I have a Krieghoff Bockbüchsflinte in caliber 7X75R SE vom Hofe and 12 gauge. The addition of a full length insert barrel in caliber 6X52R Bretschneider turned it into a Bergstutzen. The 7X75R cases are formed from 9.3X74R brass and the cartridge has proven to be highly effective on white tail deer.