Your are correct on the compliance parts. Im not sure about the 74 brake
So far the only US marked part I found is the block that the grip screw goes into.
The trigger is marked "025"; likely foreign since typically Century put in a tapco G2.
Looks like I'll need 6 compliance parts unless something turns up on the brake or gas piston.
I'm not sure how common this was but it has an upturned bolt handle; it is kind of rough so I'm unsure whether it came out of the factory that way or was a home project.
Stupid question: if this was originally imported in the single stack configuration would it have needed any compliance parts at that time?
On century guns if it is not marked with u.s. or usa then it will have a little c on it for the compliance parts. Such as gas piston or muzzle device etc. And in original single stack form I don't believe they need 922 parts. However I could be mistaken. Now if century did the double stack conversion then it should have the nessisary compliance parts already installed. Century does this themselves. Now if someone did the conversion themselves then you should def make sure it has the correct parts.
I finally got around to taking some pictures:
Inside the lower hand guard.
I'm not positive but I think the fsb is bulgarian? How about the brake?
This was soaked for 2 days in Hoppes#9 but still doesn't come off; any suggestions?
The threads are bunged up a bit; measure around .54" is that enough for 14/1 LH? With the brake on it is a little loose; however I don't think it is the barrel threads alone causing this but a stackup of tolerances on the barrel threads, the adapter and the brake itself.