IMHO a BSW - made KKW = KleinKaliber Wehrsportgewehr, Mauser designed, forerunner of the Mauser Mod.45. Restocked post-WW2 (white line spacer!). Retains "military" rear sight, scope mount base added. The KKW was a single shot. The postwar, French occupation Model45 had a magazine added and the rear sight relocated to the receiver bridge. See Jon Speed's book "Mauser Smallbores - Sporting, Target & Training Rifles". BSW = Berlin-Suhler Waffenwerke was the name of the expropriated Simson, Suhl factory from 1936 to 1945.