Drill through your chamber while removing rivets?

[KrisFox 69]

After buying a CZ-52 pistol a few months back I've been hankering for a 7.62x25 AK.

 

A heavy blowback operated bolt and fed from PPSh-43 mags.

 

I figure since I have to chop a chunk of chamber off anyway and re cut for 7.62x25 I better not wast a perfectly good 7.62x39 barrel to do it. Especially since they can't be imported any more.

 

My idea is to cut the chamber off the ruined barrel, re-chamber, lathe a fitting to be pressed into the trunnion that includes a feed ramp, thread the inside of the fitting and the outside of the barrel to screw together then pin/weld the barrel to the fitting.

 

After that it's just a matter of making a proper magwell for the ppsh mags.

 

I want the mag to be in the rearward position so the mag release is in the proper location. This also means about 2 inches of barrel protrude INTO the receiver.

 

A 16" barrel that looks like a SBR 14"

 

Anyway if anyone has been hanging onto a barrel with a ruined chamber let me know.

 

If it works out really well I might be doing builds.

[Cobra 76 two 2,677]

Man are we ever gonna have some fun in the shop when you get home...

[vbrtrmn 167]

I've got an AK kit which is all f*ed up, the barrel should be fine, the barrel pin is partially drilled out. If you want the front-end or all of it, PM me.

[Cobra 76 two 2,677]

I've got an AK kit which is all f*ed up, the barrel should be fine, the barrel pin is partially drilled out. If you want the front-end or all of it, PM me.

 

PM sent!

[KrisFox 69]

I've got an AK kit which is all f*ed up, the barrel should be fine, the barrel pin is partially drilled out. If you want the front-end or all of it, PM me.

 

PM sent!

And so it begins.

[deadmilkman 0]

Check out the Vityaz SMG. I've been contemplating a blowback 7.62x25 myself. I've got a AMD kit all ready to sacrifice for the cause.

[MD_Willington 11]

If its not gas piston powered why not get a .30 cal (.310) blank and a 30 mauser reamer and contour & ream the blank?

Edited July 24, 2009 by MD_Willington

[Shandlanos 1,470]

Put me down on the list as interested! If you decide you're willing to do this for other people, I would love to have one and have an extra Romy G front half laying around.

 

Go for it!

[vbrtrmn 167]

KrisFox, your stuff will be going out on Monday to Cobra, I'm including the rear trunion & trigger guard as well as the gas tube. Don't really care about cash, just pay the favor forward to someone else

[KrisFox 69]

KrisFox, your stuff will be going out on Monday to Cobra, I'm including the rear trunion & trigger guard as well as the gas tube. Don't really care about cash, just pay the favor forward to someone else

 

I'll be sure too. Once I'm back I'll have to talk with Cobra76two. If we get enough free/cheap parts, and the project pans out, maybe we could donate it to a special member of the forum.

 

This might be the perfect AK for someone who is recoil sensitive and can't normally shoot.

[KrisFox 69]

If its not gas piston powered why not get a .30 cal (.310) blank and a 30 mauser reamer and contour & ream the blank?

 

I thought about doing a gas operated version.

 

What I ran into with my "thought experiment" was that I would have to shave a lot of weight off the bolt carrier group as well as shorten the gas system and open the gas ports.

 

Having a drop in blowback bolt assembly may also be a door to other pistol calibers... Or even a drop in .22 kit.

[elvis christ 451]

There was a dude over on theakforum.net that had built a x25 AK. Pretty much works like y'all are discussing. I think they were going to be selling kits for it soon.

[HillBilly2 9]

Just ran across this,thought y'all would be interested.....

 

http://www.ar15.com/forums/topic.html?b=4&...0262&page=1

[deadmilkman 0]

Interesting. I'm not going to buy one, but that is a great idea for making a bolt from scratch.

 

Thanks for the link!

 

Wes

[MD_Willington 11]

If its not gas piston powered why not get a .30 cal (.310) blank and a 30 mauser reamer and contour & ream the blank?

 

I thought about doing a gas operated version.

 

What I ran into with my "thought experiment" was that I would have to shave a lot of weight off the bolt carrier group as well as shorten the gas system and open the gas ports.

 

Having a drop in blowback bolt assembly may also be a door to other pistol calibers... Or even a drop in .22 kit.

 

 

I've seen them built both ways, I have never built one, only contemplated a bolt action carbine instead.

[RPK 3]

Your original idea won't work. I forgot the exact dimensional differences, but the bore needed for a x25 bullet is different from a x39 bore. Its either smaller or larger, point is you can't use a x39 barrel with x25 ammunition. That's not even considering the differences in case sizes, the x25 case is much different from a shortened x39 case. Therefore chopping off ~14mm off the chamber won't work either. I'd spend some money on a proper x25 barrel. Either a ppsh or pps barrel will work provided you legally extend it to 16" or get a tax stamp. I bought a 16" pps barrel from buymilsurp.com

 

There's also a lot more issues to deal with when building one. I wouldn't have undertook the project if I knew I couldn't do it. Even though I've never built an AK before, I was familiar with the action from my Saiga and I had a decent knowledge of tooling. I started with a AMD-65 kit, of which I used only half the parts, none of which were left unmodified. The trunnion was cut almost in half to make room for the magazine. The barrel was sleeved in 4 places (FSB, HG retainer, RSB and FT) since its diameter was overall smaller than a standard AK barrel. These sleeves were all turned on my lathe, don't expect to be able to do them by hand. The bolt and bolt carrier were milled in over 10 different places and both were shortened. The AK47 bolt required a bushing welded to the face to reduce its diameter for the smaller x25 case. A 74 bolt and carrier can be used, but they are expensive and hard to find. I couldn't do the welding (very small tolerances and I only have a 90amp mig) but luckily found someone who had experience in building x25 AK's that I shipped the parts to. He's currently rewelding my charging handle back on since my friend broke it off.

 

The bent flat was done in a vise and a hammer, torch and a big bar of steel. The ejector was moved a half inch forward and welding in place. Nearly an inch and a quarter was chopped off the front of the receiver. You can push the barrel in the trunnion farther, but I decided to do it this was. It doesn't matter which way you do it, the distance from the magazine to the barrel has to be shortened. Speaking of magazines, every other build I've seen online (yes there are 10+ of them that I've seen) has used the mag well portion of a PPs-43 lower receiver. I thought that was ugly sticking out of the bottom of the receiver, so I welded a tab on the rear of the magazine so it fit in the AMD mag catch. Then built up an internal magwell from aluminum. The front part of the magwell has a feed ramp. The distance from the magazine to the barrel on mine is roughly .5"

 

Finishing it from there was no problem. Most of the stuff I did is not necessary at all. I built mine in a more practical way, so I changed a lot. The front sight was chopped in half and welded to the gas block. The rear sight is from a G3 and is screwed to the top cover. The top cover remains zeroed because its hinged at the RSB like a krink. A fixed stock rear trunnion was riveted in place to comply with CT's AWB.

 

I'm not trying to discourage anyone from building one, it was an overall fun build looking back, though frustrating at times. The end result was very worth it. You just have to know what you're getting yourself into before you invest in the parts. I still have some more work to do, like converting more magazines and getting the gun to cycle reliably (its at 75% right now, up from 50% the first time I shot it.)