75 mm gun M2–M6
A number of 75 mm guns were fielded for service by the United States in World War II, in both the Army and the Marine Corps.
There were two lines, howitzers that could trace their design back to the First World War and a series of anti-tank guns that equipped the American tanks at the start of the Second.
Howitzer
The howitzers came from a need for a gun that could be moved across difficult country. The gun and carriage was designed so that it could be broken down into several pieces to be carried by mule or similar pack animal.
M1
Short barrel (16 calibres) pack howitzer gun.
- Rate of fire: 25 rounds per minute
- Muzzle velocity: 1,250 ft/s (380 m/s)
- Range: 9,610 yards (8790 m)
- Shell: 6.3 kg
M2
M1 howitzer gun converted for use on the Howitzer Motor Carriage M8, a Stuart tank conversion, and by use of the same turret on the LVT in Marine Corps
M3
A new build howitzer gun as used on the HMC M8.
M8
A specially modified pack howitzer (carriage and gun) designed to be airportable. Either parachuted in sections or, as with British practice, delivered whole to the battlefield by Horsa glider. It replaced the 3.75 inch howitzer in use with the British airborne units and was used at Arnhem during Operation Market Garden.
- Overall length: 12 ft 0 in (3.7 m)
- Width: 3 ft 11 in (1.2 m)
- Height: 2 ft 10 in (864 mm)
- Weight: 1339 lb (607 kg)
- Elevation: -5º to +45º
- Maximum range : 9,760 yd (8920 m)
- Rate of fire : 3 to 6 round/min
Tank gun
The United States designs for tanks chose a gun that could be used to support infantry rather than direct tank to tank action for which other specialist vehicles, the tank destroyers, were available. The American army fielded only two medium tanks in World War 2, the M3 and the M4, both of which used the 75 mm gun.
M2
A short gun used on pre-1941 tanks such as the M3 Lee or British Grant version. It was replaced by the M3.
- Barrel length: 31 calibres
- Muzzle velocity: 1,860 ft/s (570 m/s)
- Shell weight: 15 lb (7 kg)
- Armour penetration: up to 3 in (76 mm)
M3
Longer version of the M2. Equipped American and British vehicles such as the M4 Sherman, the later models of the M3 Grant and the Churchill IV (scavenged from M4 Sherman tanks).
- Barrel length: 40 calibres (3 m)
- Muzzle velocity: ~2,000 ft/s (610 m/s)
- Shell weight 15 lb (7 kg)
- Armour penetration ~3.5 in (89 mm) depending on AP shell
To gain the benefits of the 75 mm gun, particularly its HE shell, the British designed their OQF 75 mm to take the same rounds giving both their main tanks, the Sherman and Cromwell the same ammunition.
M6
A light version, derived from an aircraft gun, able to be fitted to a smaller tank such as the M24 Chaffee. Same ammunition and ballistics as M3.