M2 .50 CALIBER MACHINE GUN PMI

INSTRUCTORS:

REFERANCES: FM 23-65

PHASE 1

• General description

• Types of ammunition

• Clearing

• Disassembly, assembly

• Operation and functioning

• Performance problems

PHASE 2

1. Fundamentals

A. Firing positions

B. Dry fire exercise

C. Range setting and layout

D. Traverse and elevation mechanism

E. Range determination

F. Observation and adjustment fire

2. Fire commands

GENERAL DESCRIPTION

THE BROWNING MACHINE GUN CALIBER .50; M2 IS A BELT FED, RECOIL OPERATED, AIR COOLED, CREW SERVED,

MACHINE GUN. THE GUN IS CAPABLE OF SINGLE SHOTAS WELL AS AUTOMATIC FIRE, AND OPERATES ON THE

SHORT RECOIL PRINCIPLE

GENERAL DESCRIPTION

WEIGHT 84 POUNDSWEIGHT OF BARREL 24 POUNDSGUN LENGTH 65.13 INCHESBARREL LENGTH 45 INCHESLENGTH OF RIFLING 41.88 INCHESNUMBER OF LANDS AND GROOVES 8 TWIST, RIGHT HAND ONE TURN/15 INCHESFEED LINK BELTOPERATION RECOILCOOLING AIRMUZZLE VELOCITY 3,050 FEET/SECONDRATE OF FIRE 450-550 ROUNDS/MINUTEMAX RANGE 7,440 YARDSMAX EFF. RANGE 2,000 YARDS AREA TARGET 1,830 METERS POINT TARGET 1,500 METERS

COMPONENTS OF THE .50 CAL.

1. Barrel group – houses cartridges for firing; directs projectile

2. Carrier assembly – provides handle to carry barrel and to remove barrel from the receiver

3. Backplate group – houses the trigger, blot latch release, buffer tube sleeve, and the left and right spade guides

4. Receiver group – serves as a support for all major components; houses action of weapon, which controls functioning of weapon

5. Bolt group – provides feeding, chambering, firing, and extracting, using the propellant gases and recoil spring for power

6. Cover group – feeds linked belt ammunition; positions and holds cartridges in position for extracting, feeding, and chambering

7. Bolt stud – provides a means to move the bolt to the rear with the retracting slide handle

COMPONENTS CONT.

8. Barrel extension group – secures the barrel to the recoiling parts

9. Barrel buffer body – assists in recoil and counterrecoil of the bolt group

10. Driving spring rod assembly – drives the bolt forward when the bolt latch release is depressed

TYPES OF AMMUNITION

AMMUNITION CONT.

1. Ball – for use in marksmanship training, and against personnel and light material targets

2. Tracer – to aid in observing fire. Secondary purposes are for incendiary effect and for signaling

3. Armor piercing – for use against armored aircraft and lightly armored vehicles, concrete shelters, and other bullet-resisting targets

4. Incendiary – for incendiary effect, especially against aircraft

5. Armor piercing incendiary – for combined armor piercing and incendiary effect

6. Armor piercing incendiary tracer- same as above just with additional tracer feature

7. Blank - for simulated fire (contains no bullet)

8. High pressure test – for use only in proof firing of weapons and barrel

9. Dummy – for training (completely inert)

Clearing The Weapon

DISASSEMBLY

1. Barrel group

2. Backplate group

3. Driving spring rod assembly

4. Bolt stud

5. Bolt group

6. Barrel buffer body group and barrel extension group

7. Barrel buffer assembly

REASSEMBLY

1. Barrel buffer assembly and barrel buffer body group

2. Barrel buffer group and barrel extension group

3. Bolt group

4. Bolt stud

5. Driving spring rod assembly

6. Backplate group

7. Barrel group

FUNCTIONS CHECK

1. Place the weapon in single-shot mode

2. Open the cover and lock the bolt to the rear

3. Hold the retractor handles, press the bolt latch release and ride the bolt forward

4. Press down on the trigger; weapon should fire (check T-slot to insure fire pin does protrude)

5. Place weapon in automatic fire mode

6. Pull the retractor slide handle to the rear and hold

7. Release the pressure on the slide handle and ride the bolt forward

8. Make sure firing pin does not protrude

9. Press trigger weapon should fire

10. Make sure firing pin does protrude

OPERATION AND FUNCTIONING

1. Mounting on the M3 tripod

2. Loading

1. Single-shot mode

2. Automatic mode

3. Unloading

1. Ensure weapon is in single-shot mode

4. Cycle of functioning (some of these steps may occur at the same time)

1. Feeding 5. Unlocking

2. Chambering 6. Extracting

3. Locking 7. Ejecting

4. Firing 8. Cocking

OPERATION AND FUNCTIONING CONT.

5. Headspace and timing – headspace is the distance between the face of the bolt and the base of the cartridge case, fully seated in the chamber. Timing is the adjustment of the gun so that firing takes place when the recoiling parts are in the correct position for firing.

1. Gauges – the headspace and timing gauge consists of a headspace gauge and two timing gauges. These gauges provide accurate means of checking the adjustments of headspace and timing.

*check headspace and timing after assembly and after changing barrels*

PERFORMANCE PROBLEMS

1. Malfunctions

1. Failure to function freely

2. Uncontrolled automatic fire

2. Stoppages

1. Failure to feed 5. Failure to unlock

2. Failure to chamber 6. Failure to extract

3. Failure to lock 7. Failure to eject

4. Failure to fire 8. Failure to cock

3. Immediate action

4. Remedial action

MARKSMANSHIP FUNDAMENTALS

BASIC FUNDAMENTALS

A. STEADY POSITION

B. SIGHTING

C. AIMING

D. DETERMINING RANGE

E. MANIPULATING THE T&E MECHANISM

FIRING POSITIONS

•PRONE – overview, full contact to the ground behind the gun with the elbows on the ground.

•SITTING WITH TRIPOD- the gunner sits directly behind the gun between the legs under the tripod or cross them, depending on his physique. The elbows on the inside of his thighs to get the best support

•STANDING WITH TRIPOD- standing directly behind the gun with his feet spread a comfortable position

DRY FIRE EXERCISE

1. Sighting and aiming

2. Range setting and laying

3. Traverse and elevation manipulation

4. Range determination

5. Observation and adjustment to fire

Sighting and aiming

The first step in proper sighting is finding a natural, comfortable spot. Second step in sighting is to move the weapon until the top center of the front sight blade through the rear peep sight. The third step is to establish correct sight picture

Range setting and laying

Accurately setting the leaf sight- the gunner will then raise and set his sights, and align the weapon on the aim point. When the gunner completes this task, he will announce “UP”

TRAVERSE AND ELEVATION MANIPULATION

1. T&E- manipulation of the T&E mechanism is a key factor in effectively engaging targets

2. The traversing mechanism consists of a traversing hand wheel, locking nut, scale and yoke.

3. Elevating mechanism consists of an upper and lower elevating screw.

4. The elevating hand wheel is graduated in 1 mil increments.

5. Direction and elevation readings constitute the data necessary to engage preselected target areas during limited visibility

Range determination

1. Methods of determination of distances and sizes

2. Ranges are determined to the nearest 100meters for the machine gun firing.

3. For targets that appear to be more than 500 meters, the gunner must modify this technique.

4. Terrain affects the appearance of 100 meter units of measure.

5. The appearance of objects method may be used if the gunner is unable to use the 100 meter unit of measure method because of the terrain.

Observation and adjustment to fire

1. Observation is used when firing on the 10-meter range because the impact of the round is visible on the target.

2. 1 click on the traverse wheel adjustment at a 10-meter target moves the round ½ inch

3. Field fire- 1 click on the traverse wheel adjustment will move the round ½ inch at 500 meters, 1 inch at 1000 meters

4. The gunner may use the adjusted aiming point method to adjust the fire.

SIX ELEMENTS OF A FIRE COMMAND

ALERT FIRE MISSION

DIRECTION FRONT

DESCRIPTION TROOPS IN OPEN

RANGE ONE HUNDRED

METHOD OF FIRE AT MY COMMAND

COMMAND TO OPEN FIRE FIRE

.50 cal Performance Examination

1. Clear the MG2. Disassemble the MG3. Assemble the MG4. Functions check 5. Maintain the MG6. Headspace on the MG 7. Timing on the MG8. Load the MG 9. Perform immediate action on the MG 10. Unload the MG

SUMMARY

1. General description

2. Types of ammunition

3. Clearing

4. Disassembly, assembly

5. Operation and functioning

6. Performance problems

7. Fundamentals

8. Fire commands