Recoil Rob,
While tight, 7.6 bore( not groove or bullet) diameter is often found in 8.15x46R rifles. I believe the number is a "6". I agree that the light strike of the bore diameter is highly unusual. The 1912 date is close to the time the proof marks changed. We sometimes see strange things done during the transition period. Maybe they were trying to adapt an old number stamp set- maybe something else. You can't really determine the cartridge from proof marks until the 1939 law that required showing the common name was implemented. You can make very good guesses in most cases however. The DWM case numbers in most cases ID the name of the cartridge but are not the same as proof marks.
Mike
Last edited by Der Ami; 09/30/19 06:59 PM.
