The Gun Digest Book of Tactical Weapons Assembly/Disassembly. J B Wood
of the slide stop.
4. Push the end of the slide stop shaft, on the right side of the gun, and remove the slide stop from the left side.
5. The slide assembly can now be run forward off the frame.
6. Remove the recoil spring and its guide from the slide, together or separately.
7. Turn the barrel bushing back toward the left side of the slide, until its lug aligns with the opening, and remove the bushing from the front of the slide.
8. Tip the barrel link over forward to clear the recoil spring tunnel.
9. Remove the barrel from the front of the slide. Gun is now field-stripped.
Colt Mk IV/Series 70 field-stripped
Detail Strip:
10. With a tool of appropriate size, depress the firing pin and slide the retainer downward to free the firing pin. CAUTION: The firing pin spring is under some compression, and can eject the firing pin with force when the retainer is removed.
11. After the retainer plate is removed, the firing pin and its return spring can be taken out.
12. Removal of the firing pin retainer plate also frees the extractor. With a small screwdriver pry it gently out, straight to the rear of the slide.
13. When the extractor is pried out past its round headpiece, it can be easily grasped with the fingers and removed from the slide. The rear sight can be drifted out of its dovetail slot from left to right.
14. The initial takedown key for the frame is the mainspring housing retaining pin, located at the lower rear edge of the grip frame.
15. With the hammer at rest, use a drift of the proper size to drive out the mainspring housing retainer pin.
16. The mainspring housing can now be slid down off the frame. If it is tight, cocking the hammer will put pressure on it through the mainspring and help to ease it out.
17. Viewing the mainspring housing from the rear, there is a small pin (arrow) at upper right which can be drifted out toward the inside to free the mainspring and its plunger. CAUTION: The mainspring is under quite a bit of tension and can cause injury when released. Use a heavy shop cloth to catch it when driving out the pin.
18. With the hammer cocked, move the safety almost to the on-safe position while exerting slight outward pressure toward the left. When its internal projection aligns with its cut in the frame, it can easily be taken out.
19. Removal of the safety frees the grip safety and this is now removed to the rear.
20. The combination leaf spring which powers the sear, trigger, disconnector, and grip safety can now be lifted out at the rear of the grip frame.
21. Pushed from the front with a drift of proper size, the spring and plungers which supply tension to the slide stop and manual safety can now be removed from the rear of its tunnel above the left grip. The spring tunnel is riveted in place inside the magazine well and it is difficult to remove and replace without special tools. Unless removal is absolutely necessary, it should be left in place.
22. Started from the right with a drift of the proper size, the hammer pin is removed from the left side of the grip frame.
23. The hammer can now be lifted out of the frame.
24. Removal of the small pin at lower rear of the hammer will free the hammer strut. Note the direction of its curve, and replace it in the same position.
25. Starting from the right side with a drift, remove the sear/disconnector pin from the left side.
26. The sear and disconnector can now be removed from the rear of the frame. Note their relationship for proper reassembly.
27. With a small screwdriver, turn the slotted head of the magazine release retainer to the left, while keeping the magazine release depressed to the level shown.
28. With the retainer locked into its slot in the magazine release, the release can be taken out toward the right side of the gun. After removal, turning the retainer back to the right will free the retainer and its spring from the release body. These are small parts, so take care that they aren’t lost.