Trying to help out a friend who contacted me today and I'm kinda stumped. Here's what I do know, he fired virgin Nosler brass with no issues, he then full length sized with a Redding die and he did say that it was tough coming out on the downstroke. These were loaded a grain under Nosler book max with Magpro and the same splits happened with 140gr Partitions and 130gr Ballistic Tips. Any help would be greatly appreciated.