Several of us were discussing pre-war SxS guns on another thread...with barrels carrying with the 3-ringe Krupp logo, and often their eagle symbol. The discussion was about Berettas, but a question arose that applies to any pre-war double: "where did those barrels really come from?"

> During the Pre-WWII era both Beretta and also Krupp had the fabrication capabilities to produce shotgun tubes; however some believe Krupp never actually fabricated ANY shotgun tubes in the rough - but rather sold ingots to other machinists for fabrication
> In addition to fabricating steel, Krupp developed steel recipes/formulas and production processes to yield a given steel product; they licensed other (non-Krupp) mills to make this steel and sell the product as "Krupp Steel"
> During that same era Belgium was also a major production center for tubes. Several firms there, such as Sauer, had license agreements with Krupp to finish raw blanks into rough tubes and sell them as "Krupp barrels". Belgium was producing hundreds of thousands of tubes each year.
> Beretta catalogs from that era prominently mention, you could even say 'tout' Krupp steel, “Special” Krupp, “Special Long-Range” Krupp, and “Prima” Krupp steel. Krupp was mentioned often as the steel used for actions as well. Krupp name/logos are either on the flats or more prominently stamped on barrel tops…sometimes featuring the Krupp Eagle.

So…the question is:
> did Krupp make the steel and also form rough or finished tube sets in Essen, then sell them to Beretta or other gun makers?
> did Beretta purchase Krupp ingots and fabricate the tubes in Gardone?
> did a machine shop in Liege or Jupille (such as Laurent Lochet-Habran) buy Krupp ingots, shape the barrels, then sell them to Beretta for final fit & finish?

Who actually fabricated these Beretta barrels? There is a possibility that stamp marks on the barrel undersides might indicate a maker, but the sole example I have from 1932 doesn't seem to carry such a stamp.

Do you have a pre-war Beretta gun that might have such a mark? Or do you have any information from back in the day that would shed light on pre-war guns carrying Krupp-labeled barrels?