Hello Aaron,
I do have a '41 byf "Black Widow" (from WWII) that is full of British proof marks including :
1. Not English Make, on right side frame rail.
2. Crown/GP encircled with NP, on barrel.
3. 4-5 Crown/V encircled over many parts including barrel, right ear, on both top surfaces of toggle links, and top of breechlock.
On the old Forum, you can do a search on "Black Widow" and read when I was asking members for help to ID these British proof marks.
From the previous owner (not the dealer) I learned my BW came from England to the States in the 1950's...
I am not one to rebute whether such British markings detract from my luger's value or not. I have come to "love" them and would not want a BW without them...they thrust me into quite a learning curve hunting down their origins.
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