After the pressure ring expands then case tapers back to the shoulder. If you mark the length from start of case body to pressure ring then mark that same length forward toward the shoulders that dia is just little larger on my cases.
Height of pressure ring varies since you get that from start of case body to rim which that thickness varies.
If some tell me that case taper more toward the start of the case body I don't have chambers like they do same with height of pressure rings.
VFW Life member
NRA Life Member