Mk 18 Mod 0 grenade launcher

Mk 18 Mod 0 grenade launcher
Mk 18 Mod 0 grenade launchers (right and on tripod) at the War Remnants Museum in Ho Chi Minh City.
Type	Grenade launcher
Place of origin	United States
Service history
In service	1960s−1970s
Used by	United States Navy United States Army
Wars	Vietnam War
Production history
Designer	Honeywell Ordnance Division [1]
Manufacturer	Honeywell Ordnance Division
Produced	1965−1968
No. built	1,200 [2]
Specifications
Mass	17 lb (7.7 kg) [1]
Barrel  length	12 in (300 mm) [2]
Crew	2
Cartridge	40×46mm grenade
Caliber	40 mm (1.6 in)
Barrels	1
Action	Hand cranked, manual reloading
Rate of fire	250 rounds per minute [1] [2]
Muzzle velocity	215 ft/s (66 m/s) [3]
Effective firing range	330 yd (300 m) [3]
Feed system	Belt
Sights	Iron sights

The Mk 18 Mod 0 was a 40x46mm grenade launcher used by the United States Navy during the Vietnam War and also the last known hand crank operated firearm since the Gatling gun. It was replaced by the Mk 19 grenade launcher in service with the United States Armed Forces.

Design

This weapon is manually-operated and belt-fed. The use of a split breech mechanism allowed the weapon to be simple. The Mk 18 Mod 0 featured a pistol grip, iron sights, and a control knob with three different settings: Safe, Load, and Fire. The only hand-cranked weapon to enter US military service since the Gatling Gun, two rounds were loaded and fired for every complete rotation, while spent cases were reinserted into the belt. ^[2] The weapon was light, weighing only 17 pounds (7.7 kg), ^[1] and had an effective range of 330 yards (300 m). ^[3]

For watercraft 48-round ammunition boxes were issued while for ground operations a 24-round box was used. Belts had to be manually loaded by the crews before use and could be reused up to four or five times. ^[2]

Employment

About 1,200 launchers were produced primarily for the US Navy, while the US Army purchased 20 for testing. ^[2]

The Mark 18 was used primarily on small boats or in fixed positions such as bunkers. The US Army mounted some on M151A1 Jeeps for patrols; their primary users were the so-called "river rats" and the SEALs. They could be mounted on M2HB, M60, M1919 tripods, or pintle mounts, ^[2] but could not be fired without such a mount.^{[ citation needed ]}

Armored Troop Carrier (LCM)s of the Mobile Riverine Force usually mounted two Mk 18s. ^[4]

After the Vietnam War, the Mk 18 Mod 0 was replaced by the Mk 19 automatic grenade launcher. ^[2]

Gallery

A Mk 18 grenade launcher (upper) and Mk 19 (lower) displayed at Hanoi Weaponry Museum

A Patrol Craft Fast crewman loads a Mk 18 Mod 0

References

1. "Picture News". Popular Science. Vol. 191, no. 1. New York, NY: Bonnier Corporation. July 1967. p. 36. Retrieved 4 February 2025.
2. Rottman 2017, p. 44.
3. Friedman 1987, p. 441.
4. Sherwood, John (2015). War in the Shallows: U.S. Navy and Coastal and Riverine Warfare in Vietnam 1965-8. Naval History and Heritage Command. p. 176. ISBN   9780945274773. This article incorporates text from this source, which is in the public domain .

Bibliography

• Friedman, Norman (1987). U.S. Small Combatants, Including PT-boats, Subchasers, and the Brown-water Navy: An Illustrated Design History. Naval Institute Press. ISBN   978-0-87021-713-5 . Retrieved 4 February 2025.
• Rottman, Gordon L. (2017). US Grenade Launchers: M79, M203, and M320. Bloomsbury Publishing. ISBN   978-1-4728-1954-3.

External links

• Mk 18 Mod 0 at Securityarms
• www.quarry.nildram.co.uk
• www.warboats.org