With the "mm" stamp, I'd say it was post 1910 if thru the Suhl proofhouse and possibly during WWI, but of course there are exceptions. I'd say Suhler is that of Suhl; i.e., Weapon's maker of Suhl.
Art:
I'm just not confident on the heart shaped/encircled "K" by a "W" being the mark for the bolting of the tube to the action as noted by Axel Eichendorff, who is/was a Forester in Germany and was born in 1948 I think. Almost all other forges/tube makers had a double stamp noting the tube was forged in their shop. Early on the initials denoting the craftsman who bolted the tubes to the action were closer to the action and as mechanization played much larger role, the initials migrated toward the forend lug and became script. Axle Eichendorff and I have been and are in discussions and of course I would default to him if he had a reason. There are certain tasks performed in making a tube such as forging the tube, drilling a pilot hole, cutting the rifling, and finally profiling the tube. A specific stamp may have denoted each process. Also, sometimes the rifling was cut at the very last. At present, I'm leaning toward the caveman stamp on the flats being associated with profiling/finishing the tubes. But something had to denote cutting the rifling.
The following is Suhler Gewehrfabrik in 1892 and depicts a few tasks:
So if there was an example and an order form, by viewing the marks we might just answer the question of what stamp meant what. Then again we may never know???
Kind Regards,
Raimey
rse
