Re: Winchester Brass
Popeye,
Could be due to a couple of factors:
1) how clean is the primer pocket?
2) any powder, polishing media or other crap, on your primer ram, causing a slight misalignment, as you try to seat primers? Any little dents on some of your seated primers?
3) Federal primers seem to fit a little more snug than the CCI or Win., in my experience.
4) Check for Primer crimps.
I load on a Dillon 550 as well. When I screw up a primer, or it feels a litle "off" while seating it, it's usually due to one of the above.