.gif)
75 mm Gun (US)
Encyclopedia
The US 75 mm gun tank gun M2 and the later M3 were the standard American tank guns of the Second World War.
Besides use on the two main American medium tank
s of the war the M3 Lee
(M2 or M3 gun) and the M4 Sherman
(M3 gun). The lightweight M6 and M5 variants were developed to equip the Light Tank M24
and the B-25 Mitchell
bomber.
units were to be called in.
field gun of World War I fame which was also adopted by the United States and used well into World War II as the 75mm M1897 field gun. Both the tank and field guns fired the same range of 75x350R ammunition. The primary round was the M48 High Explosive. This 6.76 kg (14.9 lb) round travelled at 625 m/s (2,050 ft/s) and contained 1.5 pounds of TNT filling and choice of Super Quick (SQ) or Delay (PD) with 0.05 or 0.15 seconds of delay fuse. SQ was the standard setting with PD used against structures, gun positions or lightly protected vehicles. The field gun origins of the ordnance and ammunition ensured that the M2/3/6 series HE round was highly effective for its caliber. The M48 was available in 2 versions, standard or supercharge which increased the propellent charge for greater muzzle velocity (1885 ft/s (574.5 m/s) vs. 1470 ft/s (448.1 m/s)) and range (2,300 yards greater).
Other important rounds fired by the 75mm tank guns were the T30 Canister shot
for use against troops in the open at short range. This was essentially a giant shotgun shell full of large numbers of steel balls. Canister was used primarily in the Pacific. There was also a White Phosphorus (WP or "Willy Pete") round which proved highly effective in the Bocage
fighting around Normandy. Finally there was the Armor-piercing for which 2 different rounds were provided.
The first armor-piercing round was the 18 lb (8.2 kg) M72 AP-T, a plain uncapped AP round whose performance dropped off as range increased. M72 was replaced by the 6.8 kg (15 lb) M61 and later the improved M61A1 APC Shell. This was actually a APC-HE-T or Armor Piercing Capped High Explosive Tracer
type round which contained a tracer element so the gunner could follow the trajectory of the round to make corrections for the next shot if necessary. The cap improved ballistic performance and penetration. Once the projectile had penetrated the target a small explosive charge would detonate to increase damage inside the enemy vehicle. In practice the majority of M61 rounds were shipped without the explosive filler. M61 had a muzzle velocity of 620 m/s (2,030 ft/s) and was credited with the ability to penetrate 3.7 inches (94 mm) of armor plate at 500 yards range, which was a quite acceptable performance by the standards of 1942.
By July 1944 complaints started to pour in about the inadequate anti-tank performance of the M4 Medium tanks fitted with the 75mm M3 gun. During the breakout from Normandy American and British forces encountered the new generation of heavy German tanks and armored vehicles such as the Panther tank
, Tiger I
tank and Jagdpanzer IV
tank destroyer in quantity for the first time. These vehicles had thick frontal armor that proved largely immune to the M61 projectiles fired by the M3 tank gun and severely tarnished the reputation of the M4 Medium tank. The western allies countered by equipping increasing numbers of M4 Medium tanks with the 76 mm gun M1
for the American's and the Ordnance QF 17 pounder
for the British. These guns offered much improved performance against tanks but because they fired High Explosive rounds that were inferior to the 75mm guns, those guns never completely replaced the older models.
British tanks in the early years of World War II relied on high-velocity anti-tank guns such as the Ordnance QF 2 pounder
and Ordnance QF 6 pounder
for their primary armament. These guns had the great disadvantage for tank use of not having a truly effective High Explosive round or not even having the option of a HE round. The British after experiencing the effectiveness of the American 75mm tank guns in the infantry support role opted to adopt the American caliber and ammunition by the expedient of boring-out the 6 pounder tank gun to make the Ordnance QF 75 mm
. By 1944 this had become the standard British tank gun equipping the Cromwell tank
and Churchill tank
for the campaigns in northwest Europe.
A version used on the early Medium Tank M3
.
Longer derivative of the M2. Equipped American and British vehicles such as the Medium Tank M4
, the later models of the Medium Tank M3
and the Churchill III/IV
(scavenged from General Sherman tanks in the North African theatre). US Army also experimented with mounting of the M3 on various wheeled carriages for use as anti-tank gun, but the program was cancelled due to lack of requirement.
The 75-mm Aircraft gun M4 ia a modification of the M3 gun which is found in medium tanks. It differs from the M3 gun, only in having a seat for the spline machined in the tube. it was mounted on the M6 mount.
A lightweight version of the M3 with a lighter thin-walled barrel and a different recoil mechanism that was used in the B-25H Mitchell bomber
. Uses the same ammunition and has the same ballistics as the M3.
A version derived from the T13E1 for the Light Tank M24
.
Besides use on the two main American medium tank
Medium tank
Medium tank was a classification of tanks; the medium being intermediate in size and weight and armament between heavy tanks and light tanks.The medium tank concept has been eclipsed by the main battle tank.-History:...
s of the war the M3 Lee
M3 Lee
The Medium Tank M3 was an American tank used during World War II. In Britain the tank was called "General Lee", named after Confederate General Robert E. Lee, and the modified version built with a new turret was called the "General Grant", named after U.S. General Ulysses S. Grant.Design commenced...
(M2 or M3 gun) and the M4 Sherman
M4 Sherman
The M4 Sherman, formally Medium Tank, M4, was the primary tank used by the United States during World War II. Thousands were also distributed to the Allies, including the British Commonwealth and Soviet armies, via lend-lease...
(M3 gun). The lightweight M6 and M5 variants were developed to equip the Light Tank M24
M24 Chaffee
The Light Tank M24 was an American light tank used during World War II and in postwar conflicts including the Korean War and with the French in the War in Algeria and First Indochina War. In British service it was given the service name Chaffee, after the United States Army General Adna R...
and the B-25 Mitchell
B-25 Mitchell
The North American B-25 Mitchell was an American twin-engined medium bomber manufactured by North American Aviation. It was used by many Allied air forces, in every theater of World War II, as well as many other air forces after the war ended, and saw service across four decades.The B-25 was named...
bomber.
Development
U.S. armored doctrine in World War II saw the tank as a deep-attack or exploitation vehicle. The tanks job was to pour through a breach in the enemy front line created by infantry and artillery and exploit that breach by attacking the enemy rear. The tanks primary armament was seen as its machine guns and sheer bulk and crushing power. The main gun was seen as a means of overcoming obstacles as the tank proceeded to attack vital enemy rear areas. For this role the tank gun required good general-purpose performance but anti-tank capability was not paramount. The tank was not supposed to engage enemy tanks. If enemy tanks were encountered in numbers specialist Tank DestroyerTank destroyer
A tank destroyer is a type of armored fighting vehicle armed with a gun or missile launcher, and is designed specifically to engage enemy armored vehicles...
units were to be called in.
History
The 75mm tank gun has its origins in the famous French Canon de 75 modèle 1897Canon de 75 modèle 1897
The French 75mm field gun was a quick-firing field artillery piece adopted in March 1898. Its official French designation was: Matériel de 75mm Mle 1897. It was commonly known as the French 75, simply the 75 and Soixante-Quinze .The French 75 is widely regarded as the first modern artillery piece...
field gun of World War I fame which was also adopted by the United States and used well into World War II as the 75mm M1897 field gun. Both the tank and field guns fired the same range of 75x350R ammunition. The primary round was the M48 High Explosive. This 6.76 kg (14.9 lb) round travelled at 625 m/s (2,050 ft/s) and contained 1.5 pounds of TNT filling and choice of Super Quick (SQ) or Delay (PD) with 0.05 or 0.15 seconds of delay fuse. SQ was the standard setting with PD used against structures, gun positions or lightly protected vehicles. The field gun origins of the ordnance and ammunition ensured that the M2/3/6 series HE round was highly effective for its caliber. The M48 was available in 2 versions, standard or supercharge which increased the propellent charge for greater muzzle velocity (1885 ft/s (574.5 m/s) vs. 1470 ft/s (448.1 m/s)) and range (2,300 yards greater).
Other important rounds fired by the 75mm tank guns were the T30 Canister shot
Canister shot
Canister shot is a kind of anti-personnel ammunition used in cannons. It was similar to the naval grapeshot, but fired smaller and more numerous balls, which did not have to punch through the wooden hull of a ship...
for use against troops in the open at short range. This was essentially a giant shotgun shell full of large numbers of steel balls. Canister was used primarily in the Pacific. There was also a White Phosphorus (WP or "Willy Pete") round which proved highly effective in the Bocage
Bocage
Bocage is a Norman word which has entered both the French and English languages. It may refer to a small forest, a decorative element of leaves, a terrain of mixed woodland and pasture, or a type of rubble-work, comparable with the English use of 'rustic' in relation to garden...
fighting around Normandy. Finally there was the Armor-piercing for which 2 different rounds were provided.
The first armor-piercing round was the 18 lb (8.2 kg) M72 AP-T, a plain uncapped AP round whose performance dropped off as range increased. M72 was replaced by the 6.8 kg (15 lb) M61 and later the improved M61A1 APC Shell. This was actually a APC-HE-T or Armor Piercing Capped High Explosive Tracer
Tracer
Tracer may refer to:* Histochemical tracer, a substance used for tracing purposes in histochemistry, the study of the composition of cells and tissues...
type round which contained a tracer element so the gunner could follow the trajectory of the round to make corrections for the next shot if necessary. The cap improved ballistic performance and penetration. Once the projectile had penetrated the target a small explosive charge would detonate to increase damage inside the enemy vehicle. In practice the majority of M61 rounds were shipped without the explosive filler. M61 had a muzzle velocity of 620 m/s (2,030 ft/s) and was credited with the ability to penetrate 3.7 inches (94 mm) of armor plate at 500 yards range, which was a quite acceptable performance by the standards of 1942.
By July 1944 complaints started to pour in about the inadequate anti-tank performance of the M4 Medium tanks fitted with the 75mm M3 gun. During the breakout from Normandy American and British forces encountered the new generation of heavy German tanks and armored vehicles such as the Panther tank
Panther tank
Panther is the common name of a medium tank fielded by Nazi Germany in World War II that served from mid-1943 to the end of the European war in 1945. It was intended as a counter to the T-34, and to replace the Panzer III and Panzer IV; while never replacing the latter, it served alongside it as...
, Tiger I
Tiger I
Tiger I is the common name of a German heavy tank developed in 1942 and used in World War II. The final official German designation was Panzerkampfwagen Tiger Ausf. E, often shortened to Tiger. It was an answer to the unexpectedly formidable Soviet armour encountered in the initial months of...
tank and Jagdpanzer IV
Jagdpanzer IV
The Jagdpanzer IV, Sd.Kfz. 162, was a tank destroyer based on the Panzer IV chassis built in three main variants. As one of the casemate-style turretless Jagdpanzer designs, it was developed against the wishes of Heinz Guderian, the inspector general of the Panzertruppen, as a replacement for the...
tank destroyer in quantity for the first time. These vehicles had thick frontal armor that proved largely immune to the M61 projectiles fired by the M3 tank gun and severely tarnished the reputation of the M4 Medium tank. The western allies countered by equipping increasing numbers of M4 Medium tanks with the 76 mm gun M1
76 mm gun M1
The 76 mm Gun M1 was an American Forces 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 previous 75 mm M3 L/40 gun on the early M4 Sherman variants was designed more as an infantry support...
for the American's and the Ordnance QF 17 pounder
Ordnance QF 17 pounder
The Ordnance Quick-Firing 17 pounder was a 76.2 mm gun developed by the United Kingdom during World War II. It was used as an anti-tank gun on its own carriage, as well as equipping a number of British tanks. It was the most effective Allied anti-tank gun of the war...
for the British. These guns offered much improved performance against tanks but because they fired High Explosive rounds that were inferior to the 75mm guns, those guns never completely replaced the older models.
British tanks in the early years of World War II relied on high-velocity anti-tank guns such as the Ordnance QF 2 pounder
Ordnance QF 2 pounder
The Ordnance QF 2-pounder was a British anti-tank and vehicle-mounted gun, employed in the Second World War. It was actively used in the Battle of France, and during the North Africa campaign...
and Ordnance QF 6 pounder
Ordnance QF 6 pounder
The Ordnance Quick-Firing 6-pounder 7 cwt, or just 6 pounder, was a British 57 mm gun, their primary anti-tank gun during the middle of World War II, as well as the main armament for a number of armoured fighting vehicles...
for their primary armament. These guns had the great disadvantage for tank use of not having a truly effective High Explosive round or not even having the option of a HE round. The British after experiencing the effectiveness of the American 75mm tank guns in the infantry support role opted to adopt the American caliber and ammunition by the expedient of boring-out the 6 pounder tank gun to make the Ordnance QF 75 mm
Ordnance QF 75 mm
The Ordnance QF 75 mm, abbreviated to OQF 75 mm, was a British tank-gun of the Second World War. It was used instead of the Ordnance QF 6 pounder , an anti-tank gun, to give better performance against infantry targets in a similar fashion to the 75 mm gun fitted to the American...
. By 1944 this had become the standard British tank gun equipping the Cromwell tank
Cromwell tank
Tank, Cruiser, Mk VIII, Cromwell ,The designation as the eighth Cruiser tank design, its name given for ease of reference and its General Staff specification number respectively and the related Centaur tank, were one of the most successful series of cruiser tanks fielded by Britain in the Second...
and Churchill tank
Churchill tank
The Tank, Infantry, Mk IV was a heavy British infantry tank used in the Second World War, best known for its heavy armour, large longitudinal chassis with all-around tracks with multiple bogies, and its use as the basis of many specialist vehicles. It was one of the heaviest Allied tanks of the war...
for the campaigns in northwest Europe.
Variants
- M2
A version used on the early Medium Tank M3
M3 Lee
The Medium Tank M3 was an American tank used during World War II. In Britain the tank was called "General Lee", named after Confederate General Robert E. Lee, and the modified version built with a new turret was called the "General Grant", named after U.S. General Ulysses S. Grant.Design commenced...
.
- Barrel length: 31 calibresCaliberIn guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
- Muzzle velocity: 588 m/s (1,929 ft/s)
- Shell weight (M72 AP): 6.32 kg (14 lbs)
- Armour penetration (M72 AP shell, 457 m, at 90 degrees): 60 mm
- M3
Longer derivative of the M2. Equipped American and British vehicles such as the Medium Tank M4
M4 Sherman
The M4 Sherman, formally Medium Tank, M4, was the primary tank used by the United States during World War II. Thousands were also distributed to the Allies, including the British Commonwealth and Soviet armies, via lend-lease...
, the later models of the Medium Tank M3
M3 Lee
The Medium Tank M3 was an American tank used during World War II. In Britain the tank was called "General Lee", named after Confederate General Robert E. Lee, and the modified version built with a new turret was called the "General Grant", named after U.S. General Ulysses S. Grant.Design commenced...
and the Churchill III/IV
Churchill tank
The Tank, Infantry, Mk IV was a heavy British infantry tank used in the Second World War, best known for its heavy armour, large longitudinal chassis with all-around tracks with multiple bogies, and its use as the basis of many specialist vehicles. It was one of the heaviest Allied tanks of the war...
(scavenged from General Sherman tanks in the North African theatre). US Army also experimented with mounting of the M3 on various wheeled carriages for use as anti-tank gun, but the program was cancelled due to lack of requirement.
- Barrel length: 38.5 calibresCaliberIn guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
(3 m) - Muzzle velocity: 619 m/s (2,031 ft/s)
- Shell weight (M72 AP): 6.32 kg (14 lbs)
- Armour penetration (M72 AP shell, 457 m, at 90 degrees): 76 mm
- M4
The 75-mm Aircraft gun M4 ia a modification of the M3 gun which is found in medium tanks. It differs from the M3 gun, only in having a seat for the spline machined in the tube. it was mounted on the M6 mount.
- T13E1 / M5
A lightweight version of the M3 with a lighter thin-walled barrel and a different recoil mechanism that was used in the B-25H Mitchell bomber
B-25 Mitchell
The North American B-25 Mitchell was an American twin-engined medium bomber manufactured by North American Aviation. It was used by many Allied air forces, in every theater of World War II, as well as many other air forces after the war ended, and saw service across four decades.The B-25 was named...
. Uses the same ammunition and has the same ballistics as the M3.
- M6
A version derived from the T13E1 for the Light Tank M24
M24 Chaffee
The Light Tank M24 was an American light tank used during World War II and in postwar conflicts including the Korean War and with the French in the War in Algeria and First Indochina War. In British service it was given the service name Chaffee, after the United States Army General Adna R...
.
- Barrel length: L/38.5 calibresCaliberIn guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
(3 m) - Muzzle velocity: 619 m/s (2030 ft/s)
- Shell weight (M72 AP): 6.32 kg (14 lbs)
- Armour penetration (M72 AP shell, 457 m, at 90 degrees): 76 mm