This has been around before so humor me a little. Purchased a new contender G2 carbine barrel that is loose on the frame with mostly side to side movement. I thought it might be this specific barrel so I tried another one that a friend had with the same results. None of my 21" old style carbine barrels are loose, any thoughts on this? I know about Bellms oversized pins but I don't want to go that route. Does anyone make an expandable pin that is adjustable? thanks, T