Both of the BSW guns that I've had were chambered and marked for the "export" (70mm/2 3/4") shells. And both showed signs of having been exported or at least marked for export: one had the markings of a retailer/gunshop in Salonika, the other had a "Germany" marking. Both were choked tighter than a gnat's you-know-what in both barrels. Very Germanic. And they both had the famous "goose-stepping duck" on the bottom of the receivers.