The shells do reload differently than old AA's. If your load is set up for regular AA's, stick to those. The spot just inside the hull, coming from the primer, is different. More \/ shaped than W shaped. This makes the powder sit differently in the shell, higher. Thus causing the shot column to sit higher in the hull, thus throwing off your crimp. I had alot of trouble with these when they first came out. Now when I see them I just let them lay.