Machine Guns

Question 1

Sustained Rate of fire

M249

Answer 1

50 rounds/ minute
3 to 5 round bursts every 4-5 seconds
Barrel change every 10 minutes

Question 2

Rapid Rate of fire M249

Answer 2

100 rounds/ minute
8 to 10 round bursts every 2-3 seconds
Barrel change every 2 minutes

Question 3

Cyclic Rate of fire M249

Answer 3

650-850 rounds/ minute

Barrel change every 1 minute

Question 4

Maximum range of M249

Answer 4

3600 m

Question 5

Max effective range of M249

Answer 5

1000 m

Question 6

Max effective ranges: Area and Point on tripod, M249

Answer 6

Area: 1000 m
Point: 800 m

Question 7

Max effective ranges: Area and Point on bipod, M249

Answer 7

Area: 800 m
Point: 600 m

Question 8

Sustained rate of fire M240B

Answer 8

100 rounds/ minute
6 to 9 round bursts every 4-5 seconds
Barrel change every 10 minutes

Question 9

Rapid rate of fire M240B

Answer 9

200 rounds/ minute
10 to 13 round bursts every 2-3 seconds
Barrel change every 2 minutes

Question 10

Cyclic rate of fire M240B

Answer 10

650-950 rounds/ minute

Barrel change every 1 minute

Question 11

Maximum range of M240B

Answer 11

3725 m

Question 12

Max effective range of M240B

Answer 12

1100 m

Question 13

Max effective ranges: Area and Point on tripod, M240B

Answer 13

Area: 1100 m
Point: 800 m

Question 14

Max effective ranges: Area and Point on bipod, M240B

Answer 14

Area: 800 m
Point: 600 m

Question 15

Maximum Ordinate

Answer 15

Highest point of bullet trajectory between muzzle and target- about 2/3 distance from weapon to target

Question 16

Cone of fire

Answer 16

How each round follows a slightly different trajectory, creating a cross sectional area where rounds travel

Question 17

Beaten zone and how it changes w/ range and slope

Answer 17

Elliptical pattern formed on the ground by striking rounds
Short range/Downward slope- lengthens
Long range/Upward slope- shortens

Question 18

Danger space

Answer 18

Space between gun and target where rounds rise less than 1.8 meters above ground

Question 19

Grazing fire

Answer 19

Where the center of the cone of fire rises less than 1 meter above ground

Question 20

Plunging fire

Answer 20

When the danger space occurs exclusively within the beaten zone; when firing at long ranges or on sloping terrain

Question 21

Frontal fire

Answer 21

When the long axis of the beaten zone is at a right angle to the front of the target

Question 22

Flanking fire

Answer 22

Firing at the side of a target

Question 23

Oblique fire

Answer 23

When the long axis of the beaten zone is at an angle other than perpendicular to the front of the target

Question 24

Enfilade fire

Answer 24

When the long axis of the beaten zone coincides with the long axis of the target, can be frontal or flanking

Question 25

Fixed fire

Answer 25

Where depth and width of beaten zone covers the target- one aiming point

Question 26

Traversing fire

Answer 26

Changing direction left or right

Question 27

Searching fire

Answer 27

Changing elevation- firing further or closer

Question 28

Traversing and searching fire

Answer 28

Changing direction and elevation

Question 29

Free gun

Answer 29

Rapid changes in direction and elevation- not accomplished w/ T&E

Question 30

Sector of fire

Answer 30

Target area

Question 31

Final Protective Fire- FPF

Answer 31

Immediately available, prearranged barrier of fire- prevents enemy movement across defensive lines

Question 32

Final Protective Line- FPL

Answer 32

Predetermined line along which grazing fire is placed to stop an enemy assault- gun sights along FPL unless engaging other targets- part of unit FPF

Question 33

Primary Direction of Fire- PDF

Answer 33

Main direction of fire

If an FPL is not given, becomes part of FPF

Question 34

M192 Tripod traverse

Answer 34

900 mils (50.6 degrees)

Question 35

PICMDEEP

Answer 35

Pairs
Interlocking sectors
Coordinated fires
Mutual support (talking guns)
Defilade- emplacement
Enfilade- desired firing
Economy of Fire
Protection