A few guestions from a new Luger owner...

[Luke]

You asked about the small proof mark in the last picture. Yes, that proof was applied at the time the holdopen was retrofit to the frame. The pin right above the proof indicates that a holdopen was added after the gun was manufactured.

According to Jan Still's "Imperial Lugers" the holdopen was integrated into DWM Luger frames during the latter part of the 1912 production run and in all subsequent units. So, 1913s should not have a retrofit holdopen.

Often Finnish Lugers are made up of Luger parts with no consideration for matching numbers. Does the frame serial number match your other numbers? It is probable that the frame is from the 1908 to late 1913 period, as it does not have a stock lug. Stock lugs were added by DWM in late 1913.

Luke