40-70 sharps bn?

Hello to all,

I have what I think is a 40-70 SHARPS Bottle Neck but it has a small primer, .184 dia.

Fred Datig’s Vol 1, makes no mention of a small primer and I haven’t been able to find anything searching the archives here so far.

Case dims are:
Bullet dia .403
Case neck dia .426
Case base dia .503
Rim dia .595
Case AOL 3.42
RN, convex base, no H/S

Any insight would be appreciated


many times the size of the primer is more indicative of which manufacture made the cartridge not what cartridge it is. Example is the 50-70 which has a farrington primer is indicator for USCCo made cartridges not just 50-70. Vic