To build a semiautomatic AK-47, the problem isn't that you need to replace specific parts with USA made parts... the problem is you can not have more then 10 imported parts.
The folowing thread has information about which parts are affected and more info:
http://www.quarterbore.net/forums/showthread.php?t=159
With a stamped kit, you need to replace six USA made parts. The six parts you must replace are six of the following:
(1) Frames, receivers, receiver castings, forgings or stampings
(2) Barrels
(3) Mounting blocks (trunions)
(4) Muzzle attachments
(5) Bolts
(6) Bolt carriers
(7) Gas pistons
(8) Triggers
(9) Hammers
(10) Disconnectors
(11) Buttstocks
(12) Pistol grips
(13) Forearm handguards
(14) Magazine body
(15) Followers
(16) Floorplates
So, most people use a US receiver, piston, and Trigger, Hammer, Disconnect, and pistol grip... these parts are most commonly replaced because they are reasonably cheap and quality US made parts are easy to get... Just the same, you can replace any six of these parts and you will be 922(r) compliant.
As for making your own parts, I doubt you can make them for what they cost to buy and as for modifying imported parts to make them USA made, well that just likewise sounds like too much hastle that leaves risks over a very small cash savings...
Hope this helps some!
QB
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