Gunco Forums banner

belt feed ak-47

130K views 770 replies 90 participants last post by  Warwickben 
#1 ·
I just recentlly finished a beltfeed ak-47 base fire arm with a scratch built receiver, a MG-3 top cover/belt feed mechanism, FAL fcg, scratch built stock, grip frame & grips and forearm, k98 rear sight and m60 return spring. You can see photos of it on PHOTOBUCKET, search for 300 WSM FAL or SHARPSSHOOTER5090.
 
#29 ·
300WSM FAL details,
The receiver is made from a Centry casting that has a 3 lug forward lock up barrel extension welded to the casting , machined and then re-heatreated. The bolt is a Winchester model 100 3 locking lug bolt fitted to a modified FAL bolt carrier. The barrel is a heavy Winchester 26" model 70 SS target barrel. The front handguard is free floating, mounted off of the barrel extension. The muzzle brake is a SS unit made by myself also.
 
#31 ·
Hey SS I had a thought - I remember someone, and I think it was Kevin_M4, who had a loose gas block on their Saiga conversion, and silver soldered it onto the barrel. That may be a quick-and-dirty way to help your loose gas block issue.

The fact that it bleeds gas around the port will definitely cause lower barrel velocity, obviously resulting in less energy to cycle the weapon.

Another thought, and I learned this from my MG42 build, and that is to degrease everything, use a sharpie or two and cover all the moving parts in black, and cycle the action by hand. The chafe marks are where rubbing is taking place, and in theory there should be very few places that rub. I found several areas that rub using this method. The areas were small, and I ignored them until I polished them one by one, and the net effect was a smoother action.

Hopefully this helps out. The piston size should still be considered as a to-do item, but if you do these things first it may not matter.
 
#32 ·
Leaking gas block

Hcpookie,
The gas leak I had was between the gas block and the gas tube not between the gas block and barrel. That is still a press fit and gas tight. Last week end I bored out the end of my gas tube and soldered in a brass bushing. I machined out the I.D. of the bushing to be a zero clearace to the gas block nose. I now requires a few taps from a hammer to get the gas tube in place. That should stop the gas leak there. Ther other thing I did was remove the L1A1 flash hider and built a Krinkov style booster/gas accumulator to hold the gas pressure up a little longer. I also bought a yugo rpk barrel which is about 4" longer that the standard AK barrel and am going to install that along with the Krinkov booster/flashhider cone. Hopefully I can try it this week and will post the results.
I may need to install a roller on the hammer cocking hump on the bolt carrier as there is some resistance when the hammer is pushed to the re-cocking position as the bolt carrier rides over the hammer.

Thanks for the advice. Any advice is welcome.

Sharpsshooter5090
 
#33 · (Edited)
Belt feed ak-47 update

I just received a Yugo RPK barrel and gas block that I might put on my beltfeed. This barrel is 21 inches v.s. 16 inches of the standard Romey Ak-47 barrel. Hopefully the longer barrel will keep the gas pressure up enough to reliabally cycle the bolt carrier all the way back every time. I built and installed a Krikov style booster and tightened up the joint between the gas block and gas tube but have not had a chance to try it. I took it to the range to test but somebody was shooting a 50 BMG with API bullets and caught the dry grass at the range on fire and they closed it before I had a chance to try the modifications. Since then I also installed a roller on the bolt carrier to so the hammer rolls over it to cock instead for sliding on steel to steel. Back to the range to try it as soon as I get a chance. I hope I don't have to put on the RPK barrel as it means that it will esentially will not be a belt feed Ak-47 but a home made RPK. That's OK but I started the project out to see if a beltfeed could be made based on cheap AK-47 parts. (Although the fat RPK barrel will look a lot better than the skinny AK-47 barrel.)

I will post the results as soon as I get some.

Sharpsshooter5090
 
#36 · (Edited)
MG-47 RECENT MODS

I will try to take some pictures of the recent mod's as soon as I get some time. Hope to try them out this week end. My time has been taken by building this long range target/tactical rifle for my son. It has a scratch built 3 locking lug action, a Timeny adjustable trigger, 03A3 firing part, a Bell & Carson butt stock and a scratch built steel stock from the butt stock forward. I have haven't had a chance to build a muzzle brake for it yet.
 

Attachments

#38 ·
My mg-47 beltfeed ak works great now. Tightening up the gas tube to gas block seems to solved the problem. It works with and with out the Krinkov style gas booster. With the booster, the bolt carrier moves back so fast that it started to push the return spring out the back of the butt stock. I made a recoil buffer with a bolt stop that is pinned to the receiver . That should stop that problem. Attach is a short camera phone video is .zip format. I will take more pictures of the details and post them asap.
 

Attachments

#45 ·
BELTFEED TRUNNION

I will have to take the thing apart and take some good photo's. I didn't have to take any thing off the trunnion. I cut the top out of the square tubing off but left enough material to fucntion as the top bolt guide rails similar to the bent over top on a std. ak receiver. I then welded another piece back on the top to cover the trunnion. There is a photo of the back of the receiver on Photobucket. Search under "Sharpsshooter5090" for some photos of the receiver
 
#46 ·
I finally saw the video...

I had the QT alternative codec and until I installed the "real" QT codec it wouldn't play.

That seems to have quite a bit of recoil! Does it kick you off target at all? I was thinking about how to reduce the recoil and other than a muzzle brake I'm not sure what else you could do.
 
#47 ·
AK-47 beltfeed

It does have a surprising amount of recoil for a 14 lb 7.62x39. I attribute that not to true bullet recoil but to the bolt & bolt carrier hitting the bolt stop. I need to make a more effective buffer than just a 1/8" piece of rubber. Maybe a spring setup. One other option is to make the gas block regulatable like a FAL. Before I sealed up all the gas leaks the bolt would not go back with enough force to reliably cycle the belt feed mechanism, now it is almost to much. And yes, it does throw you off target somewhat but then again so does a MG-42.
One other thing I have to change is to raise both the front and rear sights. They are just to low to re-aquire in a hurry.
 
#49 ·
SHARPSSHOOTER5090 said:
And yes, it does throw you off target somewhat but then again so does a MG-42.
Not mine! My .308 is surprisingly stable for rapid firing. Perhaps 8mm is hotter, but at least in .308 it doesn't keck any more than my RPK. My G3 kicks worse than the MG42.
 
#51 ·
AK-47 BELTFEED PROJECT

HC.

You know even thought is does appear to have a fair amount of recoil, it makes it that much more fun to shoot. More like a more powerful MG than a something that shoots the small 7.62x39 cartridge. That's one reason why I built it, that big gun feel with out the higher cost of 7.62x51 or 8mm ammo plus to see if I could really make a beltfeed out of AK parts.

Next project, is make a beltfeed FAL. And yes, the receiver side rails will have to be reinforced but when you start with a rough casting I can modify it as required to make it strong enough. As a Mechanical engineer, I can and will calculate the receiver side rail stresses and beef it up as required.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top