Article originally published on Tanks Encyclopedia: http://www.tanks-encyclopedia.com/
Author: David Bocquelet
The M3 Lee/Grant never achieved the fame of the Sherman. This was due to its very roots and the role it played during the war.
Born as a replacement for the unsuccessful M2 Medium Tank (1938), which never left the American soil, the M3 Lee was designed and equipped in a rush. When war broke out in Europe in 1939, the USA was far from ready to enter the fray.
Its tank design was evolving through a peacetime, post-crisis context, and tactical thinking was inherited from WWI.
400 tanks were available then, mostly Light Tank M2 models.
The result of the blitzkrieg in France came as a real surprise and immediately triggered a complete re-thinking of US tank design. Shortly after the Battle of Britain was over, war engulfed North Africa. The British industry was not able to deliver enough tanks to defend both the homeland and the empire, and notably its vital crossing points, like the Suez Canal.
As the Lend-Lease act was passed, on March 11, 1941, President Roosevelt famously declared that the USA should become the “arsenal of democracy“. And the M3 Lee quickly turned into its most tangible symbol.
Design of the M3 – The “Iron Cathedral”
The M3 Lee design process began in July 1940, as a derivative of the T5 Medium Tank prototype, the T5E2.
By then, the M4 Sherman, a 75 mm (2.95 in) armed medium tank, was already scheduled for production. But many features, like the full rotating turret design, were far from ready and the US industrial capacity not mature enough for the required production values. The T5E2 design came as an interim, fast-to-production model.
The rushed design then entered production, being required both by US Army needs and the United Kingdom’s demand for 3,650 medium tanks (by then a British proposal for US-built Crusaders and Matilda was rejected). It was basically a scaled up M2, with better armor, a much higher and wider hull, in order to mount an offset 75 mm (2.95 in) gun in a traversable sponson on the right side.
The initial plans called for a full traverse turret equipped with a single AA Cal.30 (7.62 mm). The 75 mm (2.95 in) was meant to deal both with static ground targets and other tanks, with its armor-piercing projectiles and good velocity. High explosive shells were carried as well.
However, the 37 mm (1.46 in) gun was still favored in the AT role, and one was added in a small turret on top of the superstructure.
An upper cupola was initially designed to house a Cal.30 (7.62 mm) machine-gun, giving this model its cartoonish, caricatural appearance, bristling with guns in turrets and sponsors, much like a battleship.
As customary for US tanks by that time, secondary armament comprised between three and eight cal.30 (7.62 mm) model 1919 machine-guns. The tracks, most of the suspension system, road wheels and return rollers were all borrowed from the M2 to ease production.
The main difference was a three bogie train and redesigned suspension.
Large and roomy, the M3 Lee accommodated a large transmission unit, running through the crew compartment. It was served by a synchromesh, 5 speeds forward, 1 reverse gearbox, and steering was obtained by differential braking.
The vertical volute suspension incorporated a self-contained return roller, which was no longer fixed to the hull.
This feature was meant for easier maintenance and repair. The turret was geared by an electro-hydraulic system, powered by the main engine, also providing pressure for the main gun stabilizer, and the turret could make a full traverse in less than 15 seconds.
The main gun was operated by a loader and gunner (with a spade grip) and targeting done through an M1 telescope, mounted right on the sponson roof. The maximum range was 2700 m (3000 yds). An M2 telescope served the secondary gun, which had a maximum range of 1400 m (1500 yds). This 37 mm (1.46 in) gun was operated with geared handwheels for traverse and elevation.
The normal provision was 46 rounds for the 75 mm (2.95 in), 178 for the 37 mm (1.46 in) and 9200 for the machine-guns.
The maximal configuration included machine guns mounted in the upper turret, lower coaxial, commander cupola, rear external AA mount for a single M1919 A4, and even four hull machine-guns in sponsons, fitted in the four corners of the superstructure. In practice, they were rarely seen.
The powerplant was an aircraft based Wright Continental, with high-octane gasoline, air cooled, which was also a perfect choice for a speedy production, as no dedicated engine powerful enough was available then. The upwards position of the transmission, not helped by the tall engine, which sat high on the rear part of the hull, forced the entire casemate to be raised.
The overall design was incredibly tall, 10 feet (3 m) high, which later arose as for its major drawback on the battlefield.
The Germans nicknamed the M3 a “splendid target” and the Americans the “iron cathedral”.
The British order of M3 Lee
The M3 Lee was not the initial choice of the British commission. The wooden mock-up was built when the first plans were ready and presented in 1940.
Several flaws immediately appeared, among them, a high profile, sponson gun, riveted hull, insufficient armor and a hull mounted radio.
But as production was scheduled to start quickly after the final prototype was ready, and hoping for improvements on later versions, an initial order for 1250 M3s was placed for a total 240 million dollars, and the production shared between three US companies, Pressed Steel Car, Pullman, and Baldwin.
These three built the British models (soon called “Grant”, after the famous Union general), while the US models (called “Lee”, after his famous Confederate antagonist) were produced by the Chrysler Detroit Tank Arsenal, and American Locomotive (ALCO) at Schenectady, New York.
The turrets were cast by Union, General Steel Casting, ASF, and Continental.
This explains why there were so many differing details within the two main versions -M3 and M3A1- and between the British and US models. The British prototype was ready in March 1941. It included a distinctive turret back bustle to accommodate a Wireless Set No. 19 radio, stronger armor and no machine-gun cupola, replaced by a simple hatch.
The armor increase was not initially planned but introduced as soon as new reports of German anti-tank capabilities were available. The initial crew included a driver, commander, gunner and loader, upper gunner, a machine-gun servant and a radio operator. The British model didn’t include the radio operator. Later, the US crew numbers were also reduced to six and even five in 1942, as one of the gunners became the radio operator.
Production from the M3A1 to the M3A5
Ready as it was for mass-production, 4724 units M3s were built in the first batch, starting from mid-1941, and the second batch of 1334 units was built until December 1942, encompassing the M3A1 to the M3A5 versions. The M3A1 (Lee II) featured a cast rounded hull, with a low profile turret and slightly thicker armor.
Only 300 M3A1s were built, followed by the M3A2 (Lee III), with a welded but sharp angled hull, of which only 12 units were produced. The M3A3 (also called Lee IV and V), featured a welded hull, a pair of GM 6-71 diesel, and fixed or eliminated side doors (322 units).
The M3A4 (Lee VI) had a stretched welded hull and a new Chrysler A57 multibank engine, a strange assembly of five 6-cyl L-head car engines mated to a common crankshaft, boasting a final 21 liters capacity with 470 bhp and a lot of torque. This was well-appreciated, as the initial model was criticized for being underpowered.
Only 109 of these M3A4 were built. The last production (591 units), mostly fielded by the British Army, was the M3A5, equipped with the twin GM 6-71 diesel, but with a riveted hull and Lee turret. Strangely, they were called “Grant II” in British service.
Due to the many contractors involved, notably the cast turret foundries, these variants showed further variety in the shape of the hull, turret, and details, notably due to different casting procedures.
The M3 Lee, as a basis for further developments, was incredibly successful. Not only did it allow the long-awaited M4 Sherman to be designed and produced faster, thanks to the many parts it shared with the M3 Lee, but the same chassis also served as other vehicles.
These included the Canadian Ram tank, the 105 mm (4.13 in) Howitzer Motor Carriage M7, better known as the M7 Priest, 155 mm (6.1 in) Gun Motor Carriage M12, the Kangaroo armored personnel carrier, and the Sexton Mk.I self-propelled gun.
Many were also converted as recovery tanks, the model M31 (also called Grant ARV in British service), and the M31B1 and M31B2, based, respectively, on M3A3/A5 versions. The M31 was fitted with a dummy gun and turret, a crane and a towing apparatus with a 27 ton (60,000 lb) winch installed. The M33 Prime Mover was a conversion of former towing versions as artillery tractors (109 units in 1943-44).
The British variants were the Grant ARV, an armored recovery vehicle obtained from disarmed Grants Mk.Is and Mk.IIs, the Grant Command, equipped with map table, extra radio, and dummy guns; the Grant Scorpion III, a mine-cleaning vehicle equipped with the Scorpion III flail, and its variant the Scorpion IV; and eventually the Grant CDL, which stands for “Canal Defence Light”, featuring a powerful searchlight and a machine gun.
355 were produced in all, which was also registered in US Army service as the “Shop tractor T10”.
A single Australian conversion (800 had been transferred by 1942) was the BARV, a beach recovery vehicle, which used the M3 chassis. Probably the last of these versions was the Australian Yeramba Self Propelled Gun, with 12 units adapted from the M3A5 in 1949.
The M3 Lee in action
With a production running only one year and a half and an obsolete, awkward design, the M3 Lee was not supposed to be a frontline tank during the entire length of the conflict. But it nevertheless saw service until the very end, thanks to some qualities, redeployment in more suitable campaign theaters, and conversions to other duties.
The British, although reluctant, pushed for it since it was the only model suitable for instant mass-production, and it became the warhorse of the British VIIIth Army during 1941-42, especially during the worst period of the campaign.
Although the high silhouette and main gun position were despised, the Lee/Grant was reliable, very sturdy, had good armor and, overall, generous firepower. Through Lend-Lease, 2,855 units were sold to the British and 1396 were supplied to the USSR.
The British M3 Lee in combat
First engagement came with the disastrous Battle of Gazala, which did not diminish the role played by these tanks (at that time, the main British design, the Crusader, only had a 37 mm/1.46 in gun and minimal armor).
Grants and Lees were well-used in each major engagement of the African campaign, from El Alamein to the end of the Tunisian campaign, in mid-1943.
By then, gunned Panzer IIIs and IVs proved deadly and the M3 Lee had been gradually replaced by more capable Shermans and British designs armed with the QF 6 pounder.
Since there were battle reports of the M3 throughout mid-1942 to November, when the first US forces arrived in Africa, most variants (A1 to A5) were attributed to British requirements. British M3s were sent to the India/Burma theater as soon as they received the new M4 Sherman.
About 1700 transferred units gave an excellent account of themselves during all the campaign, from 1943 to 1945.
800 were taken over by Australian forces, and 900 by Indian forces. They formed the bulk of the Fourteenth Army (with Indian crews), with battle honors such as the fall of Rangoon, the battle of Imphal (proving pivotal in their task), were they battered out the Imperial Japanese Army’s 14th Tank Regiment.
The US Army M3 Lee in combat
The baptism of fire of the US Army M3 came during Operation Torch, under light opposition from Vichy French forces, but they were more heavily tested during the race for Tunis in December, and the battle of Kasserine Pass. By then, only one operational unit was equipped with M3s, the 2/13th Armored Regiment of the 1st Armored Division. The last surviving units had been replaced by M4s at the beginning of 1943.
Ironically, many depleted units equipped with M4 were reequipped with M3s, notably the 3/13th Armored Regiment.
The other unit entirely equipped with M3s was the 751st Tank Battalion of the 34th Infantry Division. By the time of Operation Husky (campaign of Sicily), the M3 Lee was still in use by these units, but once again, the losses were replaced by M4s, and by mid-1943, all M3s in this sector had been phased out from active units.
In the Pacific theater, a single unit equipped with M3s, the 193rd Tank Battalion, deployed its M3A5s fitted with wading gear in Butaritari, part of the Makin Atoll (Gilberts Islands), in November 1943, for infantry support against pillboxes and the rare Japanese light tanks encountered. None were ever used by the US Marine Corps. In March 1944, US Army Ordnance declared the M3 obsolete.
Most M3s were converted for other uses, cannibalized for spare parts, affected to drilling center units. For its odd-looking appearance, the M3 was shown in movies like 1943’s “Sahara”, starring Humphrey Bogart, and in its remake in 1992, and in 1979 in Spielberg’s “1941”. Perhaps 50 have survived until today in various museums and private collections, including a dozen in running conditions.
The Soviet M3s in combat
Part of the Lend-Lease plan, a shipment of 1300+ M3s were delivered by convoy to Murmansk and put in operational use by Soviet armored brigades, notably around Leningrad and Stalingrad.
The tanks were designated as the M3S, the S standing for Sredniy, meaning Medium. For a long time, it was believed the tanks sent to the Soviet Union were M3A3 and A5 Diesel powered sub-variants. But recently found documents suggest that all M3s sent to the USSR were the standard model, fitted with the Continental radial engine.
The Soviets quickly realized this model was not a winner and, after one year of hard fighting realized it was hopelessly outdated.
Surviving vehicles (infamously called “A grave for Seven Brothers”) were retired from front-line operations and shipped to quieter or less well-defended sectors, like the Arctic front.
There, they took part in the Lista and Petsamo-Kirkenes offensives, where they encountered second-rate German tanks, mostly former French captured models. Some M3s were also captured by the Wehrmacht in 1942 and served as the Panzerkampfwagen M3(r).
The Soviets also received 130 M31 Tank Recovery Vehicles, based on the hull of the M3. Some of these were the M31B1 Diesel powered variant.
Another way of hiding your tank, besides camouflage, was to change its shape. This type of deception tactic had been used by the Royal Navy in WW1. They changed the outline of destroyers to look more like merchant ships.
When the WW1 German U-boat surfaced to attack the ship with its main gun the screens would drop to enable a full broadside of high explosive shells to be fired at the submarine. These type of ships were called ‘Q’ boats.
During Operation Bertram, in the months leading up to the second Battle of El Alamein in North Africa in September – October 1942, camouflage and dummy vehicles were used to deceive the Germans where the next attack was going to come from. Real tanks were disguised as trucks, using light “Sunshield” canopies.
To achieve the deception, trucks were parked openly in the tank assembly area for some weeks.
Real tanks were similarly parked openly, far behind the front. Two nights before the attack, the tanks replaced the trucks, being covered with “Sunshields” before dawn.
*This article was originally published at www.tanks-encyclopedia.com