emmm…sorry，I made a mistake…“北洋三七”was produced in 民国三年七月=July 1914≠March，ehhh，embarrassing😓
OK，I have corrected it
No worries…none of us knew the difference!
… but now we do! ;-)
The markingl “X” is very similar to one I have on a brass body 7,9x57 charger, is there a meaning to this symbol ?
The "X"on my 7.9 case is the Chinese character"七"in fact. “七"is the meaning of"7”，usually used to mark when it was produced. emmm…might the "X"on your charger is similar to mine?…I’m not sure
X IN 7.92*57 MEANS SEVEN。七 （Chinese digital）
but this X .i dont know.
very interesting. thank you for sharing!