M40 recoilless rifle

M40 Recoilless Rifle
A deactivated M40 on display at the Philippine Army Museum
Type	Recoilless rifle
Place of origin	United States
Service history
In service	1955 – present
Used by	See Users
Wars	List of Conflicts Vietnam War Suez Crisis Algerian War[1] Portuguese Colonial War Cambodian Civil War Laotian Civil War Indo-Pakistani War of 1965[2] Six-Day War[3] Western Sahara War Angolan Civil War[4] Indo-Pakistani War of 1971 Bangladesh Liberation War[5] Rhodesian Bush War Nicaraguan Revolution Third Indochina War Soviet–Afghan War Iran–Iraq War Lebanese Civil War[6] Salvadoran Civil War[7] Chadian–Libyan conflict[8] Somali Civil War[9] 1989 Philippine coup d'état attempt Gulf War[10] War in Afghanistan[11] Libyan Civil War[12] Syrian Civil War[11] Iraqi Civil War (2014–2017)[13] Yemeni Civil War (2015–present)[14]
Production history
Manufacturer	Watervliet Arsenal
Specifications
Mass	209.5 kg (462 lb)
Length	3.404 m (11 ft 2 in)
Height	1.12 m (3 ft 8 in)
Shell	105×607mmR (HEAT, HEP, HEAP, Canister)
Caliber	105 mm (4.1 in)
Recoil	Recoilless
Carriage	Tripod
Elevation	−17° to +65° (between mount legs) −17° to +27° (over mount leg)[15]
Traverse	360°
Muzzle velocity	503 m/s (1,650 ft/s)[15] (M344 HEAT)
Effective firing range	1,350 m (1,480 yd)
Maximum firing range	6,870 m (M346A1 HEP-T)[16]

The M40 recoilless rifle^{[17][18][19][20]} is a portable, crew-served 105 mm recoilless rifle made in the United States. Intended primarily as an anti-tank weapon, it could also be employed in an antipersonnel role with the use of an antipersonnel-tracer flechette round. The bore was commonly described as being 106 mm caliber but is in fact 105 mm; the 106 mm designation was intended to prevent confusion with incompatible 105 mm ammunition from the failed M27.^[18] The air-cooled, breech-loaded, single-shot rifle fired fixed ammunition and was used primarily from a wheeled ground mount. It was designed for direct firing only, and sighting equipment for this purpose was furnished with each weapon, including an affixed spotting rifle.

A limited number of M50 Ontos were built as a self-propelled light armored tracked anti-tank vehicle. They had six 105 mm M40 recoilless rifles as its main armament, which could be fired in rapid succession against a single target to guarantee a kill.

Replacing the M27 recoilless rifle, the M40 primarily saw action during the Vietnam War and was widely used during various conflicts thereafter in Africa or in the Middle East. It was replaced by the BGM-71 TOW anti-tank missile system in the US Armed Forces.