There's a chance that the chamber was damaged due to the barrel stopping on the link. Since you mentioned that your pistol was a frankengun, that's a distinct possibility. I've seen a chamber crack in a sort of "U" shape from that, and had it not been caught, would have probably let go within another couple hundred rounds. To be on the safe side, check your new barrel as follows: Assemble the gun with the slidestop arm hanging vertically. Push the muzzle straight back against the edge of a heavy bench or a doorframe until it stops dead and hold it firmly. See if the slidestop arm will swing freely. It should. If it gets into a bind, the barrel is stopping on the link and at the very least will break the link at some point. This can also pull the lower lug off the barrel, or cause a crack at the chamber.