AUTOMATIC PISTOL, CALIBER .30 MODEL OF 1918 - During World War I Mr. J.D. Pedersen designed a device which, inserted into the receiver of a modified Model 1903 rifle, gave the rifle the capability of firing 40 pistol sized .30 caliber bullets in semi-automatic mode. Secrecy surrounding the development of this 'Pedersen Device' resulted in it being called an automatic pistol.
M1903 Mk.I without Pedersen Device SPAR6292
M1903 Mk.I with Pedersen Device SPAR1324