Re: 270 Wby brass won't go into sizing die!!
According to the drawing on Quickload, the diameter in front of the belt on 270 Weath Magnum should be .512", so that does not appear to be your problem.
Have you tried to remove the depriming rod completely from the equation? Is the rod contacting the web inside the cartridge?
If some is good and more is better, then too much is just right.
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