Make sure your SKS can take the aftermarket mags. I know the Norincos are quite versatile when it comes to accessorizing, but most others will not accept aftermarket anything without modifications to the gun. I know that there is a fixed 20 rounder that will take in a Norinco but they are probably a little rare these days. I HAVE seen them somewhere recently online, though. I have a Yugo so I can't do much. I don't believe in modifying war rifles anyway.
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