Heavy Machineguns

Question 1

What are the sights graduated on the M2?

Answer 1

100-2600 yards

0-62 mils

Question 2

What is the weight of the M2?

Answer 2

Receiver - 60 lbs
Barrel - 24 lbs
Tripod - 44 lbs
* Total - 128 lbs

Question 3

What are the rates of fire for the M2?

Answer 3

Sustained - < 40 rpm
Rapid - >= 40 rpm
Cyclic - 450 - 550 rpm

Question 4

What is the muzzle velocity of the M2?

Answer 4

3050 fps

Question 5

What are the ranges for the M2?

Answer 5

Maximum - 7400m
Maximum effective - 1830m
Grazing - 700m

Question 6

What are the different types of ammo for the M2?

Answer 6

• M2 Dummy (Natural, holes in cartridge)
• M1, M1A1 Blank (Crimped)
• M2, M33 Ball (Natural)
• M1, M23 Incendiary (Blue tip)
• M1, M10, M17 Tracer (Red, orange, or brown tip)
• M2 Armor Piercing (Black)
• M8 Armor Piercing Incendiary (Aluminum tip)
• M20 Armor Piercing Incendiary Tracer (Aluminum tip with red ring)
• M903 Sabot Light Armor Penetrator (SLAP) (Amber tinted round)
• M962 Sabot Light Armor Penetrator (SLAP) Tracer (Red tinted round)

Question 7

What are the major components of the M2?

Answer 7

• Barrel group
• Carrier assembly
• Backplate group
• Cover group
• Bolt group
• Receiver group
• Bolt stud
• Barrel extension group
• Barrel buffer body
• Driving spring rod assembly

Question 8

Know the 4 conditions for the M2…

Answer 8

…

Question 9

Condition 2 is known as (for the M2)?

Answer 9

Half Load

Question 10

Condition 1 is known as (for the M2)?

Answer 10

Full Load

Question 11

What are examples of common malfunctions for the M2?

Answer 11

• Failure to function freely

- Uncontrolled automatic fire

Question 12

If using RBC to clean a weapon, you should use which three types of lubricants?

Answer 12

• Lubricating Oil Semfluid (LSA)
• Lubricating oil, special purpose (PL-S)
• Lubricating oil, general purpose (PL-M)

Question 13

What is headspace?

Answer 13

The distance between the face of the bolt and the base of the cartridge case, fully seated in the chamber.

Question 14

What is timing?

Answer 14

The adjustment of the gun so that the firing takes place when the recoiling parts are in the correct position for firing.

Question 15

How far do the recoiling parts need to be out of battery to prevent contact between the front end of the barrel extension and trunnion block?

Answer 15

.020 and .116 inches