As with other Grenade Launchers, the M203 is intended to bridge the gap between hand grenades and indirect fire assets. The M203 was designed and procured as the replacement for the M79 grenade launcher. Unlike the stand-alone M79, the M203 is mounted on the M16 rifle. The XM203 was type classified as the M203 in August 1969, gradually replacing the M79 Grenade Launcher during the early and mid-1970s.
Senior Airman Bryan Ables, 31st Security Forces Squadron, loads a 40mm blue practice round into an M203 grenade launcher, Cao Malinisio fire range, Italy, 11 Jan 2007.
1LT Matt Rivera, Combined Joint Task Force 76, aims his M203 40mm Grenade Launcher, Bagram Air Base firing range, Afghanistan, 16 Oct 2005.
A major drawback with the M79 Grenade Launcher was that the grenadier was armed only with a pistol in addition to the launcher, and thus diminished the firepower of the squad. The XM203 Grenade Launcher Attachment Development (GLAD) is a single-shot weapon designed for under-barrel use with the M16 series rifle. It fired its 40mm grenade, but also allowed the soldier to use his rifle when necessary.
The M203 consists of a hand guard and leaf sight assembly with an adjustable metallic, folding, short-range blade sight assembly, and an aluminum receiver assembly which houses the barrel latch, barrel stop and firing mechanism. The launcher also has a quadrant sight attachable to the M16A2 carrying handle, used when precision is required out to the maximum effective range of the weapon.
The M203A1 has a short barrel for airborne applications and a quick release mechanism to allow the user to tailor the weapon to individual missions. Like the M203, the M203A1 grenade launcher is also a single-shot weapon that fires the 40mm grenade, designed for use with the M4 Carbine. It is functionally identical to the M203.
Use of the M203 is limited by the need for a clear trajectory, its slow rate of fire and separate sights. The single-action M203 has to have the breech re-cycled to re-cock after a misfire. Targets must be far enough away to avoid risk of friendly casualties (at least 30 meters in combat).
The M203 sights were top-mounted on the rifle and have to be re-attached and re-zeroed each time the M203 is mounted. They often interfered with sights of the rifle itself.
M203 Grenade Launcher Ammunition
The M203 fires a range of low velocity 40mm cartridges. Examples include the High Explosive Dual Purpose (HEDP) 40mm rounds and an array of less-than-lethal munitions, including CN/CS/OC tear gas rounds, smoke, non-lethal projectiles, signal (eg Star Parachute) and practice rounds (blue upper case). See the Olive-Drab.com page on 40mm Grenade Cartridges for more information.
M203 40mm Grenade Launcher Characteristics
M203 40mm Grenade Launcher.
3 lbs empty (1.35kg); 3.6 lbs loaded (1.63kg)
Weight w/M16A2 loaded 30 rds
11.79 pounds (5.35 kg)
15 inches (38.1 cm)
12 inches (30.5 cm)
Max Effective Range, Area Target
Approximately 1150 feet (350 meters)
Max Effective Range, Point Target
Approximately 490 feet (150 meters)
The M203 Grenade Launcher is made by Colt Manufacturing at a unit cost of about $600. The technical manual is TM 9-1010-221-10 while FM 3-22.31 covers training and other aspects of the use of the M203 Grenade Launcher. Manuals are available from Amazon.com.
Find More Information on the Internet
There are many fine websites that have additional information on this
topic, too many to list here and too many to keep up with as they come and go.
Use this Google web search form to get an up to date report of what's out there.
For good results, try entering this: m203 grenade. Then click the Search button.