I set up my sizing dies with Wilson type cartridge headspace gages. To verify that this cartridge gage was cut correctly, I inserted chamber headspace gages into the thing.
The lower ridge corresponded to the Go gage and the upper corresponded to the No Go gage.
The Wilson cartridge headspace gage is cut wide between the shoulders and the base, so you can insert a fired case and measure the actual headspace of your chamber. The Wilson gage measures "length", not "fatness".
Anyway, I set up my dies so the cases are sized to gage minimum. I have had dies that would not size the case to a minimum headspace. The die body was too long, so I ground material off the base. It worked.
