[Sangrun Hunter]

I decided to just hammer my barrel back into the trunion on my AMD 63 kit as a test.

First I measured the barrel and trunion to see what the difference was in size. Mine was less then .02, so a little polishing of the barrel and trunion with 320 then 400 grit paper. After the 400 everything looked real shiny and it was decided that was good enough instead of going to 600 then 2500.

I applied some anti-seaze paste to both parts then proceeded to hammer. The barrel went 2/3 of the way very easily using a rubber mallet with the trunion on a dense peice of Teak wood supported by the garage floor. That is where the taper starts to come into play to make it tougher.

The next step was a Brass hammer to send it home. At first the brass hammer did not distort or mar the barrel end, but the in the end it did, so take warning from my stupidty. Find a way to shield the threads on the end of the barrel with something, what that is I don't know yet.

I hammered the barrel in the rest of the way untill it was close to my measurement I took before removing the barrel. Then I made small adjustments and went too far which then needed a little adjusting the other way in the vise. I got it back in to my measurement which was too tight. Hmm? Okay, so I measeured my other AK's and AMD65 kit. It ended up working at the exact same measurement as the 65.

Btw: When you first start the barrel it's pretty easy to use a wrench to get the trunion and barrel timed with each other so the rear sight base will slip in with the trunion. You have to do this work in a vise! A big one is preferred with plenty of room.

I used a level to get the trunion and rear sight base on the same plane.

The vise was used to press the barrel pin back in after it was done in reverse order of what is posted in the library. Once I had the barrel in and headspace was working well I also noticed that the barrel pin hole was lined up perfect.


So, there ya' go. A hammer mechanic strikes again.

 

[7.62x39]

How about using a a old brake on the end of the barrel to protect the threads?
I'm sure most people have a brake lying around that was replaced by a US made part.

Even an old barrel nut or blank firing adapter could be used

 

[scubadvr]

Jeff, can you recrown the barrel? It is not a throw away is it? Jack

 

[Sangrun Hunter]

The barrel is fine and the crown is good too. It's just the threads for the muzzle brake that took a beating and I'm not worried at all. Some file work will clean it up good.

 

[hcpookie]

If you have no old/spare muzzle brake, buy one of those cheap muzzle nuts, that will protect the threads and can be cheaply discarded if you need to.

 

[Trust Me]

Here's what I did: I got two pieces of hard Maple 3/4" thick and about 6" by 6" and fit them to my vice to protect gun parts from the jaws. I routed a 1/2" groove horizontally into the wood, about 1/4" deep, and 90 degrees to the grain of the wood.
(Wood grain vertical, groove horizontal.) The AK barrels fit in there real nice, and the wood keeps the finish from getting damaged. If you start the trunion by hand, and properly index it, it should go on fairly easy.
I polished the barrel stub with 400 grit wet or dry (oil wet) cleaned it and then lubed the trunion and the barrel stub with case sizing, slipped the two parts together, indexed, and tapped the two parts together with a 32oz. ball peen hammer using a 1/2" thick strip of hardwood as a cushion between the hammer and the trunion legs. Monitor your progress by looking down into the cross pin hole. I've done three this way, and it has worked flawlessly (so far anyway).
A .30 caliber bore brush keeps the cross pin hole clear when you get close enough to run it through, and you should be able to get really close with moderate blows.
The advantage, as I see it, is that you work on the level and can see and feel exactly what you're doing, but of course, to each his own.
Another advantage is that the shock of the hammer blows is taken up by the barrel sides, not the muzzle end.

 

[yosuthnmasa]

I also left the barrel nut on, but put a hext bolt into the end of the barrel. I didn't want one that fit too tight, but big enough that I had a big enough surface to pound on. The bolt didn't scratch or mar the crown of the barrel either.

 

[leper]

i had a big chunk of 7075 i used when i wailed on mine with a hammer, i guess what ever works, works. used a press on the next one, it's lots easier