Regarding head expansion or pressure ring expansion measurements...would the following method have a decent degree of accuracy?
Fire several rounds of factory ammunition and measure.
From the same box of ammo, pull bullets, dump powder, and remove primers from several rounds.
Replace primers with what you want to use; do the same with powder and bullets.
Fire several rounds, record measurements and compare with initial measurements of factory ammo. Of course, chronograph everything.
This is assuming that the brass in one box is all from the same batch and has identical metallurgy. Is that a reasonable assumption?
