Sizing die setting shoulder back but not sizing case mouth

Tracer847

Default rank <200 posts
Hunter
2   0
Joined
Feb 29, 2020
Messages
115
Reaction score
140
Location
Dallas
The mandrel is too big or you turned the necks down to where it’s not sizing anymore. What else could it be? Two thousandths total or the cutter cut .002”….if so then you are .004” Less on OD.
 
217   0
Joined
Jan 6, 2016
Messages
3,741
Reaction score
4,943
Location
Bogart
Couple thou off the neck, the effect is doubled because you have two walls in play when measuring diameter of the OD. .002x2=.004. .308 (normal ID) + .004 (removed material from OD = .312. Your walls are too thin and its affecting the ID.

Even removing .001 from the neck OD would result in an ID of .310 and your slugs would be slightly loose, really needing to be crimped to retain seating depth under recoil.

Possibly use a collet style neck sizer to squeeze them down a bit more than "normal" as an option or trash the brass.
 
Top Bottom