consistently fire 2-3 round bursts using a full-auto. Very effective in countering muzzle rise as well.

Double-stack the mags to carny more ammo at the ready.

[MightyQuinn®]

The best way to slow down a full-auto is trigger control. Rely on the human to determine ROF (rate of fire.)

It's easy to consistently fire 2-3 round bursts using a full-auto. Very effective in countering muzzle rise as well.

Double-stack the mags to carny more ammo at the ready.

[MightyQuinn®]

The best way to slow down a full-auto is trigger control. Rely on the human to determine ROF (rate of fire.)

It's easy to consistently fire 2-3 round bursts using a full-auto. Very effective in countering muzzle rise as well.

Double-stack the mags to carny more ammo at the ready.

[tiac03]

Cool site I stumbled upon a few days ago had some nice high quality videos of different weapons being fired. one was the Shrike conversion for the ar-15. Upper reciever, heavier barrel, and a bolt. converted the Ar15 into a belt fed version.

The site is www.subgunvideos.com
The vids of the shrike system are here: http://www.subgunvideos.com/videos/Rob%20Silvers%20Videos/Shrike%20Videos/

The reason I posted this is because part one shows the weapon and actually shows nice high quality pics of the feeding mechanism. Looks alot like the M249's, so it should help you out.
(second vid is for those who want to see someone firing some ammo through it... )

[tiac03]

Cool site I stumbled upon a few days ago had some nice high quality videos of different weapons being fired. one was the Shrike conversion for the ar-15. Upper reciever, heavier barrel, and a bolt. converted the Ar15 into a belt fed version.

The site is www.subgunvideos.com
The vids of the shrike system are here: http://www.subgunvideos.com/videos/Rob%20Silvers%20Videos/Shrike%20Videos/

The reason I posted this is because part one shows the weapon and actually shows nice high quality pics of the feeding mechanism. Looks alot like the M249's, so it should help you out.
(second vid is for those who want to see someone firing some ammo through it... )

[tiac03]

Cool site I stumbled upon a few days ago had some nice high quality videos of different weapons being fired. one was the Shrike conversion for the ar-15. Upper reciever, heavier barrel, and a bolt. converted the Ar15 into a belt fed version.

The site is www.subgunvideos.com
The vids of the shrike system are here: http://www.subgunvideos.com/videos/Rob%20Silvers%20Videos/Shrike%20Videos/

The reason I posted this is because part one shows the weapon and actually shows nice high quality pics of the feeding mechanism. Looks alot like the M249's, so it should help you out.
(second vid is for those who want to see someone firing some ammo through it... )

[Tribal]

Hey, what RPM has "PA Luty" have? I think that they are really fast, becouse of the simplicity of bolt, but I dunno. Something about 800 rpm?

And I'm thinking that a double stack magazine or a drum magazine would be more usable, First got to make a barrel for my 7.62x25mm SMG.
Hey, would it look like this? Being made from highest quality tool steel...

[Tribal]

Hey, what RPM has "PA Luty" have? I think that they are really fast, becouse of the simplicity of bolt, but I dunno. Something about 800 rpm?

And I'm thinking that a double stack magazine or a drum magazine would be more usable, First got to make a barrel for my 7.62x25mm SMG.
Hey, would it look like this? Being made from highest quality tool steel...

[Tribal]

Hey, what RPM has "PA Luty" have? I think that they are really fast, becouse of the simplicity of bolt, but I dunno. Something about 800 rpm?

And I'm thinking that a double stack magazine or a drum magazine would be more usable, First got to make a barrel for my 7.62x25mm SMG.
Hey, would it look like this? Being made from highest quality tool steel...

[armchairsapper]

Here is a homemade beltfed 7.62x39. It is a mix of MG42, AK47, and other parts. http://www.gunco.net/forums/f50/mg47es-belt-feed-37756/

[armchairsapper]

I think that the H&K belt fed SMG was actually in .308, if memory serves. I'm going to look it up.

EDIT: I can't even find it now... maybe it was .223, I can't check. :o

It was a HK51B. Here's a pic of an HK21 & HK51B.

[crazywhiteguy]

You could take the expedient home made BPS SMG and make it fire from a hopper full of ammo. But firing from a belt is a complex mechanism that wouldn't be worth the effort for a home made toy.

[armchairsapper]

You could take the expedient home made BPS SMG and make it fire from a hopper full of ammo. But firing from a belt is a complex mechanism that wouldn't be worth the effort for a home made toy.


This particular one is not mine, however, I have made a few belt fed guns and know MANY people who have made their own. The one in the pic is quite reliable & rugged. Hardly a toy. The feed tray & cover are from an MG42 which can be purchased for about $50.

Why would I want make it fire from a hopper? It feeds great with links/belts! Guns that fire from a hopper are notoriously unreliable; jamming frequently. Making a feed cover/tray would indeed be hard (about as hard as making a barrel). Which is why homebuilders buy those parts.

[paul88]

Instead of an actuating arm why not a "circle" that does that exact same thing but gets pulled by the backwards stroke of the bolt, cutting down the weight and bulky ness?

[armchairsapper]

I'm not quite sure what you mean. The pic is of the top cover of my MG42 (the same feed cover as the belt fed in the previous pic). The arrow points to the channel that the bolt travels in which is what causes the links to feed.

[paul88]

Well doing some figuring and such a "wheel" wont work, But i do have another idea that is small and could be just as effective (you could fit it in luty's MP) But i need a picture of the typical grabber deal. I keep forgetting the name of that part that actuall grabs the links and pulls them through, if someone could get me a good picture of one that would be great.
Is it like a hook or somethen?
When i get a picture i can make a prototype and let yall know how it works

[armchairsapper]

The two pics are of the feed mechanism. The first shows the two "claws" before the they are actuated. The 2nd shows the claws as they would be when feeding the next round. The one in the center, with the arrow, folds up to allow the next round to progress forward. I hope this helps you with your design.

[paul88]

it does thanks for the pics

[Cutaway]

A belt-fed 7.62x39mm "SMG" would not be a SMG because it would fire rifle rounds. It would be a belt fed carbine.

7.62x51mm NATO belt links will fit around .45ACP rounds which could make a belt-fed submachine gun:cool:

[rudyak]

Pistol rounds might not provide enough 'oomph' to feed reliably.

I can't access the pictures as I don't have enough posts or something, but the HK51 is a short (8 inch) barreled rifle. Several were belt feed. The muzzle flash was the size of a volkswagen, and drawfed the flash from a .50!

At one time or another, all HK rifles were offered in a beltfed, select fire version.

You can slow down the beltfed, rifle calibers by increasing the weight of the bolt, using a weaker spring, or by lengthening the travel of the bolt.

Increasing the weight of the bolt is usually used in Submachine guns where size is an important consideration. Remember sub guns fire a pistol round and usually fire from an open bolt using delayed primer ignition.

Legthening the distance that the bolt is required to travel is used in true machineguns firing a rifle cartrige. They usually fire from an open bolt, but use a locked bolt for ignition. The bolt is at rest at the rear portion of it's travel to aid in cooling and prevent cook-off rounds. problems arise with long travel when undercharged or weaker ammunition is used. The recoil might be less than required for the sear to engage the bolt in it's resting or rear most position, there by causing a "run-a-way" gun.

Weaker springs can cause problems with feeding as there might not be enough force to strip a round from the belt and reliably feed it into the chamber.

Hope this helps.

[Wallybanger]

No need to re-invent the wheel. The RPD is belt fed in 7.62x39 and has been around since the end of the second world war.

http://en.wikipedia.org/wiki/RPD_(weapon)