MG Employment Flashcards
Which FM’s cover machine gun employment?
FM 3-22.68
FM 3-21.8
Describe cone of fire
Each round fired in a burst will have a different trajectory. The pattern created is called cone of fire
What is the beaten zone?
Elliptical pattern formed on the ground on the target by the striking rounds
What is danger space?
Space between machine gun and target where trajectory rises less than 1.8m above ground
What are the 3 classes of fire?
Respect to the ground, respect to the gun, respect to the target
What are the 2 sub categories of “respect to ground”?
Grazing fire: when center of cone of fire is less than 1 meter above ground.
Plunging fire: when danger space is within the beaten zone
What are the 6 subcategories of respect to gun?
Fixed Traversing Searching Free gun Search and traverse Swinging traverse
What are the 4 subcategories of respect to target
Frontal fire
Flanking fire
Oblique fire
Enfilade fire
What is overhead fires?
Only delivered from tripod or vehicle using T and E and friendlies between 350m -850m
What are the 6 methods of fire control?
Pre-arranged signals Range cards Personal contact Verbal Hand / arm signals SOP’s
What is a defilade position?
When the machine gun and crew are completely masked by terrain from enemy
What are the 6 fire commands?
Alert Direction Description Range Method of fire Command to open fire
What is the sustained rate of fire for the M249?
50 rounds / min 3-5 round burst
What is the sustained rate of fire for the M240B?
100 rounds/min 6-9 round burst
What is the sustained rate of fire for the M60?
100 rounds/min 6-9 round burst
How often is barrel change for sustained rate of fire?
Every 10min
What is the rapid rate of fire for the M249?
100 rounds /min 6-8 round burst
What is the rapid rate of fire for the M240B?
200 rounds / min 10-12 round burst
What is the rapid rate of fire for the M60
200 rounds /min 10-12 round burst
How often is the barrel change for rapid fire?
Every 2 min
What is the cyclic rate of fire for the M249?
850 rounds/min
What is the cyclic rate of fire for the M240B?
650-950 rounds/min
What is the cyclic rate of fire for the M60?
550 rounds/min
How often is the barrel change for cyclic fire?
Every 1 min
What us the DA form for the range card?
DA form 5517
What is final protective fire?
An immediate prearranged barrier of fire to stop enemy movement across defense lines or areas
What is final protective line?
Predetermined line along which grazing fire is placed to stop enemy assault. Fixed in direction and elevation
What is dead space?
Areas where a soldier is waist high to line of sight of gunner
What is maximum ordinate?
The highest point above the line of sight the trajectory reaches between the muzzle of the weapon and the base of the target
What is trajectory?
Is the curved path of the projectile in its flight from the muzzle of the weapon to its impact
What is the appropriate fire for point targets?
Fixed fire
What is the appropriate fire for area targets?
Traverse and search fire
What is the appropriate fire for linear targets?
Traversing fire
What is the appropriate fire for deep targets?
Searching fire
What is the appropriate fire for linear targets with depth?
Traverse and search fire
2 techniques for air defense
Football field- fast mover 2 fields. Slow mover 1/2 field.
Reference point
Whats PDF
Covers area with good fields of fire or likelihood of dismounted approach
3 keys of overhead fires
Coordination
Communication
Situational awareness
3 assault firing positions
Hip
Under arm
Shoulder fire
M192 tripod ( light)
Elevation
Traverse
Full handle manipulation
Elevation- 0-530 mils
Traverse 0-900 mils
Full handle manipulation 5 mils
M122 tripod (heavy) T and E graduated T and E scale valve Traverse hand wheel Elevation hand wheel Elevation bar
T and E graduated- 5 mil increments
T and E scale valve - left 100-450 right 100-425 total 875 mils
Traverse hand wheel- 100 mils
Elevation hand wheel- 50 mils
Elevation bar- up 200 down 200. 400 mils total
Gunners rule
At least 350m in front of gun range to target 850m or less set gun to proper range without disturbing lay of gun, set rear sight to 1600m. New line of aim is troop safety limit
3 types of wire obstacles
Protective wire- out of defensive trace and grenade range
Tactical - friendly side of FPL give enfilade
Supplementary- disguise channelize enemy into tactical wire
3 sectors of fire
Primary- main sector of fire
Alternate- different position, same sector of fire
Supplementary- different position, different sector
8 principles of employment
PICMDEEP
Pairs Interlocking fires Coordinated fires Mutual support Defilade Enfilade Economy Protection
5 characteristics of fire
Trajectory Max ordinate Cone of fire Beaten zone Danger space
