From Tom Rowe: "Alte Scheibenwaffen Vol.2": Hermann Schneider,gunmaker, Markt 4, Zella-Mehlis. Mentioned from 1912 to 1936, when it was under the direction of Rudolf Schneider. One of the at least 12 Schneiders active in the Zella-Mehlis guntrade. Apparently in this case Schneider made to order this rifle directly for an individual customer, as the Z-M gunmakers usually made guns for the trade and left the "maker" signature to the retailer. Probably it is chambered for either the 8x57I (pre-WW1) or the 8x60I (post-WW1), bored and rifled for the then "civilian" .318" bullets. Have a look at the proofmarks under the barrel shank. Beneath the crown/BUGN proofmarks you will find the designation for the Bore (Not rifling or bullet) diameter, a gauge number like "156,14" or "172,28" if pre-1911, or "7,8" mm if post. Next there ought to be the original case length, either "57" or "60". A proof date like "10.23" for Oct.1923 follows, then, if Z-M proofed, a ledger number. For safety, slug the barrel and check the chamber before using modern ammo! A nice German prewar Mauser and a very tastefull restocking job!