M67 recoilless rifle

Adopted in 1959 in Army service, the M67 was used in the Vietnam War together with the much larger 106 mm M40. The M67 proved an effective weapon, though it was primarily used against personnel in combat, and saw little or no use against armor and even against fortifications. While troops praised its effectiveness, the M67 came under heavy criticism due to the weapon's weight and length as well as its backblast, which often precluded its use in offensive operations. The M67 was issued in lieu of the standard issue Carl Gustav for these armies. This may have been to simplify logistics, or it may be that ammunition for the Carl Gustav could not be sourced due to Swedish opposition to the war in Vietnam. The M67 was not completely withdrawn from infantry service. Royal Saudi Land Forces fielded M67s against Iraq during Gulf War. In February 2011, it was reported that stocks of surplus M67 recoilless rifles were reintroduced to the 101st Airborne Division for limited combat service in Afghanistan. Numbers of these weapons were issued to the 506th Infantry Regiment, "Currahee", 4th Brigade Combat Team, 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 anti-personnel round saw common usage. The M67s were eventually phased out again as the Army expanded issuing of the M3 Carl Gustav recoilless rifle to regular infantry units. == Production ==

It was designed by the Midwest Research Institute in Kansas City, Missouri. by Kia Motors, while rounds were manufactured by Poongsan Corporation. == Description ==

The M67 is shaped like a long tube with the sight assembly and trigger offset to the side in opposite directions about halfway along the barrel. Under this point is the monopod, with the bipod halfway back from there. The weapon requires a crew of three to operate it; a gunner, assistant gunner (loader) and ammunition bearer. The breech is hinged on the right side, and has to be swung open to load the round. It is then swung closed and when the rifle is fired, the rear end of the shell case breaks up and is blown out of the back of the breech block. On the left side of the barrel, near the sight and trigger assemblies, is an asbestos heat shield to protect the gunner's shoulder and neck from the heat of the barrel when firing. It is capable of maintaining a sustained fire rate of one round per minute, but the weapon could also be rapid fired at an increased rate of one round every six seconds (10 rpm) by a well trained crew. The rapid firing is limited to five 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 is visually zeroed by setting crossed strings over the gun barrel opening (a rubber loop and notches at the end of the barrel 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 can then be used to further refine the zero and to qualify. == Ammunition ==

Ammunition for the 90 mm rifle was issued in complete fixed cartridges. • 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 Anti-personnel Canister The Antipersonnel (Canister) Cartridge M590 (XM590E1) or M590 cartridge is a flechette round designed for close-in defense against massed infantry attacks. The cartridge consists of an aluminum cartridge case crimped to an aluminum canister. The canister consists of a thin-walled, deep-drawn, aluminum body that contains a payload of 2,400 eight-grain (0.5 g), low-drag, fin-stabilized, steel-wire flechettes. When the canister leaves the muzzle, the pressure ruptures the canister along inscribed 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 M591 Antipersonnel round The M591 is an HE round with a muzzle velocity of . == Performance relative to comparable weapons ==

Data is from Jane's Infantry Weapons 1984–85 == Users ==

with a M67 in 2015. Current • • • • • • • • • • • • == See also ==

• (JIW) Hogg, Ian. ''Jane's Infantry Weapons 1984–85'', London: Jane's Publishing Company Ltd., 1984. == External links ==