This may be one of those "forest for the trees" things but it just escapes me. If pressures are determined in part by bullet seating depth, and if different brands/types of bullets have different base lengths, why don't we factor in the difference in determining the overall cartridge length? For instance, if I have a round nose lead bullet, 200 grain and a flat nose 200 grain if I seat each by the same amount of bullet in the case, the pressures, and therefore the load data, should be the same.

Is there some standardization in where manufacturers put the crimp ring? It doesn't seem to always conform to the depth requirement in the load data sheets? Nor does it seem to be a consistent distance from the bottom of the bullet.

Help me out please. What am I missing?