1. WEAPONS FAMILIARIZATION BRIEF
SFC LARKIN

2. M9 Pistol
The M9 pistol is a 9-mm, semiautomatic, magazine-fed, recoil-operated, double-action weapon. It is chambered for the 9-mm cartridge.

3. COMPONENTS
The major components of the M9 pistol include--
a. Slide and Barrel Assembly: Houses the firing pin, striker, and extractor. Cocks the hammer during recoil cycle.
b. Recoil Spring and Recoil Spring Guide: Absorbs recoil and returns the slide assembly to its forward position.
c. Barrel and Locking Block Assembly M9/Barrel Assembly M11: Houses cartridge for firing, directs projectile, and locks barrel in position during firing.
d. Receiver: Supports all major components. Houses action of the pistol through four major components. Controls functioning of the pistol.
e. Magazine: Holds cartridges in place for stripping and chambering.

5. GENERAL DISASSEMBLY OF M9 PISTOL
To disassemble the pistol, perform the following procedures:
a. Clear and unload the pistol.
b. Depress the slide stop and let the slide go forward.
c. Hold the pistol in your right hand with the muzzle slightly raised.
d. Press the disassembly lever button with your forefinger.
e. With your thumb, rotate the disassembly lever downward until it stops.
f. Pull the slide and barrel assembly forward and remove it from the receiver.
g. Carefully and lightly compress the recoil spring and spring guide. At the same
time, lift up and remove them. Allow the recoil spring to stretch slowly.
h. Separate the recoil spring from the spring guide.
i. While pushing the barrel forward slightly, push in on the locking block plunger.
j. Lift and remove the locking block and barrel assembly from the slide.

6. M4 Carbine Description:
Lightweight, gas-operated, air-cooled, magazine-fed shoulder fired weapon that can be fired in either semi-automatic or three round burst mode.

7. Characteristics Elevation Knob Windage Knob Handguards Carrying Handle
Rear Sight Assembly
Front Sight Assembly
Charging Handle
Ejection Port Cover
Bayonet Lug
Forward Assist Assembly
Sling
Buttstock Assembly
Magazine Catch Assembly
Trigger

8. Characteristics Front Sight Post Bolt Catch Compensator Selector Lever
Slip Ring

9. M4 Disassembly Remove Sling
Remove Handguards if possible depending on variant.
Remove Upper and Lower Receiver
Remove Bolt Carrier group and Bolt
Remove Charging Handle
Disassemble Bolt Carrier group
Remove Firing Pin Retaining Pin
Remove Firing Pin
Bolt Cam Pin
Remove Bolt
Remove Buffer and Buffer Spring

10. M4 Assembly Replace Buffer and Buffer Spring
Assemble Bolt Carrier Group
Replace Bolt
Replace Bolt Cam Pin
Replace Firing Pin
Replace Firing Pin Retaining Pin
Replace Charging Handle
Replace Bolt Carrier Group
Attach Upper Receiver to Lower Receiver
Replace Handguards
Attach Sling

11. M249 SAW
The M249 machine gun is a gas-operated, air-cooled, belt- or magazine-fed, automatic weapon that fires from the open-bolt position (Figure 1-1). Its maximum rate of fire is 850 rounds per minute. Ammunition feeds into the weapon from a 200-round ammunition box containing a disintegrating, metallic, split-link belt. Only in emergencies do M249 gunners use a 20- or 30-round M16 rifle magazine, in part because this increases the chance of stoppages. The gunner can fire the versatile M249 machine gun from the shoulder, hip, or underarm; with a bipod; or with a tripod.
Figure 1-1. M249 machine gun, bipod and tripod mounted.

12. COMPONENTS
This is the M249 components and their purposes. The item numbers in the table correspond to the callout numbers in the figure.
Components Purposes
1. Barrel assembly……….Houses cartridges for fire; directs the projectile; supports gas regulator.
2. Heat shield assembly Protects the hand from the hot barrel.
3. Rear sight assembly Adjusts for windage and elevation.
4. Cover and feed mechanism assembly
Feeds linked, belted ammunition. Positions and holds cartridges
in position for stripping, feeding, and chambering.
5. Feed tray assembly Positions belted ammunition for fire.
6. Cocking handle assembly……..Moves on a guide rail fixed to the right side of the receiver. Pulls
moving parts rearward.
7. Buttstock and buffer assembly…Folding buttplate and shoulder rest enhance aiming and firing.
Hydraulic buffer absorbs recoil.
8. Bolt assembly……….Feeds, strips, chambers, fires, and extracts round. Powered by
projectile gasses.
9. Slide assembly………..Houses firing pin and roller assembly.
10. Return rod and transfer mechanism assembly……….Absorbs recoil for bolt and operating
rod assembly at the end of recoil movement.

13. 11. Receiver assembly..............Supports all major components, houses the action, and, by use
of cams, controls weapon function.
12. Trigger mechanism Controls fire. Grip has storage for lubricant.
13. Handguard assembly Thermal insulation protects against temperature extremes;
assembly houses cleaning equipment.
14. Sling and snap hook assembly…………Simplifies carriage of weapon.
15. Bipod……….Supports gun in prone position. Legs telescope to three lengths.
16. Gas cylinder assembly Locks bipod and allows gasses to escape.
17. Piston assembly Holds bolt and slide assemblies and houses return spring.
18. Return spring……….Locks bolt, slide, and piston during counter recoil.

14. M249 Disassembly
Pull the upper retaining pin at the rear of the receiver to the left. Allow the buttstock to pivot downward and place it on a surface to support the weapon for disassembly.

15. M249 Disassembly
Pull the operating rod and spring from the receiver group and separate the parts.
Pull the cocking handle to the rear to release the bolt

16. M249 Disassembly Separation of the operating rod group.
Remove the barrel from the receiver.
# 1 Press Barrel release
# 2 Lift slightly up on
barrel
# 3 Slide Barrel forward

17. M249 Disassembly
Remove the collar.
Remove the Gas Regulator.

18. M249 Disassembly
Remove of the handguard if present, depends on variant.
Remove of the buttstock and buffer assembly and Trigger Mechanism.

19. M249 Disassembly
Remove the gas cylinder.
Remove of the bipod.

20. Reverse disassembly steps.
M249 Assembly
Reverse disassembly steps.

21. M240B
The M240B is a general-purpose machine gun. It mounts on a bipod, tripod, aircraft, or vehicle. It is belt fed, air cooled, gas operated, and fully automatic. It fires from an open bolt. Ammunition feeds from a 100-round bandoleer with disintegrating links. The gas from firing one round provides the energy to fire the next one. Thus, the gun fires automatically as long as it has ammunition and the gunner holds the trigger is held to the rear. As the gun fires, the links separate and eject from the side. Empty cases eject from the bottom.

22. Components and Purpose
1. Barrel assembly… olds the cartridge and directs the projectile. Includes the barrel,
flash suppressor, carrying handle, heat shield, front sightassembly, and gas-regulator plug.
2. Heat shield…assembly Protects the gunner’s hand from a hot barrel.
3. Buttstock and buffer assembly; and buffer and spade-grip assembly…
Houses a buffer whose inner spring washers absorb recoil.
4. Receiver assembly…Supports all major components (receiver, handguard, bipod, and
rear sight assembly) and action; uses cams to control function of weapon.
5. Handguard assembly (not shown)…Insulation protects gunner’s hands from heat and cold.
6. Cocking handle assembly…Pulls moving parts rearward along a rail fixed to the right side of
the receiver.
7. Trigger housing assembly…Controls fire.
8. Sling and snap hooks…Simplifies carrying the weapon.
9. Bipod…Supports the M240B barrel in prone position.
10. Drive spring rod assembly…Forces the bolt and operating rod assembly back to firing position.
11. Bolt and operating rod assembly…Feeds, strips, chambers, fires, extracts, and ejects cartridges using propellant gasses for power.
12. Cover assembly…Feeds linked belt, and positions and holds cartridges while the
bolt and operating rod assembly strips, feeds, and chambers them. Has a sight mounting rail on the top exterior.
13. Feed tray…Guides cartridges into chamber. Slotted top allows air to circulate
around (and thus cool) the barrel.
15. Ejection port Guides ejecting cartridges out of the weapon

23. M240

24. Remove the Driving Spring Rod Assembly
M240 Disassembly
Remove the Buttstock
Remove the Driving Spring Rod Assembly

25. Remove the Bolt and Operating Rod Assembly
M240 Disassembly
Remove the Bolt and Operating Rod Assembly
Remove the Trigger Housing Assembly

26. Remove the Cover Assembly
M240 Disassembly
Remove the Cover Assembly

27. Remove the Barrel Assembly
M240 Disassembly
Remove the Barrel Assembly

28. Disassemble the Barrel Assembly
M240 Disassembly
Disassemble the Barrel Assembly

29. Reverse disassembly steps.
M240 Assembly
Reverse disassembly steps.

30. M69 Practice Hand Grenade

31. HAND GRENADE GRIPPING PROCEDURES
The importance of properly gripping the hand grenade cannot be overemphasized. Soldiers must understand that a grenade not held properly is difficult to arm. Sustainment training is the key to maintaining grip efficiency. Holding the grenade in the throwing hand with the safety lever placed between the first and second joints of the thumb provides safety and throwing efficiency. Gripping procedures differ slightly for right- and left-handed Soldiers. Remember acquire target hold the spoon, pull safety clip off, pull pin, then throw!

32. Right-handed Soldiers
Right-handed Soldiers hold the grenade upright with the pull ring away from the
palm of the throwing hand so that the pull ring can be easily removed by the index or
middle finger of the free hand (Figure 3-3).

33. Left-handed Soldiers
Left-handed Soldiers invert the grenade with the fingers and thumb of the
throwing hand positioned in the same manner as by right-handed personnel (Figure 3-4).

34. Prone-to-standing throwing position

35. Prone-to-kneeling throwing position

36. Alternate prone throwing position

37. Guidance
Recommendation
Arrive USMA for competition able to understand the US Army terminology in order to effectively receive hands-on training from the US Army Reserve Soldiers.
Any additional questions can be directed to the attached Brigade Tactical Dept LNO.
Questions?