Building an AK on an AMD parts kit using a US barrel (caliber conversion). One little problem though. The barrel got turned a wee bit too small. It slides in and out by hand. Need a new lathe, the one that did it's pretty shaky. But what to do with what I have is the question. Was thinking of using a Chinese trunion, assuming the AMDs are 23mm and the Chinese 19mm. Or would a 22mm AK-74 one work with the existing AMD bolt?

Next, how the heck does one set headspace on an AK? I mean, you can't exactly turn the thing in a fraction of a turn at a time knowing the thread pitch. Do you put a headspace gage in there and then tighten on top of it?

And if an AK is out of headspace, ie NO-GO, do you have no recourse but to chuck the barrel, or is there a way to build up material on the bolt face?

I've read oodles of tutorials on how to CHECK headspace on an AK. But nothing on how to SET headspace.

Note that this project is not high precision. I'm not expecting any level of accuracy out of it. But it has to be safe to shoot.

the head space is set but the bolt to trunion contact, in relation to the shoulder in the chamber. building up the face of the barrel would not work. do basicly what you said ... intsall a go gauge, close the bolt up and push the barrel in till it stops. then you repin it.

as for the loose fit of barrel to truinion there are a few ways to correct it, one would be too drill and tap the trunion then screw in an insert that fit the barrel properly. or you can knurl it to tighten it

IIRC, Pookie has done the knurling with good results.