imported post
922r is the US Code. You MUST abide by that or suffer the consequences if caught violating them.
I bought a Yugo M59/66 SKS a few years ago that had a Kalifornia muzzle brake welded on. Since the lovely state of CA had its nasty mitts on it, I figured it was a good candidate for a bubba job.
I started with the Tapco T6 stock, which counted as three parts, the piston and follower (two more parts), Tapco magazine (three parts), removed the bayo and bayo "lug", removed the ladder sights for the 'nade launcher. This brought the count of US parts vsimport parts to the 922r requirement...hopefully. I also put a US made reciever cover on it with the picatinny rails for a reddot sight.