Military

M377 90-mm canister anti-personnel tank round

The 90 mm M377 canister anti-personnel round has a canister projectile filled with small flechettes for anti-personnel use at short ranges [some sources erroneously report this round as 105mm rather than 90mm]. It is stated to be particularly effective against personnel in dense foliage. Although the US Army was apparently the only armed force to employ this round and the guns used to fire it are no longer in US service, there is still the possibility that existing stocks of these rounds might be passed to other nations.

The 90 mm M377 canister cartridge is a fixed round, with a canister projectile crimped into a brass cartridge case. A single gilding-metal drive band encircles the canister base assembly. The canister projectile has a thin steel cylindrical body welded to a heavy steel cup-shaped base assembly. The blunt-nosed body has four equally spaced axial grooves extending from the forward edge of the canister body along about half its length. The body interior is filled with 5,600 flechettes, each weighing approximately 0.5 g, held in place by a crimped closing cup.

When the gun is fired, the canister body is propelled along the barrel. As it emerges from the gun muzzle, air pressure on the closing cup and the centrifugal forces acting on the body combine to cause the canister to break open along the four axial grooves. The flechettes are then free to disperse across a conical angle of 14º. The maximum effective range of the flechettes is approximately 400 m, at which range the arc is about 96 m wide. The 90 mm M377 canister round uses a brass M108B1 rimmed cartridge case with an M58 black-powder percussion primer press-fitted to the base. The propelling charge is 4.08 kg of M6 propellant.

The M4 General Sherman was the main battle tank designed and built by the United States for the conduct of World War II. The Sherman's low-velocity 75 or 76 mm gun was chosen because the Army's artillery branch wanted a cheap, reliable weapon for fire support. The T26E3 with the 90mm gun was adopted as the Army's standard tank in March 1945 under the designation of M26 Heavy Tank with the name 'Pershing' after the founder of the US Tank Corps in World War 1, General John J Pershing.

Named for Gen. George S. Patton, the M47 went into production in April, 1951. The main gun was the M36 90mm gun with an M12 optical rangefinder fitted. Developed from the M47 "General Patton" tank, the M48 was the mainstay of the US Army and Marines in Vietnam. Canister and HE were the primary main gun ammunition types used in Vietnam. Beehive was effective, but usually in short supply. WP was useful, but dangerous to carry since it ignited if split open by a mine or RPG strike, so crews tended to expend it as soon as possible. HEAT briefly was popular after NVA tanks were engaged at Bien Het, but HE was usually preferred against bunkers. Production on the M60 Patton began in 1960, and the M48 was withdrawn from American service in favor of the M60, a further development of the M48 carrying a 105mm gun. The M48 Patton ws the last platform to use the M377 90-mm canister anti-personnel tank round.