MOS 0331
Encyclopedia
MOS 0331 is the U.S. Marine Corps
infantry
specialty for crew-served machine gun
s. A machine gun team can use a medium machine gun (M240G), a heavy machine gun (M2), or an automatic grenade launcher
(MK-19
). A machine gun crew is trained in the maintenance
, first echelon (viz, non-technical) repair, and deployment of these guns. When assigned to a unit (either a rifle company or a weapons company
), the machine gunner team will deploy either the medium machine gun or the heavy machine gun (M2 or Mk-19), respectively.
A machine gun is only as effective as its crew, and the teamwork of the crew will determine its utility.
Machine gunners have to memorize the acronym PICMDEEP, which stands for the Eight Principles of Machine Gun Employment:
Machine gun teams consist of 3 Marines: Team Leader, Gunner, and Ammo Man. A machine gun squad
consist of 2 teams led by a Sergeant
. A machine gun section consist of 3 squads led by a Staff Sergeant
in a weapons platoon
.
There are some basics tactics of engaging the enemy, and they depend on the terrain, the target and its orientation (viz, presentation), and overall situation. To be effective, the resultant gunfire, or 'fire', must be distributed over an entire target. Improper distribution results in gaps between areas of engagement (beaten zones) and allows some of the enemy to return fire effectively, or it allows the enemy to simply physically escape.
List of specific methods of engagement:
The searching method of engagement is used to engage targets arrayed in depth. The gunner moves the beaten area through the target area by increases and decreases in range. The searching method is used to engage area targets moving toward or away from the firer.
The traversing method of engagement is used to engage area targets along their front or length. The gunner moves the beaten area across the length of the target. The traversing method is also used to engage area targets moving across the sector of fire.
The z-pattern method of engagement is preferred for dismounted troops. Use both the searching and traversing engagement techniques to cover large or dispersed area targets.
BURST-ON-TARGET (BOT) METHOD OF ADJUSTMENT
The BOT method is the fastest method of adjustment. The gunner moves the strike of the round to the target by adjusting the sight picture. BOT is primarily used with the MK 19 machine gun. To use the BOT method, the gunner fires his sensing rounds or burst, observes the strike of the round while maintaining his initial point of aim, makes the adjustments to his point of aim necessary to move the strike of the round to the target, and then fires a killing burst. The gunner continues to adjust and fire killing bursts until the target is destroyed or the commander announces "CEASE FIRE."
Weapon System Burst Technique
M60/M240B 6- to 9-round killing burst.
Suppress the area with 20- to 30-round bursts, (searching, traversing, or Z-pattern method).
M2 HB 5- to 7-round killing burst.
Suppress the area with 10- to 15- round bursts (searching, traversing, or Z-pattern method).
MK 19 1- to 2-round sensing burst.
Suppress the area with 6-round bursts.
Engage point targets using direct-fire adjustment techniques for both stationary and moving targets.
The methods of direct-fire adjustment are BOT, TOT, target form, and mil change. The machine gun crew can quickly adjust, hit, and destroy the target using any of these adjustment techniques.
Engage moving targets using the BOT method of adjustment. The gunner fires the sensing burst, continuing to track the target and maintain the point of aim until he senses the rounds impacting. Once he has observed the strike of the sensing round, he makes his adjustment and fires a killing burst, maintaining his adjusted point of aim until the round impacts. He then continues to adjust and track the target until the target is destroyed.
When engaging a target that is moving in a lateral direction of the gun, the gunnery must lead (aim in front of) the target to compensate for the movement. The amount of lead depends on the velocity of the ammunition, target speed, and target angle. Applying the proper lead to a moving target will dramatically increase the chance of getting target effects with the first burst.
) machine guns
Automatic grenade launcher (MK 19
)
When engaging targets moving toward or away from the position, the gunner may need to make a small vertical adjustment. If the target is approaching, the gunner aims at the center base of visible mass. If the target is fleeing, the gunner aims at the top center of visible mass.
When a moving vehicle (usually a HMMWV) is firing over its side at a stationary target, lateral motion affects the projectiles as they leave the muzzle. This lateral motion must be compensated for, and the gunner must 'lead' the target. When firing over the left side of the vehicle, the gunner must aim to the left of the target's center of mass. When firing over the right side of the vehicle, the gunner must aim to the right of the target's center of mass.
If the HMMWV and the target are parallel and moving in the same direction, no lead is required. The lateral motion of the projectiles compensates for any lead requirements. If the HMMWV and the target are parallel but moving in opposite directions, target lead is required.
ENGAGEMENT TECHNIQUES FOR AERIAL TARGETS
Aerial targets should be engaged only in self-defense or on order, because stray bullets can hit non-military targets, which could have negative strategic implication (see the strategic corporal). If an aerial target must be engaged, the gunner should aim slightly above the nose of the approaching aircraft, and fire a continuous burst. The gunner does not track the target, but continues to fire until the target passes through the cone of fire. The MK 19 should be used to engage only hovering helicopter targets.
FOOTBALL FIELD METHOD
The football field method is used to engage fast-moving, low-altitude aircraft with all small caliber weapons. The gunner aims approximately two football field lengths in front of the target and fires a long burst until the target leaves the effective range.
REFERENCE POINT METHOD
The reference point method is used to place a high volume of fire on a single point, normally used as a section or platoon method of engagement. The gunner aims at a specific reference point and, on order, fires a long, continuous burst until the target passes through the reference point or is destroyed.
M2- Belt-fed, air-cooled, recoil-operated, capable of firing fully automatic or single shot, fired from the closed bolt position, fired on a M3 tripod and is a crew served weapon.
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
infantry
Infantry
Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...
specialty for crew-served machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
s. A machine gun team can use a medium machine gun (M240G), a heavy machine gun (M2), or an automatic grenade launcher
Grenade launcher
A grenade launcher or grenade discharger is a weapon that launches a grenade with more accuracy, higher velocity, and to greater distances than a soldier could throw it by hand....
(MK-19
Mk 19 grenade launcher
The Mk 19 Grenade Launcher is a 40 mm belt-fed automatic grenade launcher or grenade machine gun that entered U.S. military service during the Cold War, first seeing action during the Vietnam War and remaining in service today.-Overview:...
). A machine gun crew is trained in the maintenance
Maintenance, Repair and Operations
Maintenance, repair, and operations or maintenance, repair, and overhaul involves fixing any sort of mechanical or electrical device should it become out of order or broken...
, first echelon (viz, non-technical) repair, and deployment of these guns. When assigned to a unit (either a rifle company or a weapons company
Weapons company
A weapons company, sometimes called a manoeuvre support company is a company-sized military unit attached to an infantry battalion to support the rifle companies of the battalion...
), the machine gunner team will deploy either the medium machine gun or the heavy machine gun (M2 or Mk-19), respectively.
Teams
Machine gunners have to memorize the acronym PICMDEEP, which stands for the Eight Principles of Machine Gun Employment:
- P – Pairs
- Always deploy in pairs. Not only in combat, but in all aspects of military accountability.
- I - Interlocking fields of fire
- When deploying your weapon, always interlock your fields of fire with respect to your teammate (since you have deployed in pairs, you have a teammate).
- C – Coordinated fires
- Always coordinate your fire with your teammate, so as to conserve ammo and to increase confusion upon the enemy.
- M – Mutual support
- Support your teammate by picking up your rate of fire if they are out of ammo or have a malfunction of their weapon.
- D – Defilade fire
- Fire in defilate (from below the horizon) so as to cover your position and protect your position from direct fire from the enemy.
- E – Enfilade fire
- Use enfilade fire to maximize damage of your fires. Enfilade fire is when your rounds (which fall in an oval with the long axis parallel to your direction towards the enemy) fall within the long axis of the enemy (since machine gunning is not designed to engage single individuals, this relates to the long axis of the group of combatants or the vehicle or building).
- E – Economy of fires
- Conserve your ammunition and use only the appropriate amount of ammunition for the target, taking into account what ammunition you have and the particulars of your situation.
- P – Protection
- One member of the machine gun crew will post as rear security to watch the gunner's and team leader's blind spot. The machine gun position will also use cover and concealment to protect the crew from fire and hide them from observation.
Machine gun teams consist of 3 Marines: Team Leader, Gunner, and Ammo Man. A machine gun squad
Squad
In military terminology, a squad is a small military unit led by a non-commissioned officer that is subordinate to an infantry platoon. In countries following the British Army tradition this organization is referred to as a section...
consist of 2 teams led by a Sergeant
Sergeant
Sergeant is a rank used in some form by most militaries, police forces, and other uniformed organizations around the world. Its origins are the Latin serviens, "one who serves", through the French term Sergent....
. A machine gun section consist of 3 squads led by a Staff Sergeant
Staff Sergeant
Staff sergeant is a rank of non-commissioned officer used in several countries.The origin of the name is that they were part of the staff of a British army regiment and paid at that level rather than as a member of a battalion or company.-Australia:...
in a weapons platoon
Platoon
A platoon is a military unit typically composed of two to four sections or squads and containing 16 to 50 soldiers. Platoons are organized into a company, which typically consists of three, four or five platoons. A platoon is typically the smallest military unit led by a commissioned officer—the...
.
Methods of engagement
The crew’s goal is to hit a target and destroy it as fast as possible. Proper engagement techniques will allow the crew to place enough fire on the target to destroy it. Machine gun techniques are generally the same for the M2 HB, M60/M240B, and MK 19 machine guns.There are some basics tactics of engaging the enemy, and they depend on the terrain, the target and its orientation (viz, presentation), and overall situation. To be effective, the resultant gunfire, or 'fire', must be distributed over an entire target. Improper distribution results in gaps between areas of engagement (beaten zones) and allows some of the enemy to return fire effectively, or it allows the enemy to simply physically escape.
List of specific methods of engagement:
- SEARCHING METHOD
The searching method of engagement is used to engage targets arrayed in depth. The gunner moves the beaten area through the target area by increases and decreases in range. The searching method is used to engage area targets moving toward or away from the firer.
- TRAVERSING METHOD
The traversing method of engagement is used to engage area targets along their front or length. The gunner moves the beaten area across the length of the target. The traversing method is also used to engage area targets moving across the sector of fire.
- Z-PATTERN METHOD
The z-pattern method of engagement is preferred for dismounted troops. Use both the searching and traversing engagement techniques to cover large or dispersed area targets.
Methods of Adjustment
Adjustments may be made before or after firing. Machine gun fire is adjusted by observing the strike of the round, observing the flight of tracers, re-laying frequently, or by a combination of these. The use of tracer ammunition provides a means of adjusting fire. At night, it aids in illuminating the objective area and has a demoralizing effect on the enemy. Observation and adjustment of fire is the most important and is continuous throughout the action. The gunner is trained to observe and adjust fire without command and to check the lay of the gun frequently.BURST-ON-TARGET (BOT) METHOD OF ADJUSTMENT
The BOT method is the fastest method of adjustment. The gunner moves the strike of the round to the target by adjusting the sight picture. BOT is primarily used with the MK 19 machine gun. To use the BOT method, the gunner fires his sensing rounds or burst, observes the strike of the round while maintaining his initial point of aim, makes the adjustments to his point of aim necessary to move the strike of the round to the target, and then fires a killing burst. The gunner continues to adjust and fire killing bursts until the target is destroyed or the commander announces "CEASE FIRE."
Weapon System Burst Technique
M60/M240B 6- to 9-round killing burst.
Suppress the area with 20- to 30-round bursts, (searching, traversing, or Z-pattern method).
M2 HB 5- to 7-round killing burst.
Suppress the area with 10- to 15- round bursts (searching, traversing, or Z-pattern method).
MK 19 1- to 2-round sensing burst.
Suppress the area with 6-round bursts.
Techniques for different targets
- POINT TARGETS
Engage point targets using direct-fire adjustment techniques for both stationary and moving targets.
The methods of direct-fire adjustment are BOT, TOT, target form, and mil change. The machine gun crew can quickly adjust, hit, and destroy the target using any of these adjustment techniques.
- MOVING TARGETS
Engage moving targets using the BOT method of adjustment. The gunner fires the sensing burst, continuing to track the target and maintain the point of aim until he senses the rounds impacting. Once he has observed the strike of the sensing round, he makes his adjustment and fires a killing burst, maintaining his adjusted point of aim until the round impacts. He then continues to adjust and track the target until the target is destroyed.
When engaging a target that is moving in a lateral direction of the gun, the gunnery must lead (aim in front of) the target to compensate for the movement. The amount of lead depends on the velocity of the ammunition, target speed, and target angle. Applying the proper lead to a moving target will dramatically increase the chance of getting target effects with the first burst.
Techniques for different weapons
Heavy (M2) and medium (M240/M60M60 machine gun
The M60 is a family of American general-purpose machine guns firing 7.62×51mm NATO cartridges from a disintegrating belt of M13 links...
) machine guns
- Lead slow or fast moving targets at less than 700 meters by one target form.
- Lead fast moving targets at 700 meters or greater by two target forms.
Automatic grenade launcher (MK 19
Mk 19 grenade launcher
The Mk 19 Grenade Launcher is a 40 mm belt-fed automatic grenade launcher or grenade machine gun that entered U.S. military service during the Cold War, first seeing action during the Vietnam War and remaining in service today.-Overview:...
)
- Lead slow moving targets less than 600 meters by one target form.
- Lead slow moving targets at 600 meters or greater by two target forms.
When engaging targets moving toward or away from the position, the gunner may need to make a small vertical adjustment. If the target is approaching, the gunner aims at the center base of visible mass. If the target is fleeing, the gunner aims at the top center of visible mass.
When a moving vehicle (usually a HMMWV) is firing over its side at a stationary target, lateral motion affects the projectiles as they leave the muzzle. This lateral motion must be compensated for, and the gunner must 'lead' the target. When firing over the left side of the vehicle, the gunner must aim to the left of the target's center of mass. When firing over the right side of the vehicle, the gunner must aim to the right of the target's center of mass.
If the HMMWV and the target are parallel and moving in the same direction, no lead is required. The lateral motion of the projectiles compensates for any lead requirements. If the HMMWV and the target are parallel but moving in opposite directions, target lead is required.
ENGAGEMENT TECHNIQUES FOR AERIAL TARGETS
Aerial targets should be engaged only in self-defense or on order, because stray bullets can hit non-military targets, which could have negative strategic implication (see the strategic corporal). If an aerial target must be engaged, the gunner should aim slightly above the nose of the approaching aircraft, and fire a continuous burst. The gunner does not track the target, but continues to fire until the target passes through the cone of fire. The MK 19 should be used to engage only hovering helicopter targets.
FOOTBALL FIELD METHOD
The football field method is used to engage fast-moving, low-altitude aircraft with all small caliber weapons. The gunner aims approximately two football field lengths in front of the target and fires a long burst until the target leaves the effective range.
REFERENCE POINT METHOD
The reference point method is used to place a high volume of fire on a single point, normally used as a section or platoon method of engagement. The gunner aims at a specific reference point and, on order, fires a long, continuous burst until the target passes through the reference point or is destroyed.
Characteristics
M240B- Belt-fed, air-cooled, gas-operated, fully automatic medium machine gun, fired from the open bolt position, fired on bi-pod or M-122 tri-pod and is a crew served weapon.M2- Belt-fed, air-cooled, recoil-operated, capable of firing fully automatic or single shot, fired from the closed bolt position, fired on a M3 tripod and is a crew served weapon.
External links
- INTRO TO MACHINE GUN EMPLOYMENT, Quanitco, Officer's course.