5. Disassembly and Assembly
(a.) The individual soldier is authorized to disassemble his rifle to the extent called field stripping.
(b.) The rifle should be disassembled and assembled only when maintenance is required or for instructional purposes. Repeated disassembly and assembly causes excessive wear of parts and soon makes them unserviceable and reduces the accuracy of the weapon.
(c.) The rifle has been designed so that it may be taken apart and put together easily. No force is needed if it is disassembled and assembled correctly. The parts of one rifle, except the bolt, may be interchanged with those of another when necessary; for safety reasons, bolts should never be interchanged except by maintenance support personnel.
(d.) As the rifle is disassembled, the parts should be laid out on a clean surface, in the order of removal, from left to right. This makes assembly easier because the parts are assembled in the reverse order of disassembly. The names of the rifle parts (nomenclature) should be taught along with disassembly and assembly to make future instruction on the rifle easier to understand.
6. Clearing the Rifle
The first step in handling any weapon is to clear it. If the rifle is loaded, unload it as described in paragraph 13. The M1 rifle is clear when there is no ammunition in the chamber or receiver, the bolt is locked to the rear, and the safety is engaged. To clear the rifle, pull the operating rod handle all the way to the rear, inspect the chamber and receiver to insure that no rounds are present and push the safety to its locked position (inside the trigger guard).
7. Disassembly Into the Three Main Groups
(a.) The three main groups are the trigger housing group, the barrel and receiver group, and the stock group.
(b.) To disassemble the rifle into the three main groups, first insure that the weapon is clear and then allow the bolt to go forward by depressing the follower with the right thumb and allowing the bolt to ride forward over the follower assembly.
(c.) Place the rifle butt against the left thigh, sights to the left. With the thumb and forefinger of the right hand, pull downward and outward on the rear of the trigger guard. Swing the trigger guard out as far as it will go and lift out the trigger housing group (fig. 3).
(d.) To separate the barrel and receiver from the stock lay the weapon on a flat surface with the sights up, muzzle to the left. With the left hand, grasp the rear of the receiver and raise the rifle. With the right hand, give a downward blow, grasping the small of the stock. This will separate the stock group from the barrel and receiver group.
8. Disassembly of the Barrel and Receiver Group
(a.) Place the barrel and receiver group, with the bolt closed, on a flat surface with the sights down (insuring that the rear sight aperture is at its lowest position), muzzle pointing to the left. Holding the rear of the receiver with the right hand, grasp the follower rod with the thumb and forefinger of the left hand and disengage it from the follower arm by moving it toward the muzzle (fig. 4). Remove the follower rod and operating rod spring by withdrawing them to the right. Do not separate these parts.
(b.) Using the tip of a dummy cartridge, remove the follower arm pin by pushing it from the far side of the receiver toward the body (fig. 5).
(c.) With the left hand, grasp the bullet guide, follower arm, and the operating rod catch assembly, and lift them out of the receiver together (fig. 6). Separate and arrange these parts from left to right in the following order: follower arm, operating rod catch assembly, and bullet guide.
(d.) Reach down into the receiver and lift out the follower assembly.
(e.) Turn the barrel and receiver group over so that the sights are up, muzzle pointing away from you. With the left hand, raise the rear of the receiver. With the right hand, pull the operating rod to the rear until the rear of the handle is directly under the forward edge of the windage knob. With an upward and outward movement, disengage the guide lug of the operating rod through its dismount notch on the receiver. Remove the operating rod (fig. 7).
Caution: The operating rod is bent intentionally so that it will not bind against the enlarged portion of the barrel. Do not attempt to straighten it.
(f.) With the right hand, grasp the bolt by the operating lug and slide it fully to the rear; then slide it forward, lifting upward and outward to the right front with a slight rotating motion to remove it.
(g.) Using the screwdriver blade of the M10 cleaning rod handle unscrew and remove the gas cylinder lock screw located under the end of the barrel muzzle (fig. 8).
(h.) Unscrew and remove the gas cylinder lock. Loosen the gas cylinder by tapping lightly toward the muzzle on the bayonet stud with a piece of wood or similar soft object. Remove the gas cylinder, taking care not to burr or damage the splines. Do not remove or attempt to adjust the front sight.
(i.) Remove the front handguard by sliding it forward over the muzzle. Do not attempt to remove the rear handguard.
9. Assembly of the Barrel and Receiver Group
(a.) Replace the front handguard by sliding it over the muzzle and insure that it is seated in the front band.
(b.) Place the gas cylinder over the barrel, making sure the splines are aligned with their grooves. Push the gas cylinder down as far as it will go. If tapping is necessary, use a piece of wood on the bayonet stud. Engage the threads of the gas cylinder lock with those on the barrel and screw the lock on by hand until it is finger tight (do not use a tool). If the lock is not aligned with the gas cylinder, do not force it, but unscrew it until it is aligned. Replace and tighten the gas cylinder lock screw with the handle assembly of the M10 cleaning rod.
(c.) To replace the bolt, hold it by the operating lug and place the rear end of the bolt onto the bridge of the receiver. Rotate the bolt counter-clockwise as far as necessary to permit the tang of the firing pin to clear the top of the bridge of the receiver. Guide the left locking lug of the bolt into its groove on the left side of the receiver. Lower the right locking lug on its bearing surface and slide the bolt halfway to the rear.
(d.) To replace the operating rod, hold the handle with the right hand and place the piston end into the gas cylinder. Align the operating rod so that the recess in the hump fits over the operating lug of the bolt. While applying pressure downward and inward on the handle, pull the operating rod to the rear until the guide lug is engaged in its groove. Move the operating rod forward until the bolt is closed.
(e.) Turn the barrel and receiver group over so that the sights are down and the muzzle is to the left. Replace the follower assembly so that its guide ribs fit into their grooves in the receiver. Make sure that the slide of the follower is down and that the square hole is to the rear. The slide will rest against the bolt.
(f.) Replace the bullet guide so that its shoulders fit into their slots in the receiver and the hole in the toe of the bullet guide is aligned with the holes in the receiver.
(g.) With the right hand, lift up the lower part of the bullet guide slightly. With the left hand, insert the rear arm of the operating rod catch assembly through the clearance cut in the side of the bullet guide. Make sure that the rear arm is underneath the front stud of the clip latch which projects into the receiver. Lower the bullet guide into place. Test for correct assembly by pressing down on the front arms of the operating rod catch assembly. It should move and you should be able to feel the tension of the clip latch spring.
(h.) Replace the follower arm by passing its rear studs through the bullet guide and inserting them into the guide grooves on the follower. Allow the wings of the follower arm to rest astride the toe of the bullet guide. Align the holes in the operating rod catch assembly, follower arm, and bullet guide with those in the receiver and replace the follower arm pin from the near side.
(i.) Insert the loose end of the operating rod spring into the operating rod. Grasp the follower rod with the left hand, making sure that its hump is toward the barrel. Pull toward the muzzle, compressing the operating rod spring, and engage the claws of the follower rod with the front studs of the follower arm. You may have to raise the follower assembly to do this.
10. Assembly of the Three Main Groups
(a.) Place the barrel and receiver group on a flat surface, sights down. Pick up the stock group and engage the U-shaped flange of the stock ferrule in the lower band, then lower the stock group onto the barrel and receiver group.
(b.) Unlatch and open the trigger guard. Keeping the base of the trigger housing group level, place it straight down into the receiver, making sure that the locking lugs on the trigger guard enter their recesses in the receiver. Place the butt of the rifle on the left thigh with the sights to the left. Close the trigger guard and latch it by striking it with the heel of the right hand. The trigger guard is latched while the rifle is in this position so that the rear sight will not be damaged.
11. Test for Correct Assembly
Each time the rifle is disassembled and assembled it should be
tested to make sure that it is put together properly. To do this,
pull the operating rod to its rearmost position. The bolt should
stay open. Close the bolt and snap the safety to its locked
position. Squeeze the trigger. The hammer should not fall. Push
the safety to its unlocked position and squeeze the trigger. The
hammer should fall. This test is made to check the operation of