Yes, passed thru the Suhl proofhouse in June 1931. Tube making effort by Heinrich Krieghoff with possibly the tube knitter being Wilhelm Kelber. I had attached a small probability of a script stamp of "LK" being attached to Ludwig Kreighoff, who expired in 1924 +/-. But this reveals that even Kreighoff sourced the best of the best, one of the Kelber boys. High quailty tube steel fastened to the receiver by one of the best, Wilhelm Kelber. Heinrich Krieghoff traveled to Liege, one of several gunmaking centers he visited, to learn the art of mechanized production of tubes. Nitro proofed more than likely a tight chambered 8X72(maybe Sauer - not 9.3X72R as Mike Ford called my hand and put me on the straight and narrow. Not sure on the name. I think you've stumbled on the best sight although GGCA( www.germanguns.com ) might provide some info, but it will be more than likely from Shotgun Charlie, or Axel E. who should be along shortly.

Kind Regards,

Raimey
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