I think I have a donut issue with my Nosler 300 rum brass. Basically, I tried to seat a bullet and it would go in smooth then get real tight at bottom. I had two that the bullet just hit a brick wall and would not seat any further. The brass is 2 or 3x fired. This is my process:
Uniform flash holes and primer pockets if new
Clean necks
Neck size and deprime with Wilson dies
Clean primer pockets
Bump shoulder and body size with Redding die
Trim after each firing
Debur and chamfer
Seat primers
Load
Seat bullets with Wilson dies
So what causes donuts? How can they be avoided? Were they due to loads being too hot or soft brass? Can you get rid of them with expander mandrel?
Thanks,
DoubleG