Colt Model 1911A1 - Blued Colt M1911A1 .45 cal. S/N 722645, the slide is unnumbered, CSR inspectors mark on left side of the frame and on the top of the frame near the disconnector.  Pistol has a 1938 replacement slide.

Pistol has a 1938 replacement slide with M 1911 A1 U.S. ARMY.on the right side and P proof on the top in front of the rear sight. 

Left side of 722645

There is a P proof on the top of the slide, in front of the rear sight and alto a P on the left side of the frame near the magazine release button.

The initials of Major Charles S. Reed (C.S.R.), Officer in Charge of Outside Inspection, were stamped on all M1911A1 pistols manufactured in 1940, signifying government acceptance of the pistol.  His initials were stamped on the left side of the receiver below the slide stop in accordance with Ordnance drawings.  The initials C.S.R.  were also stamped on the top of the receiver near the disconnector hole to indicate provisional inspection, replacing the previous letter "R" within an oval.

Feed ramp is in the white, but has turned slightly brown with age.

The barrel in this gun is marked COLT .45 AUTO on the left side, with the G in front of the barrel lug on the underside of the chamber.  There is a P laying on its back on the left lug.

There is a P proof on the top of the slide

1938 Replacement Slide is unnumbered under the firing pin stop and has G stamped inside next to the firing pin.

Front grip strap.

Underside of pistol showing front grip strap, trigger guard and underside of frame and slide.