M203 grenade launcher


The M203 is a single-shot 40 mm under-barrel grenade launcher designed to attach to a rifle. It uses the same rounds as the older stand-alone M79 break-action grenade launcher, which utilizes the high-low propulsion system to keep recoil forces low. While compatible with many weapons, the M203 was originally designed and produced by the United States military for the M16 rifle and its carbine variant, the M4. The launcher can also be mounted onto a C7, a Canadian version of the M16 rifle; this requires the prior removal of the bottom handguard.
Stand-alone variants of the M203 exist, as do versions designed specifically for many other rifles. The device attaches under the barrel, the launcher trigger being in the rear of the launcher, just forward of the rifle magazine. The rifle magazine functions as a hand grip when firing the M203. A separate, right-handed only, sighting system is added to rifles fitted with the M203, as the rifle's standard sights are not matched to the launcher. The version fitted to the Canadian C7 has a sight attached to the side of the launcher, either on the left or right depending on the user's needs.

History

The M203 was the only part of the United States Army's Special Purpose Individual Weapon project to go into production. The M203 has been in service since 1969 and was introduced to US military forces during the early 1970s, replacing the M79 grenade launcher and the conceptually similar Colt XM148 design. However, while the M79 was a stand-alone weapon, the M203 was designed as an under-barrel device attached to an existing rifle. Because the size and weight of 40 mm ammunition limits the quantities that can be carried, and because a grenade is often not an appropriate weapon for all engagements, an under-barrel system has the advantage of allowing its user to also carry a rifle, and to easily switch between the two.
A new grenade launcher, the M320, will eventually replace the M203 in the United States Army. The United States Marine Corps, Air Force, Coast Guard, and Navy continued to use the older M203, although the Marines began issuing the M320 in June 2017. The M320 features an advanced day/night sight, a double-action firing mechanism as well as other benefits, such as an unobstructed side-loading breech.

Uses

The M203 grenade launcher is intended to be used as close fire support against point and area targets. The round is designed to be effective at breaking through windows and exploding inside, blowing up doors, producing multiple casualties, destroying bunkers or emplacements, and damaging or disabling soft-skinned vehicles. In the Vietnam War, U.S. Navy and Coast Guard personnel on boats would lob 40 mm grenades into the water, to preemptively attack Viet Cong swimmers attempting to plant explosives on anchored or moored U.S. watercraft.
Its primary purpose is to engage enemies in dead space that cannot be reached by direct fire. A well-trained M203 gunner can use their weapon to suppress the enemy, based on movement and sight. In addition, the M203 can be used as a crowd control weapon when equipped with the M651 tactical CS grenade. While classified primarily as an anti-personnel weapon, the shaped charge featured in the HEDP round gives it the capability to penetrate lightly armored vehicles.

Rounds

The M203 is able to fire a variety of different rounds for many purposes. According to the U.S. Army Field Manual FM 3-22.31 40-MM Grenade Launcher, M203, there are eight different rounds for the M203:
  • high-explosive dual purpose round. The HEDP round has an olive drab aluminum skirt with a steel cup attached, white markings, and a gold ogive. It penetrates at least 5 cm when fired straight at steel armor at or less, or, at a point target, it arms between, causes casualties within a radius, and has a kill radius of 5 meters.
  • high-explosive round. The HE round has an olive drab aluminum skirt with a steel projectile attached, gold markings, and a yellow ogive. It arms between, produces a ground burst that causes casualties within a radius, and has a kill radius of.
  • star parachute round. This round is white impact or bar alloy aluminum, with black markings. It is used for illumination and signals and is lighter and more accurate than comparable handheld signal rounds. The parachute attached to the round deploys upon ejection to lower the candle at. The candle burns for about 40 seconds. A raised letter on the top of the round denotes the color of the parachute.
  • white star cluster round. This round is white impact or bar aluminum alloy, with black markings. The attached plastic ogive has five raised dots for night identification. The round is used for illumination or signals. It is lighter and more accurate than comparable handheld signal rounds. The individual stars burn for about 7 seconds during free fall.
  • ground marker round. This round is light green impact aluminum with black markings. It is used for aerial identification and for marking the location of soldiers on the ground. It arms between. If a fuse fails to function on impact, the output mixture provided in the front end of the delay casing backs up the impact feature. The color of the ogive indicates the color of the smoke.
  • practice round. Used for practice, this round is blue zinc or aluminum, with white markings. It produces a yellow or orange signature on impact, arms between, and has a danger radius of.
  • CS round. This round is gray aluminum with a green casing and black markings. Though it is a multipurpose round, it is most effective for riot control and in Urban Operations. It arms between and produces a white cloud of CS gas on impact.
  • buckshot round. This round is olive drab with black markings. Though it is a multipurpose round, it is most effective in thick vegetated areas or for room clearing. Inside, it has 20 metal pellets, each weighing, with a muzzle velocity of. The round has no mechanical-type fuse.

    Components

The M203 grenade launcher system comes with a variety of components, usually including the launcher, adapters for attachment to assault rifles, and leaf sights. M203s can also come with quadrant sights, mounting to an MIL-STD 1913 Rail, or to the carrying handle of an M16 rifle.
The U.S. Marine Corps also uses the SU-277/PSQ Grenade Launcher Sight, which features a holographic red dot for improved aiming, integrated ballistic data for automatic adjustment based on ammunition, infrared aiming laser, and a compact, lightweight design.

Variants

There are numerous variants of the M203 manufactured in the U.S., and throughout the world, for various applications. These vary chiefly in the length of the barrel, attachment type, and quick detach capability.
The standard M203 is intended for permanent attachment to the M16A1, M16A2 and M16A3 rifles, and utilizes a rifled barrel. The M203 unmodified to an A1/A2 series will not fit on the M4 carbine series.
The U.S. M203A1 has a barrel of 12 inches, while the SOPMOD M203A1 has a barrel. The M203A1 is intended for use with the M4 and M4A1 carbines, and uses a special bracket mount consisting of three screws and lacing wire. Only M203A2s consist of a quick release bracket.
The Canadian M203A1 by Diemaco is a similar design with a different mounting system that does not require mounting points of the same profile as the M16A1 rifle's. The weapon's barrel slides further forward than the standard American models, which allows longer rounds to be loaded. This model is identifiable by the increased distance between the grenade launcher's barrel axis and the rifle's.
The M203A2 is intended for use with the M4 series/M16A4 and now also authorized on the M16A2 rifle as the modular weapon system. Using standard barrels, the grenade launcher is intended for use in concert with the Knight's Armament Company M5 RAS. The M5 MWS rail system became authorized in December 2008 for the M16A2 Rifle. An advantage of this system is the use of range-finding optics to make precise targeting easier.
The M203PI system is used for attachment of the M203 to other rifles, including, but not limited to, the Steyr AUG, Heckler & Koch G3, and the MP5 sub-machine gun. Most of these other companies have since devised 40 mm grenade launchers custom integrated with the weapon.
The M203 DAX has a double-action trigger and longer breech opening to accommodate less-lethal rounds.
The M203 and M203A1 are currently manufactured by AIRTRONIC USA, Inc. of Elk Grove Village, Illinois for the U.S. Department of Defense under contract numbers W52H09-06-D-0200 and W52H09-06-D-0225. Each contract is for up to 12,000 units. Each unit is shipped with hand guard, leaf sight and quadrant range sight. The contracts unit prices vary from $840 to $1,050 each. The production rate is 1,500 units per month. The M203PI is manufactured for both the U.S. Department of Defense and for commercial sales to law enforcement agencies both in the United States and abroad, and for foreign military sales by of Miami, Florida.
The M203 37 mm version became available on the U.S. market in 2017. It is available in a and a barrel version. They are scroll marked: "Launcher, Grenade M203 40mm", even though they are actually 37 mm devices. These 37 mm versions are considered a "title 1 firearm", and are not classified as "destructive devices" under the NFA. These launchers can be sold the same as regular firearms on an ATF Form 4473.

Users