M67 recoilless rifle
Encyclopedia
The M67 recoilless rifle was a 90-mm antitank recoilless rifle
made in the United States
and later in the Republic of Korea. It could also be employed in an antipersonnel role with the use of the M590 antipersonnel round. It was designed to be fired primarily from the ground using the bipod and monopod, but it could also be fired from the shoulder using the folded bipod as a shoulder rest and the monopod as a front grip. The weapon was air-cooled and breech-loaded, and fired fixed ammunition. It is a direct fire weapon, and sighting equipment for this purpose was furnished with each weapon.
together with the much larger 106mm M40. The M67 proved a reliable and effective weapon, though it was primarily used against personnel and fortifications in combat, and saw little or no use against armor. While troops praised its effectiveness, the M67 came in for heavy criticism due to the weapon's weight and length as well as its backblast, which often precluded its use in offensive operations. Because of these disadvantages, some Marine Corps units continued to use the old M20 rocket launcher (Super Bazooka) in preference to the M67. It was largely replaced in Army service by the TOW missile
system in 1970 and the M47 Dragon
anti-tank missile system in 1975.
The M67 was not completely withdrawn from infantry service. Instead, it was retained as a substitute standard antitank weapon for special tasks or battle environments. Since the batteries of the Dragon and the wires of the TOW would fail due to extremely low temperatures, the M67 was used for units deploying to arctic environments. As of 1988, the 6th Light Infantry Division in Alaska
was still using the M67 in its special weapons platoons. Similarly, the urban environment of West Berlin
prompted the Army to keep the weapon with the Berlin Brigade
as late as the mid-1980s. The Army Rangers also retained the M67 in its weapons platoons until it was replaced by the 84mm M3 Carl Gustav
in the 1990s.
In February 2011, it was reported that stocks of surplus M67 recoilless rifles were reintroduced by the 101st Airborne Division for limited combat service in Afghanistan. Numbers of these weapons were issued to the 4th BCT, 101st Airborne for use against fortifications, and concentrations of enemy personnel. The M67 was issued in response to a demand for a reloadable shoulder-fired weapon to be used in static defensive positions as well as ambushes. In particular, the flechette antipersonnel round is seeing common usage.
It was capable of maintaining a sustained fire rate of 1 round per minute, but the weapon could also be rapid fired at an increased rate of 1 round every 6 seconds (10 rpm) by a well trained crew. The rapid firing was limited to 5 rounds, with a mandatory 15 minute cool-off period afterward.
The M49A1 sub-caliber device, which uses NATO 7.62-mm rounds, is typically used for zeroing the sight and for qualifying purposes. The sight would be visually zeroed by setting crossed strings over the gun barrel opening (there was a rubber loop and notches at the end of the barrel to facilitate holding the string in the correct position), then looking through the barrel of the sub-caliber device (and crossed strings) and setting the fixed stadia, reticle sight to the same target. The sub-caliber rounds could then be used to further refine the zero and to qualify.
principle to defeat armor. It does not depend upon velocity at the moment of impact for its effect. It relies upon a concentration of the effect of the explosive filler through its shape. The conical shape of the filler concentrates the force of the explosion into a hot jet that blows its way through the armor. The shape of the filler is maintained by a metal cone which forms a slug when the filler is exploded. This slug or metal may or may not follow the explosive jet through the armor. The end of the projectile is a long and narrow stand-off of a length that allows the HEAT
jet to achieve maximum effect against the target.
The HEAT round is used primarily against armor. It can also be used against secondary targets such as gun emplacements and pillboxes with excellent results. It is capable of penetrating 3.5 ft (1.1 m) of packed soil
, 2.5 ft (0.8 m) of reinforced concrete
, or 1.15 ft (0.35 m) of armor plate (steel
).
s. The sides are scored to facilitate splitting when the round is fired.
When the projectile leaves the muzzle, the pressure ruptures the canister along the score marks to release the flechettes which disperse in a cone angle of approximately 8 degrees.
Data is from Jane's Infantry Weapons 1984–85
Recoilless rifle
A recoilless rifle or recoilless gun is a lightweight weapon that fires a heavier projectile than would be practical to fire from a recoiling weapon of comparable size. Technically, only devices that use a rifled barrel are recoilless rifles. Smoothbore variants are recoilless guns...
made in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and later in the Republic of Korea. It could also be employed in an antipersonnel role with the use of the M590 antipersonnel round. It was designed to be fired primarily from the ground using the bipod and monopod, but it could also be fired from the shoulder using the folded bipod as a shoulder rest and the monopod as a front grip. The weapon was air-cooled and breech-loaded, and fired fixed ammunition. It is a direct fire weapon, and sighting equipment for this purpose was furnished with each weapon.
History and use
Introduced in the early 1960s in Army and Marine Corps service, the M67 was used in the Vietnam WarVietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
together with the much larger 106mm M40. The M67 proved a reliable and effective weapon, though it was primarily used against personnel and fortifications in combat, and saw little or no use against armor. While troops praised its effectiveness, the M67 came in for heavy criticism due to the weapon's weight and length as well as its backblast, which often precluded its use in offensive operations. Because of these disadvantages, some Marine Corps units continued to use the old M20 rocket launcher (Super Bazooka) in preference to the M67. It was largely replaced in Army service by the TOW missile
BGM-71 TOW
The BGM-71 TOW is an anti-tank missile. "BGM" is a weapon classification that stands for "Multiple Environment , Surface-Attack , Missile ". "TOW" is an acronym that stands for "Tube-launched, Optically-tracked, Wire command data link, guided missile"...
system in 1970 and the M47 Dragon
M47 Dragon
The M47 Dragon is an American shoulder-fired, man-portable anti-tank missile system. It has since been phased out in US service, in favor of the newer FGM-148 Javelin system.-Description:...
anti-tank missile system in 1975.
The M67 was not completely withdrawn from infantry service. Instead, it was retained as a substitute standard antitank weapon for special tasks or battle environments. Since the batteries of the Dragon and the wires of the TOW would fail due to extremely low temperatures, the M67 was used for units deploying to arctic environments. As of 1988, the 6th Light Infantry Division in Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
was still using the M67 in its special weapons platoons. Similarly, the urban environment of West Berlin
West Berlin
West Berlin was a political exclave that existed between 1949 and 1990. It comprised the western regions of Berlin, which were bordered by East Berlin and parts of East Germany. West Berlin consisted of the American, British, and French occupation sectors, which had been established in 1945...
prompted the Army to keep the weapon with the Berlin Brigade
Berlin Brigade
After the end of World War II, under the conditions of the Yalta and Potsdam agreements, Allied forces occupied West Berlin. This occupation lasted throughout the Cold War...
as late as the mid-1980s. The Army Rangers also retained the M67 in its weapons platoons until it was replaced by the 84mm M3 Carl Gustav
Carl Gustav recoilless rifle
The Carl Gustav is the common name for the 84 mm man-portable reusable multi-role recoilless rifle produced by Saab Bofors Dynamics in Sweden...
in the 1990s.
In February 2011, it was reported that stocks of surplus M67 recoilless rifles were reintroduced by the 101st Airborne Division for limited combat service in Afghanistan. Numbers of these weapons were issued to the 4th BCT, 101st Airborne for use against fortifications, and concentrations of enemy personnel. The M67 was issued in response to a demand for a reloadable shoulder-fired weapon to be used in static defensive positions as well as ambushes. In particular, the flechette antipersonnel round is seeing common usage.
Description
The M67 is shaped like a long tube with the sight assembly and trigger offset to the side in opposite directions about half way along the barrel. Under this point is the monopod, with the bipod halfway back from there. The weapon required a crew of three to operate it; a gunner, assistant gunner (loader) and ammo bearer. The breech is hinged on the right side, and had to be swung open to load the round. It was then swung closed and when the rifle was fired, the rear end of the shell case broke up and was blown out of the back of the breech block. On the left side of the barrel, near the sight and trigger assemblies, was an asbestos heat shield to protect the gunner's shoulder and neck from the heat of the barrel when firing.It was capable of maintaining a sustained fire rate of 1 round per minute, but the weapon could also be rapid fired at an increased rate of 1 round every 6 seconds (10 rpm) by a well trained crew. The rapid firing was limited to 5 rounds, with a mandatory 15 minute cool-off period afterward.
The M49A1 sub-caliber device, which uses NATO 7.62-mm rounds, is typically used for zeroing the sight and for qualifying purposes. The sight would be visually zeroed by setting crossed strings over the gun barrel opening (there was a rubber loop and notches at the end of the barrel to facilitate holding the string in the correct position), then looking through the barrel of the sub-caliber device (and crossed strings) and setting the fixed stadia, reticle sight to the same target. The sub-caliber rounds could then be used to further refine the zero and to qualify.
Ammunition
Ammunition for the 90 mm rifle was issued in complete fixed cartridges. The term "fixed" means that the projectile and the cartridge case are crimped together. This ensures correct alignment of the projectile and the cartridge case. It also permits faster loading because the projectile and the cartridge case are loaded as one unit. The rear end of the cartridge case is made of frangible material that is completely destroyed when fired. The projectiles used are pre-engraved with a rifling band, that is, the rotating bands are cut to engage the rifled bore both to trap gases and to spin-stabilize the projectile.M371 practice round
The M371 is a practice round for the M371A1 HEAT round. It has the high explosive filler replaced with inert ballast to keep it at the same weight and flight properties. The nose cap contains a smoke pellet to mark the point of impact.- Cartridge weight: 9.25 lb (4.2 kg)
- Cartridge length: 28.10 in (714 mm)
- Projectile weight: 6.75 lb (3.06 kg)
- Muzzle velocity: 700 ft/s (213 m/s)
- Maximum effective range: 437 yd (400 m)
- Fuse: PIBD M530A1
M371A1 HEAT round
The M371A1 round utilizes a special fin-stabilized projectile which employs the shaped chargeShaped charge
A shaped charge is an explosive charge shaped to focus the effect of the explosive's energy. Various types are used to cut and form metal, to initiate nuclear weapons, to penetrate armor, and in the oil and gas industry...
principle to defeat armor. It does not depend upon velocity at the moment of impact for its effect. It relies upon a concentration of the effect of the explosive filler through its shape. The conical shape of the filler concentrates the force of the explosion into a hot jet that blows its way through the armor. The shape of the filler is maintained by a metal cone which forms a slug when the filler is exploded. This slug or metal may or may not follow the explosive jet through the armor. The end of the projectile is a long and narrow stand-off of a length that allows the HEAT
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
jet to achieve maximum effect against the target.
The HEAT round is used primarily against armor. It can also be used against secondary targets such as gun emplacements and pillboxes with excellent results. It is capable of penetrating 3.5 ft (1.1 m) of packed soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
, 2.5 ft (0.8 m) of reinforced concrete
Reinforced concrete
Reinforced concrete is concrete in which reinforcement bars , reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension. It was invented by French gardener Joseph Monier in 1849 and patented in 1867. The term Ferro Concrete refers only to concrete that is...
, or 1.15 ft (0.35 m) of armor plate (steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
).
- Cartridge weight: 9.25 lb (4.2 kg)
- Cartridge length: 28.10 in (714 mm)
- Projectile weight: 6.75 lb (3.06 kg)
- Muzzle velocity: 700 ft/s (213 m/s)
- Maximum effective range: 437 yd (400 m)
- Fuse: PIBD M530A1
M590 Antipersonnel Canister
The Antipersonnel (Canister) Cartridge M590 (XM590E1) or M590 cartridge is a flechette round designed for close-in defense against massed attacks on personnel positions. The cartridge consists of an aluminum cartridge case crimped to an aluminum canister. The canister consists of a thin-walled, deep-drawn, scored aluminum body which contains a payload of 2400 eight-grain (0.5 g), low-drag, fin-stabilized, steel-wire flechetteFlechette
A flechette is a pointed steel projectile, with a vaned tail for stable flight. The name comes from French , "little arrow" or "dart", and sometimes retains the acute accent in English: fléchette.-Bulk and artillery use:...
s. The sides are scored to facilitate splitting when the round is fired.
When the projectile leaves the muzzle, the pressure ruptures the canister along the score marks to release the flechettes which disperse in a cone angle of approximately 8 degrees.
- Cartridge weight: 6.79 lb (3.08 kg)
- Cartridge length: 19.19 in (487 mm)
- Projectile weight: 3.97 lb (1.8 kg)
- Muzzle velocity: 1,250 ft/s (381 m/s)
- Maximum effective range: 328 yd (300 m)
- Fuse: none
Performance relative to comparable weapons
| Weapon | Diameter | Muzzle Velocity | Warhead | Armor penetration (est.) | Effective Range | Sight |
|---|---|---|---|---|---|---|
 M67 |
90 mm | 213 mps | 3.06 kg HEAT | 350 mm | 400 m | 3X |
 M2 Carl GustafCarl Gustav recoilless rifle The Carl Gustav is the common name for the 84 mm man-portable reusable multi-role recoilless rifle produced by Saab Bofors Dynamics in Sweden... |
84 mm | 310 mps | 1.70 kg HEAT | 400 mm | 450 m | 2X |
 LRAC F1LRAC F1 The LRAC F1, officially called Lance-Roquettes AntiChar de 89 mm modèle F1 is a French reusable rocket launcher developed by Luchaire Defense SA, and manufactured in cooperation with Manufacture Nationale d'Armes de Saint-Étienne and was in the 1970s marketed by Hotchkiss-Brandt... |
89 mm | 300 mps | 2.20 kg HEAT | 400 mm | 600 m | N/A |
 RPG-7RPG-7 The RPG-7 is a widely-produced, portable, unguided, shoulder-launched, anti-tank rocket-propelled grenade launcher. Originally the RPG-7 and its predecessor, the RPG-2, were designed by the Soviet Union, and now manufactured by the Bazalt company... |
85 mm | 300 mps | 2.25 kg HEAT | 320 mm | 500 m | 2.5X |
 B-300B-300 The B-300 is a reuseable man-portable anti-tank weapon system developed by Israeli Military Industries in the late 1970s for use by the Israel Defence Force. The B-300 can be carried and operated by a single operator and is effective to approximately 400 meters... |
82 mm | 280 mps | 3.00 kg HEAT | 400 mm | 400 m | N/A |
Data is from Jane's Infantry Weapons 1984–85