Carhub48
Actually, the relationship is a happenstance. The 8,7 is the bore (not groove or bullet) diameter, as measured by the proof house, using plug gauges (in o.1mm steps). The 72 is the length of the case, without regard to shape or diameter, and was also applied by the proof house. The 9.3x72R is the nominal cartridge for which the rifle was chambered. From the implementation of the 1891 proof law in Mar.1893, bore diameter was marked by the proof house in gauge measurement (similar to shotguns) and the case length was not marked. Your gun would have likely been marked 118,35. Because this was confusing, the old system was improved and after about 1911 until the proof law of 1939, the system on your gun was used. In accordance with the '39 law, it was required that the gun maker clearly mark new guns with the commonly used name of the cartridges they were chambered for. This seems to have cleared up lingering confusion.
Mike
P.S. Carhub48,
Most of the random letters and shaped marks are individual's touchmarks. They identify the work done by each, for payment as well as establishment of responsibility. It is pretty much a lost cause, at this late date, to identify these workers, with any certainty, since there was no centralized record of these marks kept. Established manufactures of some components, such as barrels sometimes used recognizable marks, however.
Mike
Last edited by Der Ami; 04/25/22 04:34 PM.
