05-01-2020, 06:35 AM
Cs,
Interesting, that Lee sizer is working your brass like Conan the Barbarian.
The neck of your chamber has been generously reamed (.300-.301). Fired cases are then squeezed to .279 which is .021" of squeeze/stretch. Doing this every time is going to work-harden and split the neck. I would ditch the Lee sizer and get a better one: Forster, Redding, Hornady.
Interesting, that Lee sizer is working your brass like Conan the Barbarian.
The neck of your chamber has been generously reamed (.300-.301). Fired cases are then squeezed to .279 which is .021" of squeeze/stretch. Doing this every time is going to work-harden and split the neck. I would ditch the Lee sizer and get a better one: Forster, Redding, Hornady.