Graf
Thanks for the 1909 photograph. It is of interest that the C/X, C/X acceptance stamps on your 1909 Erfurt rifle are the same, except for the number of lobes on the crown, as those found on the 1908 and 1914 Commercial Army Lugers, and some 1914 dated DWM w/o stoch lug.
It has been claimed that the odd featherless proof found on the two known 1910 Erfurt Lugers is the same as that on an Erfurt 1910 Kar. 98a. I recently obtained photographs of a 1910 Kar. 98a proofs and it has feathers. The proofs on 1911 Erfurts serial number 2 and 3 also have feathers (Paolo). In short, the test proofs found on the two known 1910 Erfurt's are different (featherless) than the first 1911 Erfurts produced and are also different than the one 1910 Kar. 98a Erfurt reported.
Jan