Parts kit and 80% receiver blank (yes, the build was a rather major pain)
There are a few things I have suspicions about as far as my M76; like many of these 'new unissued' milsurp demils, I suspect they never ran in the first place, or at least weren't tested. My reasoning is because the upper hand guard basically didn't fit the rear sight base, causing the gas tube to both bind on the underside of the carrier and making the takedown lever nearly impossible to turn. The whole kit is numbers-matching down the demilled receiver and scope. I've found such odd inconsistencies on a couple 'new condition' demilled parts kits, which makes me wonder if they were essentially factory-seconds, or if workers were simply passing off defective stuff to make quotas (I suspect the latter's a bullseye).
At any rate, they did a better job than ORF, since the shredded receiver remnants I had were far better machined, especially internally. ORF used worn cutters for everything, so there's lots of tapers and radiuses where there shouldn't be, and the parts had to be relieved to fit (and the bolt lugs had to be lapped extensively, as only 1/8 of their bearing surface was engaged). Almost there, though I still have to tweek my US-made disconnector so the hammer won't follow (mods to the hammer have been needed, as I think the FCG pivot holes where placed too high on the receiver, and now it doesn't get pressed down quite far enough to snag the disco, so the hooks need to be filed back about .01")
TCB
The M76 is a nice shooter, though not the most reliable. I'm still getting the bugs worked out of mine, though they are more the fault of Ohio Rapid Fire than the Slavs. MG15 30 rounders can be modded to work, too, btw.