BB,
In my quick survey for this article I have 6 20DWM; 2 1920 Police; 2 1921 Police; and 4 1921 Military. All firing pins are unmarked.
If you would, please let me know the serial# of your Luger, and the presence or absence of a serial number--on the breechblock, front toggle, left reciever, receiver locking lug, holdopen, grips, rear toggle. Also WaA if present.
If you prefer, email me
dwightg@pacifier.com
Thanks much.
--Dwight