The other mark is a poorly stamped 'F' indicating Full Choke.
Those are the only markings on the bottom of the tube.
The 'F' is just barely visible when the gun is assembled,,the Crown/D is not,,all due to the magazine tube.
Normal roll marked bbl address on the left side of the bbl and large '12GA' marking.
Nothing in there to indicate steel type.
It's not a composition type bbl (twist,damascus,ect). Solid steel (fluid?)type instead.
No additional choke marking in that side marking.
I suspected the mark indicated a foreign source for the pump gun tube, but figured I'd ask here to make sure.
The Model was made in the 1920's and was surprised at the 'foreign' looking mark at first.
A Meriden Pump Shotgun I have is clearly marked 'Fluid Steel Krupp Essen' on the top of the bbl.
AFAIK those Meridens were made in 1917 or '18.
I wouldn't have figured Krupp would have been obliging to us at that particular time for bbl steel. I'm sure there's an answer and probably just to do with aquisition and later production timing.
Maybe all not so surprising. If we (USA) sourced SxS bbls into the 20th century,, why not repeater bbls as well..
Thank you both for the information & interest in the marking..
