Bought chinese version, no gas selector or tube sights. Pretty gummed up with the cosmoline, I dont think original owner(s) ever cleaned it. dismantled,Rinsed it with gasoline, oiled with hoppers 9, came with ~800 rnds of copper looking shelled ammo(he said they were military surplus?) in the 10 stripper clips. Randomly the bullets would either become parrellel in the internal mag and stop loading or the tip would not get lifted inline with the chamber and would get stuck in the corner. Would this be due to the military surplus rounds? or is the spring in the mag just wore out and needs replacing? part 2 I was thinking of getting a tapco t6 stock and was wondering if it will accomidate an extended removable mag as well? most say you have to modify the mag port opening on the original stocks to acc. the mag release.