AK build question

[Camham]

Working on a M70AB2 kit tonight and after I removed the barrel assembly from the forward trunnion I noticed heavy scoring on the barrel aft of the barrel pin. I did not notice excessive resistance and some material came out with the forward trunnion but nowhere near the amount of material missing from the barrel though (material is to the right in the pics). Is this barrel unusable now and what the heck caused this? There is a small burr on the forward trunnion at the barrel pin hole but not enough to cause this and I would imagine the barrel is harder than the trunnion.

I tried to attach a picture, if it didn't work I'll try again.

Thanks for your help.

[kcstott]

Nope whole kit is now trash i buy it from you scrap value

I've seen worse barrels work just fine. A burr most likely caused it. Deburr the trunnion and try again.

[ott1]

Deburr the barrel pin hole in the trunnion before you press the barrel back. I've seen much worse galling on Yugo barrels.

[nicoroshi]

Yugos are notorious for galling on the way out.
In my experience it is because of the lower than standard AKM position barrel pin hole (and I have built a LOT of Yugos).
Trick to keep this from happening is to press the barrel forward about 1/4" after barrel pin is removed, and round the corner with a needle file through the barrel pin hole.
This takes time to do correctly and does not change where the barrel pin will hold the barrel for head space since you're only working the edge of the cut in the barrel.
Example of a Yugo barrel that I did this to before pressing out>>>


That being said I have seen Yugo barrels that are pretty galled up that function fine.
You should be alright.

[Gowking]

That being said if you don't like it you can get the barrel relieved where it is outside the cover of the trunnion. Similar to how Bulgarian barrels are done. You would have to depopulate the barrel and use a lathe to do this.

-MRA

[tujungatoes]

^^what they said. Build on brotha!

[Camham]

Thanks for your help guys. It is a really nice kit and it bumbed me out seeing the damage on the barrel but I will deburr and build on...

Have a great night and thanks again for your help.

Cam