The M203 is a 40 mm under rifle grenade launcher that was designed for use byt the United States Military with the M-16 Combat Rifle. The M203 was designed and procured as the replacement for the M79 grenade launcher of the Vietnam Era. The Grenade Launcher is manufactured by at least Colt, Bushmaster, and Knight Manufacturing in the United States and is also manufactured ouside the United States.

The launcher is also usable on several other rifles including the Steyr Aug and FN FAL.

The single shot launcher is designed to be lightweight and compact. It is breach loaded and is pump action. The launcher consists of a hand guard and 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 is capable of firing a variety of low velocity 40mm ammunition including High Explosive, Flare, and a variety of Non Lethal Rounds. The launcher also has a quadrant sight which may be attached to the M16 carrying handle and is used when precision is required out to the maximum effective range of the weapon.

In most cases, the grenade does not arm until it is 30 meters its launch.

There is a civilain version that is 37 mm and is popular in Law Enforcement. Most States do not allow the purchase of live grenades but practice rounds and flare rounds may be purchased.

Weight:	Launcher: 3 pounds (1.36 kilograms) - Empty, Rifle (M16A2): 8.79 pounds (3.99 kg) - Empty.
Caliber:	40 mm
Barrel Length:	12 inches (30.5 cm) Grenade Launcher Only.
Overall Length:	15 inches (38.1 cm) Grenade Launcher Only.
Action:	Pump Action.
Mode of Fire:	Single shot only
Payload:	Single Shot.
Effective Range:	Area Target: 1148.35 feet (350 meters), Point target: 492.15 feet (150 meters.)
Maximum Range:	1312.4 feet (400 meters)
Minimum Safe Range:	101.71 feet (31 meters)
Cost:	$4000
Made in:	United States
Special:	Lightweight. Mounts underneither the barrel of a Rifle.

By Mischa