Lee 30 M1 Carbine and 32-20 Collet Style Factory Crimp Die crimps the bullet in place more firmly than any other tool. Tests demonstrate that even bullets which have no crimp groove will shoot more accurately. A firm crimp improves accuracy because pressure must build to a higher level before the bullet begins to move. This higher start pressure insures a more uniform pressure curve and less velocity variation.

The 32/20 has very thin case walls, this factory crimp die may leave noticeable gathering marks on the neck of the case. There is nothing that can be done to remove these marks.