One way to deal with excess headspace on a rimmed cartridge with a bottleneck is to fire some cases in that gun, then adjust your dies by backing them off in the press to just size the case without pushing the shoulder back. It may take a few cases to get it just right, but then you can use some shim stock to measure this gap between the die and the shellholder with the ram of the press all the way up, so you can replicate it later.

Last edited by Chuck H; 08/21/10 12:12 PM.