Theory of Machine Gun

DP2 (Infantry Platoon Support Weapons) 7CMBG HQ

Introduction
A. Welcome students to Machine Gunners Indoctrination and ask if they are ready to start.

B. Introduce yourself – Rank & Name and your current assignment within the Unit. Give a brief history of your service with the Unit.

The GPMG C6 Machine Gun
This is an introduction to the GPMG, the team and its supporting role.

The C6 General Purpose Machine Gun (GPMG) is an air-cooled, belt-fed, gas-operated automatic weapon. It is able to provide a heavy, controlled volume of accurate, long-range fire (300-800 meters) that is beyond the capabilities of individual small arms. This makes it a lethal weapon in the right hands.

Roles of the GPMG
The GPMG is a versatile weapon that can support both offensive and defensive operations. It can provide a heavy volume of close, accurate, and continuous fire support to pin down and destroy enemy personnel in support of an attack; it usually kills in one shot. That same heavy volume of fire, when employed as final protective fires, forms an integral part of a unit’s defensive fire plan and can effectively break up and stop an enemy assault.

The machine gun is the infantry platoon’s primary weapon against a dismounted enemy, it has limited effects against lightly armored vehicles but it will cause vehicle crews to button-up and operate with reduced effectiveness. The platoon commander employs his C6 machine guns to provide long range, accurate, sustained fires against infantry, apertures in fortifications, buildings, and lightly armored vehicles and trucks.

The Machine Gun Fire Team
The machine gun team can consist of three personnel. The gunner (no#1), loader (no#2) and gun controller. The gunner is the primary member of the team. The gun controller is in command but all the team’s efforts are focused on the employment of the main team weapon, the GMPG. Therefore the gunner is the most important member of the team. The gun controller is responsible for selecting the firing position, observing and correcting the gunner’s fire, and carrying out the section or platoon commanders commands. The loader carries ammunition for the gunner and acts as security for the team and point man while moving into position. All team members carry Smoke grenades to use for concealment when moving under fire.

Principles of Machine Gun Employment
Maximum efficiency in the tactical employment of all types of machine guns can be reached by applying the following principles during planning:

a. Mutual Support

b. Coordination of Fire.

c. Positioned in Defilade.

d. Positioned to Produce Enfilade Fire

e. Interlocking Fire.

f. Cover and Concealment.

g. Economy.

Firing Positions
Location. The firing position should take advantage of the terrain to ensure the sector of fire assigned is covered. The best positions use hilltops and hillsides and accessible rooftops for height advantage to give the best possible coverage of the sector. In urban areas the position is generally the lowest available to use grazing fire to engage targets.

Accurate Initial Burst
Obtaining an accurate initial burst of fire on the target is fundamental to good marksmanship and the enemy will concentrate his fire on the machine gun once it has been located, therefore initial accuracy is essential. This is accomplished by correctly estimating the range to the target and by correctly setting the sights on the machine gun. The GPMG has two types of sights, simple Iron Sights and the C79 Optical Sight. The C6 iron sights are aligned by viewing through the rear peep aperture and aligning the fore sight blade on the target. The C79 sight is Adjustable from 300-1200 meters. The gunner adjusts his aim by placing the sight on the target and firing short bursts. Breath control is practiced during aiming and firing. Observing the fall of shot the gunner moves the sight until the rounds are impacting on target. Short bursts of 1 to 3 or 3 to 5 rounds provide the greatest initial accuracy.

Rates of Fire
The rapid rate of fire of 200 rounds per minute is delivered in bursts of 10 to 12 rounds, which are fired 2 to 3 seconds apart. The slow rate of fire of 100 rounds per minute is delivered in bursts of six to eight rounds, which are fired 4 to 5 seconds apart. Gunners can use a simple phrase to repeat while firing to time their bursts and achieve an accurate burst count. (Give examples)

Introduction
The gunner’s knowledge of the machine gun cannot be complete until he learns something of the action and effect of the projectiles when fired. This section discusses various characteristics of machine gun fire, including trajectory, cone of fire, and beaten zone.

Trajectory
In ARMA 2 the GPMG is zeroed to 300 meters. The amount of elevation for any given range greater than this is a matter of elevating the sight above the target. Because of this elevation of the axis of the bore, the projectile, when it leaves the muzzle, does not travel in a straight line to the target. It starts on the prolongation of the axis of the bore and rises above the line of aim. Then, under the influence of gravity, and the resistance of the air, the projectile begins to fall, following a curved path until it intersects the line of aim again at the target. The curved path followed by the projectile is called the trajectory.

Cone of Fire
When a burst is fired, the vibrations of the gun give each bullet a trajectory differing slightly from that of the others. The resulting group of trajectories is known as the cone of fire. For the GPMG, at ranges up to 700 meters over level or uniformly sloping ground, the lower bound of the cone of fire does not rise above the height of a standing man (1.8 meters). With each increase in elevation of the gun, there is a further rise of the cone above the ground.

Beaten Zone
The beaten zone is the area on the ground upon which the cone of fire falls.

a. Effect of Slope of Ground. When the cone of fire falls on level ground which is at the same height as the gun, the maximum length is obtained when the slope of the ground approximates the angle of fall of the bursts. On rising ground, the length of the pattern is shortened. The minimum length occurs where the slope of the ground is perpendicular to the cone of fire at the point of impact.

b. Effect of Range. As the range increases, the beaten zone becomes shorter and wider.



Dead Space
Dead space is an area within the maximum range of a weapon which cannot be covered by fire or observation from a particular position because of intervening obstacles, the nature of the ground, the characteristics of the trajectory, or the limitations of the pointing capabilities of the weapon.

Danger Space
This is the area from the muzzle of the gun, out to and including the beaten zone, where a standing man(measured as 1.8 meters tall) will be hit, somewhere on his body, by some part of the cone of fire.

Classes of fires
Machine gun fire is classified with respect to:

The ground.

The target.

The gun.

Classes of Fire with Respect to the Ground
a. Grazing Fire. Fire approximately parallel to the ground where the center of the cone of fire does not rise above 1 meter.

b. Plunging Fire. Fire in which the angle of fall of the rounds, with reference to the slope of the ground, is such that the danger space is practically confined to the beaten zone and the length of the beaten zone is materially shortened.



Classes of Fire with Respect to the Target
a. Frontal Fire. The long axis of the beaten zone is at a right angle to the long axis of the target.

b. Flanking Fire. Delivered against the flank of a target.

c. Oblique Fire. The long axis of the beaten zone is at an angle, but not a right angle, to the long axis of the target.

d. Enfilade Fire. The long axis of the beaten zone coincides or nearly coincides with the long axis of the target.

Classes of Fire with Respect to the Gun
a. Fixed Fire. Fire delivered on a point target.

b. Traversing Fire. Fire distributed against a wide target requiring successive changes in the direction of the gun.

c. Searching Fire. Fire distributed in depth by successive changes in the elevation of the gun.

d. Traversing and Searching Fire. Fire delivered both in width and depth by changes in direction and elevation.

e. Free Gun. Fire delivered against moving targets which must be quickly engaged and which require rapid changes in both direction and elevation

Sectors of Fire
A sector of fire is a section of terrain designated by specific boundaries and covered by fire by the unit to which it is assigned.

Rates of Fire
The greatest surprise and shock effect is obtained by combining the maximum rate of fire with the simultaneous opening of fire of all guns for at least the first few bursts. Fleeting targets are engaged as soon as possible and with the maximum fire available. The initial delivery of fire using the rapid rate facilitates adjustment of fire. When the rate of fire is not specified, the rapid rate is used. In all cases, unless otherwise ordered, the first few bursts are at the rapid rate; thereafter, the prescribed rate is used.

Adjustment of Fire
Fire is adjusted by observation of strike, observation of tracers, and frequently relaying or checking the aim.

a. Initial Adjustment of Fire.

b. Subsequent Corrections and Adjustments.

Distribution of Fire
Fire, to be effective, is distributed over the entire target. Improper distribution results in gaps between beaten zones and allows a part of the enemy to escape or to use his weapons without effective opposition.

Machine Gun Fire Unit
A squad of guns is the machine gun fire unit. Whenever practical, at least two guns are assigned the same mission, although occasions may arise when single guns may profitably be employed.

Manipulation.
Manipulation is the process of moving the machine gun between bursts so that fire is distributed over a wide, deep, or oblique target.

Point Target
Targets having a width or depth no greater than the beaten zone for the ground on which they are located are considered as point targets and are engaged by fixed fire.

Overhead Fires
Overhead fire is fire delivered over the heads of friendly troops. A machine gun on a tripod is capable of delivering this type of fire because of the small and uniform dispersion of the cone of fire. In the attack, the use of overhead fire permits the machine gun to support the advance of rifle units.

NOTE: Overhead fire is not delivered when the gun is mounted on the bipod, unless the vertical interval of the troops below the gun target line is such as to make safety obvious.



Firing on Unarmored and Lightly Armored Vehicles
It is possible to disable and destroy lightly armored vehicles and trucks. However these targets can require a large amount of ammunition so should only be targets if either they engage you or all accompanying enemy infantry are dead.

Action Drills on Contact
It is very important for the MG Fire Team to make effective use of smoke (Usually white). This can save them from being effectively engaged if they can obscure their position and movement. The general rule is after the smoke has been thrown the gunner moves first, the ammunition bearer second and the team leader third.

The loader will pick up the GPMG if the gunner is killed or wounded and is unable to fire. The fire team leader will pick up the gun if the ammo man is killed or wounded.

MG Teams are most vulnerable when moving. When moving with the GPMG it is important to move from cover to cover as quickly (and preferably as quietly) as possible. If you are in an enemy AO it is recommended to run crouching (unless over a long distance) so if the fire team is engaged you are able to stop and return fire reasonably effectively and quickly. A MG Team should never move un-escorted in a known or suspected hostile environment. There should always be either a second MG team covering or infantry fire team support.

Small Arms Coaching
-Put your video resolution as high as it will go, then bump your 3d resolution to 200%. This will make the targets MUCH clearer and easier to see(don't forget to bump it back down once you're done or next time you play on a real map your game will have very bad graphical lag). Also make your object detail very high. With it on low you won't even be able to see the targets at 500m. With it on high it helps even more with the crispness of the targets.

-Bump your mouse sensitivity as low as you can stand it. I have mine as low as it will go in the game. This will help with involuntary hand jerking while trying to hold your mouse steady.

-Bind another button to fire. As with real guns, if you click your mouse too hard and move it slightly you can throw your shot off. I personally use the numpad + to zoom in, * to fire, and I still use RMB to hold my breath.

-Hold your breath for at least one second before each shot. Aim at the target, hold your breath, adjust your aim, and fire. Then release your breath for a count of around 3 and line your shot up again, hold your breath, adjust aim, and fire again.

-Bullet Trajectory: The 5.56mm fires in an arc that apexes at ~175-200m. At 300m your shot should be dead on. At 200m your shot should technically be high, but in ArmA it seems to be low. At 500m you want to aim about a head to half a body height above your target. The 500m line is VERY tricky. You have to check wind direction at this range with shift-k, but that doesn't seem to make much of a difference. You can adjust for wind direction and hit the center of your target, and sometimes you can simply aim straight and ignore wind direction and still hit the center of the target. You can aim perfectly and your shots will still not hit, or hit the target next to the one you were aiming at. You WILL miss a lot at 500m. Don't get frustrated just aim properly and follow through properly. If you did well on all the other stages you should still be able to qualify expert with 4-5 out of 10 hits at 500m. Sometimes you'll hit 7-9, sometimes you'll only hit 3. It's left to the whims of the rifle gods, but knowing the basics and following them will maximize your potential to score hits at 500m.