Raimey, thank you once again for your exhaustive research. How did you find the Google book reference? I had search time and again on "Monopol" and Francotte but never found that link... I will take the casting into consideration. Regarding the rough circle stamp, there does appear to be a "K" to the naked eye, which dissolves into uneven textures under a loupe. However, I'm not certain I am seeing the "K." I'll take photos of both the mark and the rifle chamber tomorrow for your consideration.
Chris:
Ah, after performing 1000s of Google searches one learns to throw out the obvious and try innovative combinations. But that will lead to permutations, which will get you closer to the desired result. Many times searching in another language helps, but keep in mind the books have to be scanned.
Here's an image of a jagged encircled "K" from a Robert Schlegelmilch bolt gun that was in Steven Dodd Hughes' shop:
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Kind Regards,
Raimey
rse
