Right here is the history bit
The M4 Sherman, officially Medium Tank, M4, was the most numerous battle tank used by the United States and some of the other Western Allies in World War II. The M4 Sherman proved to be reliable, relatively cheap to produce and available in great numbers. Thousands were distributed through the Lend-Lease program to the British Commonwealth and Soviet Union. The tank was named by the British for the American Civil War General William Tecumseh Sherman.
The M4 Sherman evolved from the interim M3 Medium Tank, which had its main armament in a side sponson mount. The M4 retained much of the previous mechanical design, but put the main 75 mm gun in a fully traversing turret. One feature, a one-axis gyrostabilizer, was not precise enough to allow firing when moving but did help keep the reticle on target, so that when the tank did stop to fire, the gun would be aimed in roughly the right direction. The designers stressed mechanical reliability, ease of production and maintenance, durability, standardization of parts and ammunition in a limited number of variants, and moderate size and weight. These factors, combined with the Sherman's then-superior armor and armament, outclassed German light and medium tanks of 1939–42. The M4 went on to be produced in large numbers. It spearheaded many offensives by the Western Allies after 1942.
When the M4 tank went into combat in North Africa with the British Army at El Alamein in the autumn of 1942, it increased the advantage of Allied armor over German armor and was superior to the lighter German long-barrel 50 mm-gunned Panzer III and the short-barrel 75 mm-gunned Panzer IV then in service. For this reason, the US Army believed that the M4 would be adequate to win the war, and no pressure was exerted for further tank development. Logistical and transport restrictions, such as limitations imposed by roads, ports, and bridges, also complicated the introduction of a more capable but heavier tank. Tank destroyer battalions using vehicles built on the M4 hull and chassis, but with open-topped turrets and more potent high-velocity guns, also entered widespread use in the Allied armies. Even by 1944, most M4 Shermans kept their dual purpose 75 mm M3. By 1944, the M4 was inferior to German heavy tanks, but was able to fight on with mutual support from numerical superiority and with support from growing numbers of fighter-bombers and artillery pieces.
The relative ease of production allowed huge numbers of the M4 to be manufactured, and significant investment in tank recovery and repair units allowed disabled vehicles to be repaired and returned to service. These factors combined to give the Allies numerical superiority in most battles, and many infantry divisions were provided with M4s and tank destroyers. A M4A3E8 variant was introduced, with improved suspension and a high-velocity 76 mm gun as used on the tank destroyers.
After World War II, the Sherman, often in updated versions, saw combat in many conflicts, including the Korean War, the Arab-Israeli Wars, and the Indo-Pakistani War of 1965.
Netherlands.
Type Medium tank
Place of origin United States
Service history
In service 1942–55 (U.S.)
1945–present (Other countries)
Used by United States, and many others (see Foreign variants and use)
Wars World War II, Chinese Civil War, Indonesian National Revolution, Greek Civil War, 1948 Arab–Israeli War, Korean War, Revolución Libertadora, Suez Crisis, Indo-Pakistani War of 1965, Six-Day War, Indo-Pakistani War of 1971, Yom Kippur War, Iran–Iraq War, 1958 Lebanon crisis, Lebanese Civil War, Cuban Revolution, Nicaraguan Revolution
Production history
Designer U.S. Army Ordnance Department
Designed 1940
Manufacturer American Locomotive Co., Baldwin Locomotive Works, Detroit Tank Arsenal, Federal Machine and Welder Co., Fisher Tank Arsenal, Ford Motor Company, Lima Locomotive Works, Pacific Car and Foundry Company, Pressed Steel Car Company, Pullman-Standard Car Company
Produced 1941–45
Number built 49,234 M4A3E8 model: 4542
Variants See U.S. variants and foreign variants
Specifications
Weight 66,800 pounds (30.3 tonnes; 29.8 long tons; 33.4 short tons)
Length 19 ft 2 in (5.84 m)
Width 8 ft 7 in (2.62 m)
Height 9 ft (2.74 m)
Crew 5 (commander, gunner, loader, driver, co-driver)
Armor 93 mm (3.7 in) effective against 7.5 cm APCBC with cast glacis
118 mm (4.6 in) effective against 7.5 cm APCBC with 47° RHA glacis
Main 75 mm M3 L/40 gun (90 rounds)
armament or
76 mm gun M1, M1A1C, or M1A2 (55 rounds)
M4A3E8 model: 76 mm M1A2
(71 rounds)
Secondary .50 cal Browning M2HB machine gun (300 rounds),
armament 2×.30-06 Browning M1919A4 machine guns (4,750 rounds)
Engine M4 and M4A1 model: Continental R975 C1 9 cylinder Radial engine,
400 hp (298 kW) at 2,400 rpm
M4A3 model: Ford GAA engine, DOHC 60º V-8 of 18 litres (1,100 cu.in.) displacement, 525 hp (392 kW)
M4A4 model:
Chrysler A57 multibank 30 cylinder 21-liter engine, 470 hp at 2,700 rpm.
Power/weight 13.5 hp (10.1 kW) / metric ton (early production, Chrysler A57)
15.7 hp (11.7 kW) / metric ton (late production, RD-1820)
Transmission Spicer manual, synchromesh, 4 forward (plus 1 overdrive) and 1 reverse gear
Suspension Vertical Volute Spring Suspension (VVSS) and Horizontal Volute Spring Suspension (HVSS) in other models
Fuel capacity 175 US gallons (660 litres)
Operational 120 miles (193 km) at 175 U.S. gal (660 L); 80 octane
range
Speed 25 to 30 mph (40 to 48 km/h)
U.S. design prototype
Cutaway Sherman showing transmission and driver's seat.
The U.S. Army Ordnance Department designed the Medium Tank M4 as a replacement for the Medium Tank M3. The M3 was an up-gunned development of the M2 Medium Tank of 1939, in turn derived from the M2 light tank of 1935. The M3 was developed as a stopgap measure until a new turret mounting a 75 mm gun could be devised. While it was a big improvement when tried by the British in Africa against early German tanks, the placement of a 37 mm gun turret on top gave it a very high profile, and the unusual side-sponson mounted main gun, with limited traverse, could not be aimed across the other side of the tank.
Detailed design characteristics for the M4 were submitted by the Ordnance Department on 31 August 1940, but development of a prototype was delayed while the final production designs of the M3 were finished and the M3 entered full-scale production. On 18 April 1941, the U.S. Armored Force Board chose the simplest of five designs. Known as the T6, the design was a modified M3 hull and chassis, carrying a newly designed turret mounting the M3's 75 mm gun. This became the Sherman.
The Sherman's reliability resulted from many features developed for U.S. light tanks during the 1930s, including vertical volute spring suspension, rubber-bushed tracks, and a rear-mounted radial engine with drive sprockets in front. The goals were to produce a fast, dependable medium tank able to support infantry, provide breakthrough striking capacity, and defeat any tank then in use by the Axis nations.
The T6 prototype was completed on 2 September 1941. The T6 upper hull was a single large casting. It featured a side hatch, and a single overhead hatch for the driver. In the later M4A1 production model, this large casting was maintained, although the side hatch was eliminated and a second overhead hatch was added for the bow gunner. The T6 was standardized as the M4 and production began in October.
Doctrine
A Sherman DD tank of 13th/18th Royal Hussars in action against German troops using crashed Horsa gliders as cover near Ranville, Normandy, 10 June 1944.
As the United States approached entry in World War II, armored employment was doctrinally governed by Field Manual 100–5, Operations (published May 1941, the month following selection of the M4 tank's final design). That field manual stated:
The armored division is organized primarily to perform missions that require great mobility and firepower. It is given decisive missions. It is capable of engaging in all forms of combat, but its primary role is in offensive operations against hostile rear areas.
The M4 was, therefore, not originally intended as an infantry support tank; in fact, FM 100-5 specifically stated the opposite. It placed tanks in the "striking echelon" of the armored division, and placed the infantry in the "support echelon". The field manual covering the use of the Sherman (FM 17–33, "The Tank Battalion, Light and Medium" of September 1942) devoted one page of text and four diagrams to tank-versus-tank action, out of 142 pages. This early armored doctrine was heavily influenced by the sweeping early war successes of German blitzkrieg tactics. By the time M4s reached combat in significant numbers, battlefield demands for infantry support and tank versus tank action far outnumbered the occasional opportunities of rear-echelon exploitation.
United States doctrine held that anti-tank work was primarily to be done by towed and self-propelled anti-tank guns, both of which were referred to as 'tank destroyers'.Speed was essential in order to bring the tank destroyers from the rear to destroy incoming tanks. This doctrine was rarely followed in combat, as it was found to be impractical. Commanders were reluctant to leave tank destroyers in reserve; if they were, it was also easier for an opposing armored force to achieve a breakthrough against an American tank battalion, which would not have all of its anti-tank weapons at the front during the beginning of any attack.
U.S. production history
M4A1 (76)W Sherman with cast hull
M4 and M4A1 (shown), the first Shermans, share the inverted U backplate and inherited their engine and exhaust system from the earlier M3 Medium Tank.
This M4A4 has extra armor plates in front of crew hatches.
The first production began with the Lima Locomotive Works on the assembly line set for tanks for British use. The first production Sherman was given over to the US Army for evaluation and it was the second tank of the British order that went to London. Named Michael probably after Michael Dewar, head of the British tank mission in the U.S., it was displayed in London and is now an exhibit at The Tank Museum, Bovington, UK.
In World War II, the U.S. Army ultimately fielded 16 armored divisions, along with 70 independent tank battalions, while the U.S. Marine Corps fielded six independent Sherman tank battalions. A third of all Army tank battalions, and all six Marine tank battalions, were deployed to the Pacific Theater of Operations (PTO). Prior to September 1942, President Franklin D. Roosevelt had announced a production program calling for 120,000 tanks for the Allied war effort, which would have created 61 armored divisions. Although the American industrial complex was not affected by enemy aerial bombing nor submarine warfare as was Japan, Germany and, to a lesser degree, Great Britain, an enormous amount of steel for tank production had been diverted to the construction of warships and other naval vessels. Steel used in naval construction amounted to the equivalent of approximately 67,000 tanks; and consequently only about 53,500 tanks were produced during 1942 and 1943.
The Army had seven main sub-designations for M4 variants during production: M4, M4A1, M4A2, M4A3, M4A4, M4A5, and M4A6. These designations did not necessarily indicate linear improvement. For example, A4 did not indicate it was better than an A3. These sub-types indicated standardized production variations, which were in fact often manufactured concurrently at different locations. The sub-types differed mainly in engines, although the M4A1 differed from the other variants by its fully cast upper hull, with a distinctive rounded appearance. The M4A4 had a longer engine system that required a longer hull and more track blocks, and thus the most distinguishing feature of the A4 was the wider longitudinal spacing between the bogies. M4A5 was an administrative placeholder designation for Canadian production. The M4A6 had a diesel engine and elongated chassis, but fewer than 100 of these were ever produced.
While most Shermans ran on gasoline, the M4A2 and M4A6 had diesel engines. The M4A2 was powered by a pair of GMC 6–71 two-stroke straight six engines, the M4A6 using a Caterpillar D-200 radial producing some 450 hp (340 kW) at 2,000 rpm, adapted from the "RD-1820" experimental diesel version of Wright Aeronautical's mass-produced Cyclone 9 aviation radial. These, plus the M4A4, which used the Chrysler A57 multibank engine, were mostly supplied to other Allied countries under Lend-Lease. "M4" can refer specifically to the initial sub-type with its Continental radial engine (R-975), or generically, to the entire family of seven Sherman sub-types, depending on context. Many details of production, shape, strength, and performance improved while in production, without a change to the tank's basic model number. These included more durable suspension units, safer "wet" (W) ammunition stowage, and stronger armor arrangements, such as the M4 Composite, which had a cast front hull section mated to a welded rear hull. British nomenclature differed from that employed by the U.S.
A 24-volt electrical system was used in the M4.
Designation Main Armament Hull Engine
M4 75 mm welded gasoline Continental R975 radial
M4(105) 105 mm howitzer welded gasoline Continental R975 radial
M4 Composite 75 mm cast front, welded sides gasoline Continental R975 radial
M4A1 75 mm cast gasoline Continental R975 radial
M4A1(76)W 76 mm cast gasoline Continental R975 radial
M4A2 75 mm welded GM 6046 diesel (conjoined 6-71s)
M4A3W 75 mm welded gasoline Ford GAA V8
M4A3E2 "Jumbo" 75 mm (some 76 mm) welded gasoline Ford GAA V8
M4A3E8(76)W "Easy Eight" 76 mm welded gasoline Ford GAA V8
M4A4 75 mm welded; lengthened gasoline Chrysler A57 multibank
M4A6 75 mm cast front, welded sides; lengthened diesel Caterpillar D200A radial
M4 Sherman: comparison of key production features of selected models
A 76 mm M1 gun-equipped Easy Eight Sherman
Early Shermans mounted a 75mm medium-velocity general-purpose gun. Although Ordnance began work on the Medium Tank T20 as a Sherman replacement, ultimately the Army decided to minimize production disruption by incorporating elements of other tank designs into the Sherman. Later M4A1, M4A2, and M4A3 models received the larger T23 turret with a high-velocity 76 mm M1 gun, which reduced the number of high-explosive and smoke rounds carried and increased the number of anti-tank rounds. Later, the M4 and M4A3 were factory-produced with a 105 mm howitzer and a distinctive mantlet, which surrounded the main gun, on the turret. The first standard-production 76 mm gun Sherman was an M4A1, accepted in January 1944, which first saw combat in July 1944 during Operation Cobra. The first standard-production 105 mm howitzer Sherman was an M4 accepted in February 1944.
In June–July 1944, the Army accepted a limited run of 254 M4A3E2 Jumbo Shermans, which had very thick hull armor and the 75 mm gun in a new, heavier T23-style turret, in order to assault fortifications. The M4A3 was the first to be factory-produced with the option of the horizontal volute spring suspension (HVSS) system, with wider tracks to distribute weight, and the smooth ride of the HVSS. Its experimental E8 designation led to the nickname "Easy Eight" for Shermans so equipped. Both the Americans and the British developed a wide array of special attachments for the Sherman, although few saw combat, remaining experimental. Those that saw action included the bulldozer blade for the Sherman dozer tanks, Duplex Drive for amphibious Sherman tanks, R3 flamethrower for Zippo flame tanks, and the T34 60-tube Calliope 4.5" rocket launcher mountable atop the Sherman's turret. The British variants (DDs and mine flails) formed part of the group of specialized vehicles collectively known as "Hobart's Funnies" (after Percy Hobart, commander of the 79th Armoured Division).
The M4 Sherman's basic chassis was used for all the sundry roles of a modern mechanized force: roughly 50,000 Sherman tanks, plus thousands more derivative vehicles under different model numbers. These included the M10 Wolverine and M36 tank destroyers; M7B1, M12, M40, and M43 self-propelled artillery; the M32 and M74 "tow truck"-style recovery tanks with winches, booms, and an 81 mm mortar for smoke screens; and the M34 (from M32B1) and M35 (from M10A1) artillery prime movers.
M4A4 Cutaway: 1 - Lifting ring, 2 - Ventilator, 3 - Turret hatch, 4 – Periscope, 5 – Turret hatch race, 6 – Turret seat, 7 – Gunner's seat, 8 – Turret seat, 9 – Turret, 10 – Air cleaner, 11 – Radiator filler cover, 12 – Air cleaner manifold, 13 – Power unit, 14 – Exhaust pipe, 15 – Track idler, 16 – Single water pump, 17 – Radiator, 18 – Generator, 19 – Rear propeller shaft, 20 – Turret basket, 21 – Slip ring, 22 – Front propeller shaft, 23 – Suspension bogie, 24 – Transmission, 25 – Main drive sprocket, 26 – Driver's seat, 27 – Machine gunner's seat, 28 – 75 mm gun, 29 – Drivers hatch, 30 – M1919A4 machine gun.
That's that bit out of the way appologies if it was too long
Part 1 of the build will be up soon
