Reheinische Metallwaren und Maschinenfabrik / Rheinmetall-Borsig was founded by Heinrich Ehrhardt in 1899 and that was in Dsseldorf.
A similar concern was founded in Smmerda in 1901, which was a specialist for tubes and probably the source for the Rheimetall trademarked tubes.
Is there a worn mark near the script L on the lower rib? I have seen a similar script L on many of Sauer's offerings. More than likely a Langenhan mechanic.
It passed thru the Zella - Mehlis proof facility in September of 1921 being Nr. 535 for the month of September.
Cheers,
Raimey
rse
