RickB· Super Moderator
EDC: SIG P938.
The barrel lower lugs, forward of the link pin, should not contact the slide stop pin, either coming or going. If the vertical surface in the frame is too far forward, the barrel will hit it prematurely. If it prevents the barrel from fully seating on the frame, the slide could rub the barrel as it cycles; if there was actual interference between the slide and barrel, it could damage the upper lugs. When the barrel is completely linked-down, is it free of the slide at the top? I think Schuemann likes .015" of static clearance. If you're using a standard-length link, the slide is not rubbing on the barrel as it cycles, and there is evidence that the barrel is stopping on the vertical surface in the frame, then the timing/fit seem to be OK. Are you having problems that lead you to believe something isn't right?