I have a Arsenal SGL-21. Recently I bought a second hand Siaga operating rod and bolt just to keep for spare parts given the potential for a ban. I put it away and never though a thing about it. I took my Arsenal up to my cabin and did a little shooting and brought it home and cleaned it. I noticed that the operating rod that came with the gun has slop in it and can be wiggled around easily. That begged the question, what was the other rod like that I bought second hand. Its solid as a rock and you couldn't wiggle it no matter what? Its some slop in a operating rod normal for AK style weapons? When I say operating rod I'm referring to the piston that screws into the bolt carrier.