[Ron Wood]

I really doubt that the gun is 9mm. Model 1906 American Eagle Lugers are occasionally found with the circled B marking on the barrel. There was the notion that these were left over spare barrels from the Brazilian contract, but since the Brazilan guns did not have that mark on their barrels it is more likely that a DWM inspector just chose that die for his purposes. Evidently there is some operation in the assembly and inspection of early Lugers that required an additional barrel inspection. In addition to the circle B you will sometimes see a shield shaped mark with a diagonal line across it, just another DWM inspector mark.