76 mm gun M1

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76 mm gun M1
M18 hellcat side.jpg
An M18 Hellcat armed with a 76 mm gun
Type Tank gun
Place of origin United States
Service history
Used by United States
Wars World War II
Specifications
Caliber 76 millimetres (3.0 in)

The 76 mm gun M1 was an American World War II-era tank gun, which replaced the 75 mm gun on late Medium tank M4s, and was used for all 76 mm Gun Motor Carriage M18 tank destroyers. The short-barreled, medium-velocity 75 mm M3 L/40 gun (which armed the standard M4 Sherman) was designed primarily as an infantry support weapon and fared poorly against the armor of German Panzer IV and StuG III tanks (with even worse performance against the Panther and Tiger), leading to calls for a higher velocity weapon.

The new 76mm gun represented a much needed increase in anti-tank performance, allowing the Sherman to easily engage the most common German armored vehicles like the Panzer IV and Stug III. When using HVAP (High Velocity Armor Piercing) rounds the M4 was able to engage the heavier Tiger I and Panther from normal combat ranges. Years later, during the Korean War, the 76mm Shermans were able to easily penetrate the Soviet T-34/85 tanks from typical combat ranges.

Design and development[edit]

It was a new gun with a breech similar to that of the 75 mm M3 Gun. It fired the same shell as the 3-inch (76 mm) gun of the 3in Gun Motor Carriage M10 tank destroyer, but from a different case. The 76 mm was developed as a lighter gun than the "3 inch". The gun received a muzzle brake and faster rifle twist during production.

While the 76 mm had less High Explosive (HE) and smoke performance than the 75 mm, the higher-velocity 76 mm gave better anti-tank performance, with firepower similar to many of the armored fighting vehicles it encountered, particularly the Panzer IV and StuG vehicles.

The M1 was tested on an M4 Sherman tank, it was then found that the long barrel caused balance problems. The barrel was shortened and a counterweight added to the breech to compensate giving the M1A1. The reduction in length - by about 15 inches - reduced performance but the 76 mm was still superior to the 75 mm gun.

When the counterweight was found to be insufficient, the turret design of the T23 tank was used on the M4 chassis to carry the 76mm gun.

Wholesale introduction of the 76 mm gun was opposed due to its inferior HE round - approx 0.9 lb of explosive to the 1.5 lb in the 75 mm round - and the muzzle blast which could create large dust clouds in dry conditions.[1] Later production guns were given a muzzle brake to deflect the blast sideways (M1A1C).

The UK was not interested in the 76 mm gun Sherman as they had their own guns and tanks under development - although of intermediate length between the M1 and M1A1 76 mm, their Ordnance QF 17 pounder (76.2 mm) anti-tank gun used about 5.5 lb (2.5 kg) more propellant. Developed as an expediency M4 Shermans converted to use the 17pdr were known as the Sherman Firefly.

Overall, the 76mm M1 was comparable to the 17pdr. Performance was roughly equal with the 17pdr enjoying better penetration qualities, while the 76mm weapon was more accurate.

Variants[edit]

  • M1 -57 calibre long gun[2]
  • M1A1 - 52 calibre long version of gun with breech counterweight.[3]
  • M1A1C - fitted with muzzle brake
  • M1A2 - fitted with muzzle brake

Usage[edit]

A T23 turret used on 76 mm gunned Shermans, here without the muzzle brake

With British Commonwealth designations in parentheses:

76 mm gunned Shermans supplied to the British were only used in Italy or by the Polish 1st Armoured Division in North-West Europe. The British supported their 75 mm gunned Shermans with QF 17 pdr (76mm) equipped "Fireflies"

Towed variant[edit]

From 1943, at the instigation of the head of the Armored Force General Jacob Devers, US Ordnance worked on a towed anti-tank gun based on the barrel of the M1, known as "76 mm gun T2 on carriage T3". Later interest in the project declined and in 1945 the program was officially canceled.[4]

Performance[edit]

Penetration of armor at 30 degrees from vertical at two ranges
Ammunition 500 m 1,000 m
Armour-Piercing Capped (APC), US M62 or Soviet APC 109 mm,[5] 93 mm[6] 92 mm[6]
Armour-Piercing Capped Ballistic Capped (APCBC)[7] 98–93 mm[8] 88 mm[8]
High-Velocity Armour-Piercing (HVAP)[8] 139 mm[7] 127 mm[7]
High-Velocity Armour-Piercing M93[6] 146 mm 127 mm
High-Velocity Armour-Piercing T-4[5] 147 mm 120 mm

See also[edit]

Weapons of comparable role, performance and era[edit]

Notes[edit]

  1. ^ M4 (76mm) Sherman Medium Tank 1943-65 p 7
  2. ^ Steven J. Zaloga, Jim Laurier M4 (76mm) Sherman Medium Tank 1943-65 p4
  3. ^ Steven J. Zaloga, Jim Laurier p4
  4. ^ Steven J. Zaloga, Brian Delf - US Anti-tank Artillery 1941-45, Osprey Publishing 2005 (New Vanguard 107), ISBN 1-84176-690-9, page 20.
  5. ^ a b Steven J. Zaloga. and Peter Sarson (1993). Sherman Medium Tank.
  6. ^ a b c R.P. Hunnicutt (1978). Sherman: A History of the American Medium Tank.
  7. ^ a b c Bovington Tank Museum (1975). Fire and Movement.
  8. ^ a b c Harry Woodman (1991). Tank Armament in World War Two.

References[edit]

Further reading[edit]

  • TM 9-308
  • SNL C-46
  • SNL C-58
  • SNL C-64

External links[edit]