DETAILED DISASSEMBLY OF THE RECEIVER GROUP.- Disassembly of the receiver group into its individual parts, as shown in figure 3-5, is done as follows:
1. The hammer should be in its cocked position. Move the safety lockup and down and, at the same time, pull it outward from the receiver. (Do not use any tool to pry the stop out.) With the safety lock removed, squeeze the trigger, and allow the hammer to ease forward.
2. Remove the mainspring housing pin. This step requires a good deal of force, so the receiver must be placed on a sturdy supporting surface. The end of the safety lockpin cart be used to push the mainspring housing pin out.
3. Remove the mainspring housing. Take out the grip safety and the sear spring.
4. Using a driftpin, punch out the hammer pin; then lift the hammer from the receiver.
5. Drift out the sear pin from right to left, and let the sear and disconnector drop out into your hand.
6. Press the magazine catch in until it is flush with the left side of the receiver. Then, using a suitable screwdriver, turn the magazine catch lock one-quarter turn counterclockwise. Lift the magazine catch from the right side of the receiver.
7. Remove the trigger from the rear of the receiver.
8. Remove the four stock screws and the left and right stocks.
Assembly of the weapon is also covered in two phases. First, the receiver group is assembled. At the end of this phase the weapon is in a field stripped condition. Then the field stripped weapon is assembled.
Both phases of assembly are done by performing the disassembly procedures in reverse order. Here are four hints that should be helpful in assembling the pistol:
1. All the pins go in from left to right.
2. Place the sear and disconnector in as one unit, fitted together, as shown in figure 3-6.
3. When you place the sear spring in position, have the mainspring housing ready to slide up about three quarters of the way into the receiver to hold the spring in place.
4. Make sure the hammer strut is actually fitting well down into the mainspring cap before sliding the mainspring housing into place. (Sometimes the hammer strut will catch on top of the cap instead of properly seating in the recess of the cap.)
Three safety features and one positive safety are on the .45-cal. pistol. The three safety features are the half-cock notch, the grip safety, and the disconnector. The positive safety is the safety lock (sometimes called the thumb safe).
The safety lock positively locks the slide in the forward position. In addition, a stud on the safety lock
Figure 3-6.-Replacing the sear and disconnector.
(fig. 3-7, view A) blocks the shoulders of the sear to prevent any movement of the sear out of the full-cock notch of the hammer.
The half-cock notch is the notch just above the full-cock notch. It has a lip that prevents movement of the sear from that notch when pressure is applied to the trigger. (See fig. 3-7, view B.)
The grip safety (fig. 3-7, view C) indirectly stops any movement of the sear by blocking the trigger movement. If the trigger cannot be actuated, the sear cannot move and the hammer will not fall.
The disconnector and sear (fig. 3-7, view D) prevents firing unless the slide is fully forward and locked. Anytime the slide is not fully forward, the nose of the disconnector is forced downward. In this condition the disconnector spade does not contact the sear when the trigger is pulled. When the trigger is pulled, the disconnector will be pushed to the rear; but the sear remains in position, holding the hammer to the rear.
When the slide is forward, the disconnector rides up into a recess on the underside of the slide. The spade of the disconnector (dark area) bears against lugs on the sear. When the trigger is pulled, the trigger yoke pushes back against the disconnector spade, which transmits the motion to the sear, rotating the sear nose out on the full-cock notch of the hammer, and the weapon fires.