Couple of basic questions from a new guy

I’m trying to ID some of the paper patched rounds that I have and while doing some measuring I realized I needed to ask a question or two.

Is bullet dia measured at the the paper or the lead?

With a “stepped” base, is Case Length measured from the step or out at the rim?

It seems that the difference in measurement would be important?



Patched bullets are measured on the patch. A patch is usually two complete turns (4 thicknesses). Patch material can be found in varying thicknesses depending on the type of rifleing and the preference of the shooter. Therefore, the diameter will vary likewise.

Case length usually means the longest measurement of a cartridge case.