Adding to the discussion with sharps4590 regarding German double rifles chambered for the .43 Mauser cartridge, here is another example:

This gun is proofed "Nitro" using a 18 gr (278 grain) K.m.G. (Kupfer Mantel Geschoss - Copper Jacketed Bullet). The barrel length is 26 1/16” (66.2 cm).





















Regards,

Buchseman