I was making a dummy cartridge to test seating depth in a 357 TC and noticed that the cartridge was dragging noticeably in the Redding seating die. The dummy bullet was as-cast so it was 0.360" - 0.361". I wondered if the oversize bullet was getting squeezed by the seating die, so I did some measuring.
I pulled the bullet from the dummy cartridge and measured -- it had indeed been squashed down to 0.3591". That could be due to the soft air-cooled bullet getting squashed by neck tension, but that wouldn't explain why the cartridge was dragging in the seating die ?
So I cleaned up the seating die and measured its ID -- 0.3795". When loaded with a 0.359" bullet, my cartridges generally measure 0.378" - 0.379" OD, so the seating die was a tight fit!
I want to be able to load 0.360" bullets without them getting squashed in the seating die, so I honed the seating die out to 0.3803"+.
BTW, these were not "profile crimp" or taper crimp dies, just ordinary Redding dies that I purchased in the mid-80's. They started out as 357 Maxi dies but I later shortened the dies to work with 357 mag cases.