M4 76 Firefly
Combat Mass: 30,3 mt
Armament: M2 L/32 or M3 L/40 75 mm (2.95 in) with 90 rounds, 2 Browning M2HB cal.30 M1919 (7.62 mm) machine-guns
Engine: Continental R975 9-cyl. air-cooled gasoline, 400 hp (298 kW)
Transmission: Clutch - Mechanical; Multi Plate; Dry Type Gearbox - Manual Synchromesh Type; 5 Fwd 1 Rev Controlled Differential Combining Steering and Brakes
Speed:48 km/h on road
Operating Range: Road 193km - Cross Country 110 km
Production of the M4
The first factory which delivered the M4 was the Lima Locomotive Works. All of these first batches were sent to the British Army through Lend-Lease, and fought in Africa. They found themselves instrumental in many operations which turned the tide of the war in this sector in favor of the Allies. At first, production rate was of 1000 M4s a month, but rose quickly as more factories were involved (11 total), to a figure of 2000 each month by mid-1942. These included (for all variants) Pressed Steel Cars Co., Pacific Car & Foundry, Baldwin Locomotive Works, American Locomotive Co., Pullman Car, Chrysler’s Detroit Tank Arsenal, Pullman Standard Car Manufacturing Co., Federal Welder, Fisher and Grand Blanc in Michigan, the last being specially built for the purpose during the war. A total of 6748 M4s (from July 1942 to January 1944) were produced, as well as 1641 of the late variant equipped with a 105 mm (4.13 in) howitzer for infantry support, the M4(105). Early models had the three-piece bolted nose, while later models had a mixed cast/rolled hull. The gun mantlet also evolved from the M34 to the more protective M34A.
This first major version was introduced early on in February 1942. It had a fully cast, rounded upper hull. Production of the regular M4A1 totaled 6281 machines until December 1943, but it was replaced by the M4A1(76)W, which received a more recent 76 mm (2.99 in) M1 main gun. 3396 of these improved models were built until March 1945. Performance of the regular “short” M2 75 mm (2.95 in) L/31 varied with the ammunition used, to a range from 259 m/s (850 ft/s) (smoke round) to 587 m/s (1926 ft/s) (APC M61), while the longer M3 L/40 allowed a 731 m/s (2400 ft/s) muzzle velocity. But the most efficient was the 1943 model 76 mm (2.99 in) M1 & M1A1 L/55, which had a 792 to 1036 m/s (2600 to 3400 ft/s) muzzle velocity with the HVAP ammo, being capable of piercing an 100 mm (3.94 in) steel plate at 450 m (1476 ft). Maximum range was 14 km (8.69 mi). Following a painful war experience, the ammo racks and fuel tanks were protected by watery jackets. The commander cupola was also new, featuring 6 prismatic vision blocks 76 mm (3 inches) thick with laminated bullet-proof glass. The engine was the modernized Continental R975-C1.
The M4A3 was first delivered by the Ford Motor Company in June 1942, alone delivering 1690 machines by September 1943. It was produced to a total of 5015 by all manufacturers combined. Early versions still had the dry ammunition stowage, direct vision slots for the driver and the 60 degree hull glacis (89 mm/3.5 in). The 3071 next had wet ammo stowage and a newer commander cupola. Most of all, it featured the new liquid-cooled Ford V8 500 hp engine, which was capable of giving a top speed of 42 km/h on road (26 mph), and a 209 km (130 mi) range. The suspension was the unchanged VVSS, but the transmission was now protected by a one-piece cast steel armored cover. Driver vision slots were augmented by bullet-proof glass and protective covers. Mid-production they also saw the adoption of duckbills, extended end connectors for the tracks, which improved the grip on soft terrains. Early series also saw extra 25 mm (1 in) thick applique armor welded over the ammo storage bins and the turret gunner position, later removed. By 1943-44, the recognition white stars were usually painted black or olive drab in order to mask them to enemy gunners, which used them as an aiming point. The 76 mm (3 in) version, the M4A3(76)W was first introduced in March 1944 and a total of 4500 were delivered until April 1945.
The M4 76 Firefly
The Sherman Firefly was in fact a British project, which started as soon as the highly successful British AT QF 17-pdr (76.2 mm/3 in) was chosen to equip the new generation of Cruiser tanks. Paradoxically, it had been rejected in 1943 by the Ministry of Supply’s Tank Decision Board, on the charges that the already planned Centurion and Comet would be sufficient. At the same time the Cromwell, fitted with a Vickers 75 mm (2.95 in) and the Challenger, with the 17-pdr (76.2 mm/3 in), just entered intensive tests before production.
The Firefly was the brainchild of veteran tank commander Lt. Col. George Witheridge and Major George Brighty, working at Lulworth on the A30 Challenger project. They militated for the project despite official opposition and the final prototype was given roots thanks to the work of W.G.K. Kilbourn, an engineer from Vickers, which succeeded in adapting the turret to its new purpose. As the A30 project suffered further delays, after the final tests in February 1944, a 2100 order for the modified Sherman was given the highest priority by Winston Churchill himself. The “Firefly”, also officially called Sherman VC or IC, was produced until the end of the war in Europe, in May 1945, from Lend-Lease shipped hulls and turrets, based on M4A4, M4 and composite hulls. 500 were ready and took part in the Normandy campaign, and many more were produced until the fall of Germany. Exact numbers are still elusive. Jane’s WWII vehicles records stated a total of 2346 Fireflies.