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The M-16 Assault Rifle is an Assault Rifle originally developed by Colt in the United States based on the Armalite AR-15. Its early testing was tough and rigorous, and it was not liked by many in the top

branches of the American Military. However, through trial and error, it became one of the most Iconic assault rifles in the world.


The M16 Assault Rifle is the standard issue shoulder weapon in the US military. It marks a departure from normal ballistics in that it uses a smaller, high-velocity round (5.56mm caliber vs. 7.62mm). This results in a smaller and lighter weapon as well as smaller ammunition, significantly decreasing combat load.

The M16 was effective at ranges of less than 400–460 meters, the range within which United States experiences in World War II and Korea had indicated that small arms engagements would occur. The weapon permitted the heavily burdened soldier to maintain the same degree of firepower at a reduced weight. And finally, the M-16 allowed every soldier to have an automatic fire capability whenever the situation required it, while the weapon's lighter ammunition facilitated battlefield resupply in greater quantities, enabling the resupply of field units for longer periods of time.

While the M16 possessed less "stopping power" than the M14, it was more accurate due to the reduction in recoil stemming from the smaller projectile fired. Both the M16A1 and the AK-47 rifles were judged far more effective than the M14 in terms of expected casualties per combat load. In general, they produced two times

U.S. Marine training with his M16A2 rifle fitted with a M203 grenade launcher

the number of combat casualties that could be produced by the M14. Thus there was clear evidence of military utility in the M16 rifle, resulting in an increased degree of military advantage accruing to its user.

Rifle squads consist of a rifle squad leader and eight soldiers. The rifle squad leader is the senior tactical leader of the squad and controls the squad's movement and fires. He conducts squad training and maintains the squad's ability to conduct tactical missions successfully. Each infantry squad is further organized into two 4-man fire teams consisting of a team leader, a grenadier, and an automatic rifleman. The fourth member within each fire team is either the squad's antitank specialist or the squad's designated marksman. The fire team leader is a fighting leader and leads his team by example. The fire team leader controls the movement of his team and the placement of fires against enemy soldiers. He assists the squad leader as required. The infantry squad fights by fire teams and buddy teams.

Firepower is the capacity of a unit to deliver effective fires on a target. Firepower kills or suppresses the enemy in his positions, deceives the enemy, and supports maneuver. Without effective supporting fires the infantry cannot maneuver. Before attempting to maneuver, units must establish a base of fire. A base of fire is placed on an enemy force or position to reduce or eliminate the enemy's ability to interfere with friendly maneuver elements. Leaders must know how to control, mass, and combine fire with maneuver. They must identify the most critical targets quickly, direct fires onto them, and ensure that the volume of fires is sufficient to keep the enemy from returning fire effectively, and the unit from expending ammunition needlessly.

The M16A1/M16A2 rifle is the most common weapon fired in built-up areas. The M16A1/M16A2 rifle and the M249 are used to kill enemy personnel, to suppress enemy fire and observation, and to penetrate light cover. Leaders can use 5.56mm tracer fire to designate targets for other weapons. Close combat is the predominant characteristic of urban engagements. Riflemen must be able to hit small, fleeting targets from bunker apertures, windows, and loopholes. This requires pinpoint accuracy with weapons fired in the semiautomatic mode. Killing an enemy through an 8-inch loophole at a range of 50 meters is a challenge, but one that may be common in combat in built-up areas.

When fighting inside buildings, three-round bursts or rapid semiautomatic fire should be used. To suppress defenders while entering a room, a series of rapid three-round bursts should be fired at all identified targets and likely enemy positions. This is more effective than long bursts or spraying the room with automatic fire. Soldiers should fire from an underarm or shoulder position; not from the hip. When targets reveal themselves in buildings, the most effective engagement is the quick-fire technique with the weapon up and both eyes open. Accurate quick fire not only kills enemy soldiers but also gives the attacker fire superiority.

Within built-up areas, burning debris, reduced ambient light, strong shadow patterns of varying density, and smoke all limit the effect of night vision and sighting devices. The use of aiming stakes in the defense and of the pointing technique in the offense, both using three-round bursts, are night firing skills required of all infantrymen. The individual laser aiming light can sometimes be used effectively with night vision goggles. Any soldier using NVG should be teamed with at least one soldier not wearing them.

M16 3.jpg

The penetration that can be achieved with a 5.56-mm round depends on the range to the target and the type of material being fired against. The M16A2 and M249 achieve greater penetration than the older M16A1, but only at longer ranges. At close range, both weapons perform the same. Single 5.56-mm rounds are not effective against structural materials (as opposed to partitions) when fired at close range—the closer the range, the less the penetration.

For the 5.56-mm round, maximum penetration occurs at 200 meters. At ranges less than 25 meters, penetration is greatly reduced. At 10 meters, penetration by the M16 round is poor due to the tremendous stress placed on this high-speed round, which causes it to yaw upon striking a target. Stress causes the projectile to break up, and the resulting fragments are often too small to penetrate.

Even with reduced penetration at short ranges, interior walls made of thin wood paneling, sheetrock, or plaster

A soldier with an M4 carbine with a grenade launcher

are no protection against 5.56mm rounds. Common office furniture such as desks and chairs cannot stop these rounds, but a layer of books 18 to 24 inches thick can. Wooden frame buildings and single cinder block walls offer little protection from 5.56mm rounds. When clearing such structures, soldiers must ensure that friendly casualties do not result from rounds passing through walls, floors, or ceilings.

Armor-piercing rounds are slightly more effective than ball ammunition in penetrating urban targets at all ranges. They are more likely to ricochet than ball ammunition, especially when the target presents a high degree of obliquity.

The following common barriers in built-up areas stop a 5.56-mm round fired at less than 50 meters:*One thickness of sandbags.

  • A 2-inch concrete wall (unreinforced).
  • A 55-gallon drum filled with water or sand.
  • A small ammunition can filled with sand.
  • A cinder block filled with sand (block will probably shatter).
  • A plate glass windowpane at a 45-degree angle (glass fragments will be thrown behind the glass).
  • A brick veneer.
  • A car body (an M16A1/M16A2 rifle penetrates but normally will not exit).

Although most structural materials repel single 5.56-mm rounds, continued and concentrated firing can breach some typical urban structures. The best method for breaching a masonry wall is by firing short bursts (three to five rounds) in a U-shaped pattern. The distance from the gunner to the wall should be minimized for best results—ranges as close as 25 meters are relatively safe from ricochet. Ballistic eye protection, protective vest, and helmet should be worn.

Ball ammunition and armor-piercing rounds produce almost the same results, but armor-piercing rounds are more likely to fly back at the firer. The 5.56mm round can be used to create either a loophole (about 7 inches in diameter) or a breach hole (large enough for a man to enter). When used against reinforced concrete, the M16 rifle and M249 cannot cut the reinforcing bars.



The M16 was initially used by the U.S. Air Force in 1964. In 1965, the U.S. Army and U.S. Marine Corps began issuing a different version, the XM16E1, mostly to forces in Vietnam. In 1967, it was standardized as the primary assault rifle of the U.S. military as the M16A1. It had 3 fire modes: Safe, Semi, and Automatic Fire.


Entering service in the 1980s, the M16A2 was made to fire the NATO standard 5.56mm cartridge. The

A U.S. soldier with M16A2 at Schofield Barracks, Hawaii. The United States Army did not place a large order for the A2 model until 1986.

automatic fire mode of the M16A1 was replaced with a 3-round burst to avoid wasting ammunition. Other changes included an adjustable-windage rear sight, a case-deflector for left-handed shooters, a slightly longer stock, a heavier barrel, and cylindrical hand guards. The fire selector switch was also switched to the left side of the weapon. The "duckbill" flash suppressor was replaced with the "birdcage" version.


A fully-automatic version of the M16A2, issued solely by the U.S. Navy for use by SEALs and Seabees. The M16A3 is NOT a flat-top version of the M16A2, as is popularly believed. This confusion stems from Colt's use of the A2 and A3 designations for fixed sight and flat-top upper receivers respectively.


Retains the M16A2's semi-automatic fire, the carrying handle with the iron sights is now removable to all the attachment of dot sights and scopes. The handguards are also replaced with a Knight's Armament M5 Rail Adaptor System for attachment of lights, forward hand grips, laser sights, and other devices.


The Colt M16 LSW is an adaptation of the M16 for the squad support weapon role.

M4 carbine

Mechanically the same as the M16A4, the M-4 carbine has a shorter barrel and a collapsible buttstock, allowing better maneuvering in tight spaces such as room-clearing.

M4A1 Carbine

An M4 carbine with a fully automatic fire mode in place of 3-round burst for use by Special Operations troops.


  • Afghanistan
  • Australia (M16A1) (Replaced 1989 by Steyr AUG)
  • Bangladesh: (Used by Bangladesh military

    Brazilian marines using the M16A4

    , Special Forces and Counter Terrorism Units)
  • Barbados
  • Belize
  • Bolivia
  • Bosnia: from 2010 Armed Forces of Bosnia and Herzegovina will scrap the A1 versions, and use A2 and A4 versions. Standard issue rifle of Bosnian and Herzegovina military and delivered from USA's Colt Arsenal in Hartford.
  • Brazil
  • Brunei
  • Cambodia (M16A1)
  • Cameroon
  • Canada: C7 variant made by Colt Canada is used by the Canadian Forces.
  • Chile
  • Costa Rica
  • Democratic Republic of the Congo
  • Denmark
  • Dominican Republic
  • East Timor
  • Ecuador
  • El Salvador
  • Estonia
  • Eritrea
  • Fiji Cl

    Close-up detail view of the magazine, ejection port and carrying handle of a Colt M16A2 rifle

  • France
  • Gabon
  • Ghana
  • Greece
  • Grenada
  • Guatemala
  • Haiti
  • Honduras
  • India
  • Indonesia
  • Iraq: Iraqi army.
  • Israel
  • Jamaica
  • Jordan
  • Lebanon
  • Lesotho
  • Liberia
  • Lithuania: Lithuanian Armed Forces.
  • Malaysia
  • Mexico
  • Monaco
  • Morocco
  • New Zealand (Replaced 1988 by [[Stey

    Canadian soldier with a Diemaco C8 (M16 variant) fitted with red dot and a grenade launcher

    r AUG]])
  • Nepal
  • Netherlands: C7 variant is used by the Royal Netherlands Army.
  • Nicaragua
  • Nigeria
  • Oman
  • Pakistan: Special Service Group (SSG) of the Pakistan Army.
  • Panama (M16A1)
  • Peru
  • Philippines: Manufactured under license by Elisco Tool and Manufacturing.
  • Qatar
  • Senegal
  • Singapore: Local variant of the M16A1 (M16S1) manufactured under license by ST Kinetics.
  • Somalia
  • South Africa
  • South Korea: During Vietnam War, United States provided 27,000 M16 rifles to Republic of Korea Armed Forces in Vietnam. Also, 600,000 Units were manufactured under license by Daewoo. The delivery started in 1974 and ended in 1985.
  • Sri Lanka
  • Thailand (M16A1/A2/A4)
  • Tunisia
  • Turkey (M16A1/A2/A4)
  • Uganda
  • United Arab Emirates
  • United Kingdom: Special Air Service.
  • United States
  • Uruguay
  • Vietnam: M16A1, taken from South Vietnam

See also

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