Refer to figures 3-3,3-4, and 3-5 as we explain the functions of the pistol. We will assume that a loaded magazine is in the weapon, a round is in the chamber, the grip safety is depressed, the trigger has been squeezed, and the round fired. The cycle of operation now begins.

As the gases from the burned powder expand, the bullet is forced down the barrel while the same force is directed rearward against the slide. The slide and barrel are locked together at this point, and both are forced aft. The barrel link is pinned to the receiver by the slide stop shaft and to the barrel by the barrel link pin. As the barrel moves rearward, it pivots on the slide stop shaft and is moved downward as well as to the rear. As the barrel locking ribs are disengaged from the recesses in the slide, unlocking is completed.

As the slide moves aft in recoil, the extractor pulls the empty case along with it. Extraction is completed when the cartridge clears the chamber.

Ejection occurs when the cartridge strikes the stationary ejector, pivots on the extractor, and flips from the weapon through the ejection port.

Cocking begins as soon as the slide started its recoil movement. The hammer is moved rearward and the hammer strut is pushed down against the mainspring,

Figure 3-7.-Safeties on the .45-cal. pistol.

compressing it. When the slide strikes the recoil spring guide collar, its rearward movement is stopped. The recoil spring then causes the slide to begin its forward movement. The hammer follows the slide for a short distance. Then the sear, which bears against the hammer through the action of the sear spring, enters the full-cock notch of the hammer and holds it in a cocked position. Feeding starts as soon as the slide, moving to the rear, clears the top of the magazine. The magazine follower, under pressure from the magazine spring, forces the top round against the lips of the magazine. This places the top cartridge in position to be picked up by the face of the slide during its forward movement.

Cambering occurs when the forward moving slide pushes a new round into the chamber. As the bullet is pushed up the ramp into the chamber, the base of the cartridge slides up the face of the slide. As this happens the groove on the base of the cartridge is engaged by the hooked extractor.

After cambering, the slide continues forward a small distance, pushing the barrel ahead of it. As the barrel moves, it pivots up and forward on the barrel link. The locking ribs on the barrel enter the locking recesses in the slide, thereby locking the two together.

Firing will start the cycle all over again. When the grip safety is depressed and the trigger is squeezed, the trigger yoke presses against the disconnector, which pushes aft on the sear. The sear rotates on its pin, disengaging from the notch on the hammer. The mainspring pushes up on the hammers strut, roataing the

hammer forward. The hammer strikes the firing pin which, in turn, strikes the cartridge primer.

For more information on the M1911A1 .45-cal. pistol, refer to U.S. Army TM 9-1005-211-12.