Pacific, Heroes and Leaders mod Expansion

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M3A5 Grant 2

M3 with British turret, Grant I, were the first tanks of this series to start the combat vis-a-vis the forces of the Axis. A first quota of 187 Grants I was sent in Egypt in 1942 and were versed in the 4th Armoured Brigade of the 9th Armoured Division and in 2nd and 22nd Armoured Brigades of the 1st Armoured Division within British VIIIth Army (Rats of the Desert). Their baptism of fire took place at the time of the battle of Gazala where they faced to distance the tanks of 21st Panzer, which they could maintain to distance thanks to their guns of 75 mm. Grants made it possible to the British to avoid a heavy defeat and strongly delayed the German advance at the time of the retirement of those towards El Alamein.
However Grants had undergone very heavy losses and in July 1942, the 1st Armoured Division had all the tanks available: 38 specimens accompanied by approximately 70 Crusaders. After the agreements consecutive to the law lease-lend of March, 250 M3 standard (Lee I) were delivered to the British forces. During the battle of Alam Halfa, the British could put at the combat within 8th and 22nd Armoured Brigades, 164 Lees/Grants which played a very significant defensive role there. At the time of the second battle of El Alamein, 210 M3 Lees were at the disposal of VIIIt Army of the Marshal Montgomery. After the victory in Africa, Lees and Grants were displaced and were sent in the Far East where they were useful within the Australian forces or within British XIVth Army and were used until the end of the war. It is true that they were hardly threatened by the Japanese models.

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US M4 75 DWG

Sherman was used as a basis for the realization of many conversions. Its chassis was used in particular for the realization of the majority of the US Tank Destroyers (tank destroyers) and others Self-Propelled Guns of the Second World War. These conversions are reported in the categories Tank Destroyers and Self-Propelled Guns.
Deep wading or deep fording is a technique used by some heavy semi-amphibious vehicles to traverse water that is several metres deep - the vehicle drives on the riverbed/lakebed/seabed and uses screens or a pipe (a snorkel) that reaches above the water surface for an air supply. Deep fording generally implies driving through water of such a depth that the vehicle is mostly or entirely submerged by the water, sometimes to several times the height of the vehicle itself, as well as a sealed crew compartment, complete with air supply for the crew. The M4 with amphibian exhaust device was a amphibious tank equipped with air intakes allowing the aeration of the engine and the exhaust.
In the Pacific the reconquest intensified, the Americans took again the Philippines into 44-45 and attacked Japan. Although the Japanese defended their skin dearly, Shermans met only seldom an opposition worthy of name of armoured tanks. The largest danger came from the ambushed Japanese anti-tank weapons in the abundant vegetation.

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US M10 Wolverines 3inch early turret

The Americans had an urgent need for specific tank destroyers having the mobility and the protection of an entirely tracked armoured tank. The role of tank destroyer were played by wheeled or half-tracked vehicles which did not have of the mobility and the protection necessary even of a satisfactory fire power. The first true test to provide a genuine tank destroyer to US Army was tried at the end of 1941, when one thought to mount the anti-aircraft gun of 76 mm on the chassis of Medium Tank M3. This model which was baptized T24 did not give satisfaction because of its high silhouette and an insufficient range of the gun. A version improved of this prototype was then developed under the name of T40. Although it was one moment envisaged after the tests to produce this last model under the designation of M9, the project was finally abandonned by the Tank Destroyer Board at the end of the summer 1942, because of insufficient mobility and speed.
In November 1941, one thought to transform into tank destroyer, the medium tank M4A1 equipped with a gasoline engine. But ultimately it was the chassis of the M4A2 equipped with a diesel engine which was selected and a model out of wooden of the new tank destroyer was produced in January 1942. The design of this new model was identical to that of the M4A2 but with a shielding side of 25 mm only and one new open turret (on the top and the back) accomodating an anti-tank gun of 76 mm. This model was baptized T35. During this time, reports of combat coming from the Philippines, mentioned all the advantages of n inclined shielding compared to the only thickness. The Tank Destroyer Board thus required a new design equipped with a superstructure whose less thick inclined walls (and thus lighter) offered an excellent protection all the same. On three proposals, only one was retained under the designation of T35E1.

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US M10 Wolverines 3inch mid turret

The Fisher Tank Arsenal (Chrysler) company worked on the two prototypes in January 1942. For the turret, it was determined to use a model with the walls welded in the place of a moulded turret, offering less ballistic protection. The models of production will thus use a new welded turret. In June 1942, the modifications had been made and the new vehicle baptized 76 mm Gun Motor Carriage M10 was ready for the production. The new turret was of pentagonal form (5 sides) although in the beginning a turret hexagonal (6 sides) had been envisaged.
The Tank Destroyer made its appearance on the assembly lines in September 1942 and will leave them in December 1943 with a total of 4993 produced specimens. Fisher Tank Division of Chrysler was the only firm to produce M10. The M10A1 was produced on the same assembly lines from September 1942 until November 1943, with one total of 675 specimens. The M10A1 was also produced with 1038 specimens by the Ford firm from October 1942 to September 1943, with a total of 1713 specimens of which 300 were assembled without turrets (Full Track Prime Mover M35).
M10 and the M10A1 were used by US Army within the Tank Battailons Destroyer but also in the allied armies of the United States like Great Britain, the Soviet Union and France.

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US M10 Wolverines 3inch late turret

The crew of the M10 Tank Destroyer is composed of five men, which the driver who sat in the front-left corner of the hull and his assistant sitting in the front-right corner. The two men had their own trap door (only one shutter assembled on hinge), on the roof of the superstructure.
For the remainder the internal provision of the equipment of M10 was traditional with the final command transversely assembled in front of the tank, protected by a nose cast in only one part (models of production), a transmission with six speeds (5-1) was installed between the two pilots. The other equipment: command pannel, radio, ammunition... were laid out on the overhangs of the tracks or the side walls of the lower hull or in front of the firewall of the engine.
The great innovation was the shape of the superstructure, which was made with tilted walls. The glacis of M10 was not equipped with machine-gun of 7.62 mm as for Sherman. For their vision the two drivers had a rotary episcope assembled on their trap door of access. The drivers had a second rotary episcope located in the front-left corner of the roof of the superstructure.
Still the radio antenna was located on the slope of right side of the superstructure in a recess located forwards. The sides were used still to store various equipment, mainly tracks links of replacement. The steel links were stored on two large racks located on the back part on the sides.

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US M10 Wolverines 3inch closed turret

The turret of M10 of pentagonal form (5 sides) was the part which will undergo the most modifications during the production. Various parts of the turret was assembled by weldings forming a tilted whole. The turret did not have a frontal wall, this one was replaced by a broad shield. The roof of the turret was open in its back part, which put the crew to the mercy of the bad weather and the enemy grenades or other projectiles and glares and especially to the air raids. In late, certain models will have their turret covered by an armoured superstructure. The shape of the turret evolvedduring the production, indeed this one was equipped very quickly with counterweight on the back parts to compensate the weight of the gun of 76 mm. Three types of counterweight were used giving rise to four different types of turret, the first being stripped. Turret was operated manually although it was envisaged the possibility to install an electric or hydraulic system which was never installed. It accomodated the three other men of crew, the gunner sitting to the left of the gun, the commander sitting to the right of the gun and the loader sitting behind the gun. The turret was equipped with a not very deep well of turret.
The armament of M10 was composed of the gun of 76.2 mm M7 assembled on M5 mounting. The weapon could make a complete traverse of 360° and had an elevation of 30° and a depression of 10°. Its maximum rate of shooting was of 15 shell per minute (6 were stored to the back of the turret). On the whole, 54 shells were stored in M10. The 76 mm gun could fire mainly piercing shells (AP for Armor Piercing), explosives (HE for High Explosive), smoke-producing. The useful range (effective) of a piercing shell was 914 m. The aiming was done via monocular glasses M38 which one sees the opening on the left side of the shield. If the open roof of M10 allowed to the commander an overall perfect visibility, for more safety, this one could use a monocular telescope installed on the wall of right side of the turret in order to avoid as much as possible to be to aimed by a marksman. The M10 did not have a secondary armament to ensure its local defense because it was not to mix to the close combats but to make fire in distance. However for more safety M10 were often equipped with n anti-aircraft .50cal machine-gun (12.7 mm) mounted on a pedestal to the back of the turret. Certain crews also mounted a .30cal machine-gun (7.62 mm) on a pedestal in front of the roof of the turret.

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US M10A1 Wolverines 3inch

M10 was propelled by a diesel engine GM 6046 of 12 cylinders (mounted by couple on line), with liquid cooling, of 13.9 L of displacement, developing 375 to 410 hp to 2100 rpm. The fuel tanks of M10 had a total capacity of 750 L what allowed it a maximum autonomy of 322 km on road (consumption: 233 L to the 100 km). M10 could reach 40(48) km/h on road what was appreciable. The back plate of the lower hull did not have an opening and was occupied for half by a broad exhaust with two pipes (by after replaced by a large deflector of exhaust). For the remainder it accomodated a hook of towing and two loops of towing (as for the nose). The rear deck was composed of large plates which that located behind the turret accomodated a small grid of ventilation whose two shutters were assembled on hinges. A fixed gun lock located on the rear dech made it possible to block the gun (pointed backwards) when the tank was transported by rail. The back plate of the superstructure was used to arrange various tools.
The M10A1 as for it was propelled by a gasoline engine Ford GAA of 8 cylinders (V), of 18 L of displacement developing 500 hp to 2600 rpm. The M10A1 transported to the maximum 764 gasoline L, what allowed it an autonomy of 210 km. The M10A1 could reach on road the maximum speed of 42 km/h.
The only external difference between the M10A1 and M10 was that the first had a larger grid of ventilation on the rear deck (always made up of two shutters assembled on hinges) and that the arrangement of the holes of supply of the fuel tanks was different. The M10A1 was based on the chassis of the M4A3 Sherman whereas M10 was it on that of the M4A2.

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US M10 Wolverines 3inch Sonic

The suspension of M10 and the M10A1 was identical, since one used the chassis of the M4A2 and M4A3 Shermans. This suspension consisted of each side of 3 bogie trucks (supports of road wheels) with vertical springs equipped each of two small road wheels with steel bindings, three return rollers (mounted to the back of the bogie trucks), a front sprocket-wheel and a rear idler. This suspension is known as "vertical" because of the vertical volute (VVSS).
The front sprocket-wheels will know two models, as well as the road wheels (5 to 6 branches). Each track was composed of 79 blocks of rubbers of 421 mm broad, joints between-them by external guides (connected to the pins). Rubber quickly wearing, several styles of steel protections were used to protect the rubber links.
Because of the prolongation on the sides of the superstructure to protect the top of the tracks, no equipment intended to compensate the too great pressure on the ground (dusckbills) could be assembled. The weight of the tank was less important than that of standard Sherman. To compensate the weak traction on soft ground, sheet metal (grousers) were sometimes embedded between each link and made office to some extent claws.
The M10 Tank Destroyer preserves the hull of the M4A2 Sherman but with a lighter shielding. On the other hand its superstructure is made entirely different, fromed with 4 large tilted plates welded between them. The principle of the tilted walls is to deviate instead to try to stop the ennemy projectiles and to thus prevent their explosion or the penetration of the shielding. This system allows a profit of weight because the effectiveness of the shielding depends more slope than the thickness, and it is the thickness of the shielding which makes the weight of the tank. The turret respects the same principles.

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UK Achilles Mk.IC

The tanks destroyers were also used in the Pacific but to a lesser extent. Their first actions were initiated in the Philippines (first battle) where the 75 mm m3 GMC faced within units of mobile artillery to the Japanese forces of invasion. M3 armed with the anti-tank gun of 75 mm was very much used by the Marines within Special Weapons Companies. M3s or SPMs (Self-Propelled Mounts) was used as fire support with the battalions of Marines with the case they would meet Japanese armoured tanks (what was rare). M3s used without the Pacific were over-equipped with machine-guns to push back the attacks of the Japanese infantrymen helped by the confined nature of the jungle. The Machines used these machines until the battle of Okinawa (Japan) during the summer 1945. The Marines also used of the 37 mm M6 GMC but they were quickly withdrawn from the service. Only 7 batalions of tank destroyers were used in the Pacific. M10s were used for the first time on the island of Kwajalein in February 1944 to support the 7th division of infantry. M10 on this quite particular theatre offered a support direct fire to the units of infantry. But with their opened turrets, M10s were very vulnerable to the attacks of the Japanese infantrymen and the shootings of the snippers easily dissimulated under cover of the jungle, just as the Japanese anti-tank weapons. One understood why the tanks as Sherman theirs were preferred. The tank destroyers however were very much used at the time of the reconquest of the Philippines to which three battalions took share. At the time of this battle, M18 Hellcat made its appearance in the Pacific. M36 as for it was never deployed in this zone of combat but one envisaged to use it for the invasion of Japan but Hiroshima and Nagasaki decided some differently.

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UK Achilles Mk.II

M3 GMC and M10 were also used by the British forces, like by the Free French Army (with M6 GMC). They were used mainly as support vehicle although British M10s rearmed with the gun of 17-pdr (77 mm) baptized Achilles were used like true tank destroyers at the time of the reconquest of France. Many British M3 GMCs were rearmed with the gun of 57 mm but were however never used with the combat. These renamed models T48 57 mm GMC were yielded to 650 specimens in the Soviet Union which used them in independent anti-tank battalions. The Polish free forces accepted from them some also at the end of the war.

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US M18 Hellcat 76mm

During the first part of the Second World War, the Americans wished to develop a light and fast hunter of tank. The first attempt was to install the gun of 76.2 mm on the chassis of M3 Stuart. At the end of 1941, one installed the anti-tank gun of 37 mm in an open turret on the chassis of the M9 light tank airborne Locust. This conversion was baptized T42. However, the gun of 37 mm was already obsolete at that time and one replaced it by the British gun of 6-pdr (57 mm) in spring 1942. This new model was baptized T49 and two prototypes were constructed by General Motor Buick Division. The tests showed however that the vehicle was too slow. The suspension was of Christie type, with volute springs. However the Tank Destroyer Command gave its preference to the gun of 75 mm and a new prototype armed with this gun was construct. It was identical to T49 but the gun of 57 mm had been replaced by the gun of 75 mm in an open turret. This model, baptized T67 was tested in November 1942 in Aberdeen. The gun gave satisfaction but it was not the case of the engine.
During, the development, the gun of 75 mm was replaced by the 76 mm M1 which had a more important thrust force. After the tests one decided to remove the T67 project and a new design, baptized T70 was developed, armed with the gun of 76 mm M1. General Motors received the order of 6 prototypes in January 1943 and the first was ready during spring 1943, the others being finalized for July. The double Buick engine of T67 had been replaced by a Continental R-975-C1 and the final transmission was done in front and either to the back as on T67.

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US M18 Super Hellcat 90mm

T70 was a very successful vehicle, in spite of some initial problems. The front shock absorber had to be doubled to compensate the weight of the tank. The lifespan of the tracks was hardly famous and works were carried out to improve it. After improvement of the design, the production began immediately at General Motors Buick Division in July 1943. In March 1944, T70 was renamed 76 mm Gun Motor Carriage M18. The 18 was also called Hellcat. T70 was finalized for July 1943. It started directly production on the assembly lines of Buick Division of General Motors. From July 1943 to October 1944, 2507 specimens were produced under the designation of 76 mm Gin Motor Carriage M18 (name obtained in March 1944).
In spring 1945, the gun of 90 mm M3 was very largely spread and it was decided to mount this gun on M18 Hellcat. As it was already assembled on M36 Jackson, one decided simply to mount the turret of M36 on M18. The circular had to be increased of 5 cm and modifications were brought to the arrangements of ammunition. To effectively compensate the effects of the shootings of the gun of 90 mm on the chassis, a muzzle brake was obligatory. However with each shooting the tank moved back of 60 cm! To compensate the increase in weight one thought to use broader tracks. However end of the war in August 1945 put a term at the development of this very promising design.

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US M36 Jackson 90mm

While M10 started production, the Germans put on the battle fields new more powerful and better protected tanks. Although excel, the gun of 76 mm had become insufficient to pierce at distance the shielding of the new German panzers (Tigers, Panthers). T53 and the T53E1 are the first attempts to mount the anti-aircraft gun of 90 mm on an entirely tracked mounting. An order of 500 specimens was carried out then finally cancelled because of the low mobility, instability, the insufficient protection of the crew, the too high silhouette and the too light weight to take the recoil, of the prototype. The project was cancelled in spring 1944 to the profit of M36.
One thus thought to rearm M10 and M10A1 models with the anti-aircraft gun of 90 mm because the chassis gave whole satisfaction. A version of this gun was installed in the turret of M10 during the summer 1942 to check the feasibility of this conversion. However the gun of 90 mm weighed approximately 150 kg more than that of 76 mm what caused some problems of balance on the level of the turret of M10. The best solution was to design a very new turret what was made. Work on the new turret began at Chevrolet in spring 1943 and Ford assembled two mild steel models based on M10 and the M10A1. The new turret was inspired by the T23 turret which equipped Shermans(76) and was equipped with a broad bulge (strongly armoured) to the back which compensated the weight of the gun. This bulge was also used to store ammunition of 90 mm. This new turret was overall better armoured than that of M10. In November 1943, the design was finalized and Fisher Tank Arsenal accepted a contract for 500 specimens based on the T71E1 (hull of the the M10A1 gasoline). Fisher didn't have the sufficient number of chassis to convert the M10A1 (hardly more than 200), it was thus necessary to build the new ones. The Massey Harris company was called in reinforcement to supplement the initial order. In June 1944, the T71E1 was officially renamed M36.

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US M36B1 Jackson 90mm

The T71E1 was standardized in June 1944 under the designation of 90 mm Gun Motor Carriage M36. But it had already been its appearance on the assembly lines of Fisher Tank Division (Chrysler) in April 1944. A total of 300 specimens were produced in this factory starting from this date, until July of the same year. Three other manufacturers were put at the task: first of all Massey-Harris Co which produced of them 500 between June and December 1944, then Alco (American Locomotive Co.) who produced of them 413 between October and December 1944. From this moment the production of M36 known a stop but will take again course for two months in May-June 1945 at Montreal Loco Works where 85 specimens were produced. On the whole 1298 specimens of M36 were manufactured in the one year space.
M36 was equipped with the gasoline engine of the M10A1. The design of the hull was identical to that of the standard M10A1. At the interior the brackets of reinforcement of the superstructure were moved forwards providing more space to the ammunition of 90 mm. The engine compartment was equipped with an auxiliary generator and a modified electric installation. The firewall was also modified, like trap doors of the floor. The only notable differences come from the turret. The provision of the crew was different also. Indeed the gunner sat to the right of the gun, the commander sat behind him and the loader sat to the left of the gun.
The turret of M36 was equipped with a partial well of turret.The M36B1 with the original hull of the M4A3(75)W was produced to 187 specimens only by Fisher Tank Division between October and December 1944. The M36B2 was as for it produced to 672 specimens by Alco and 52 specimens by Montreal Locomotive in April-May 1945. These two models were only conversions of M36.

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US M36B2 Jackson 90mm

Because of the weight of the gun the turret of M36 was equipped with an assisted system of traverse, in addition to the manual system. The general aspect of the turret was round and nonangular as that of M10. It recalls in fact, a little, the T23 turret which will equip Shermans(76). It was equipped with a broad strongly armoured bulge, whose weight counterbalanced that of the gun and who accomodated ammunition of 90 mm arranged in tubes.
M36 was armed with the gun of 90 mm M3 on M1 mounting (with broad round shield) with an elevation of 20° and a depression of 10°. On the whole M36 accomodated 47 shells of 90 mm, mainly piercing shells, but also some high-explosive shells and smoke-producing shells. This weapon could with shells with high velocity (HVAP - High Velocity Armor Piercing) pierce still 154 mm of shielding to 2000 mm thanks to an initial speed of 1021 m/s! It was clear that no German tank was to the shelter of a such weapon. To supplement its armament, M36 was equipped with a .50cal machine-gun (12.7mm) for its anti-aircraft and local defence mounted on a pedestal on the back bulge.
The shielding is made up of laminated steel plates welded between them. The shielding of the hull and the superstructure are nearly identical to that of M10 and respect the same principles. But that of the turret is higher as the figures attest it below.
Because of the lack of hull of M10A1 available, one also used the hulls of M10 with diesel engine (M36B2) and hulls of the M4A3(75)W with gasoline engine (M36B1). This last model was very different from both others with a design of hull of Sherman.
The M36B2 was equipped with the hull of M10 with diesel engine. Its engine was a GM 6046 of 12 cylinders (mounted by couple on line), with liquid cooling, of 13.9 L of discplacement, developing 375 to 410 hp to 2100 rpm. It is distinguished from M36 thanks to its grid of ventilation of small size on the rear deck of the superstructure. It was equipped with a muzzle brake to double deflector and with an armoured superstructure covering the turret to protect the crew.

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M8 Scott 75 mm Howitzer

In 1941-42, US Army tank battalions were divided between light or medium battalions. The first were equipped with M3/M5 light tanks and the second of M3/M4 medium tanks. In order to provide a mobile artillery support to the light battalions, one decided to produce a light motorized howitzer. Moreover, there was a request for a self-propelled 75 mm howitzer for the infantry cannon companies.
One firstly tried to adapt the chassis of M3 light tank but conversion was a failure and it was finally the chassis of M5 light tank which was selected. The howitzer of 75 mm was assembled in a broad turret open to the top and also equipped with a circular for anti-aircraft machine-gun of 12.7 mm. The T47 prototype (or T17E1) was finalized and produced by Cadillac Motor Car Division of General Motors Corp. T47 was accepted for the production in 1942 as M8 75 mm Howitzer Motor Carriage.
M8 was manufactured by only Cadillac Motor Car Division of General Motors Corp.
A total of 1778 specimens were produced between September 1942 and January 1944.
M8 had a crew of 4 men: the driver sitting in the front-left corner of the hull, its assistant sitting in the front-right corner and the commander-loader and the gunner sitting in the turret. The first two men had sat behind the final command device and automatic transmission (Hydramatic) with 5 speeds (4-1). The steering was with controlled differential and was done via the steering levers while slowing down on one of the two tracks. The hull of M8 was nearly identical to that of M5. The glacis was inclined, the upper part was in the shape of reversed trapezoid and was welded whereas that lower was bolted. However contrary to M5 the glacis of M8 did not comprise machine-gun of hull. The access was done via two trap doors assembled on hinge either on the roof of the superstructure but on the glacis itself to even provide space necessary to the broad circular (1.38 m) of the turret.
M8 was equipped with a broad turret open to the top. Traverse was manual. The armament consisted of an howitzer of 75 mm M2 or %3 assembled on M7 mounting and of a machine-gun of 12.7 mm assembled on a circular in the back-right corner of the turret. The howitzer will full traverse shooting capacity, had a depression of 20° and an elevation of 40°. M8 embarked 46 shells of 75 mm. A fastener of trailer was assembled on the back plate of the hull to tractor draw a trailer of ammunition. The commander who also had the function of loader had sat in the right part of the turret whereas the gunner had sat in the left part.
M8 as M5 was equipped with the engine Twin (double) Cadillac Series 42 of 2 X 8 cylinders (V) developing on the whole 296 hp to 3200 rpm. M8 reached the maximum speed of 58 km/h and had an autonomy of 161 km. M8 like M5, because of dimensions of the Cadillac group-engine had an imposing rear deck. The elevated rear deck was easily recognizable. The access to the engine was done is via the trap doors of the upper rear plate of lower hull or for a more significant maintenance by the plates of the rear deeck which were then dismounted.
M8 was only used by US Army in Western Europe, Italy and in the Pacific. Whereas M8 was brought into service in 1944. The light and medium tank battalions were removed and remelted in only one composite battalion composed of a light tank company and three medium tank companies. These units will use Shermans(105) to play the role of M8 HMC and this one disappeared quickly from strengths of the Tank Battalions.
M8 HMC was however still used as assault gun in the cavalry reconnaissance squadrons. One counted 8 M8 HMC in the squadrons attached to armoured divisions, and six in each non-divisional squadron. During the campaign of Western Europe, each corps had a group of reconnaissance of cavalry, being composed of several squadrons. These units of cavalry played a vital role. They have the uncomfortable job to probe the ground before the arrival of the tanks, which meant that its elements were the first to undergo the fire of the enemy at the time of ambushes or ennemy offensives. The squadrons of cavalry were also employed to ensure the safety on the flanks during the mobile operations. These squadrons were equipped with M8s and M5A1s. When the Germans arrived, these machines moved back and called Shermans to the rescue because they were not conceived to face to Panthers and Tigers.

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M7 Priest 105 mm Howitzer early

Following the experiment of the installation of howitzer of 105 mm on half-tracked vehicles, US Army decided to realize an entirely tracked version. The project of the motorized howitzer of 105 mm began in 1941. The standard field howitzer US M1A2 was installed in the center (a little shifted towards the right) of an open superstructure assembled on the chassis of Medium Tank M3.
aldwin presented two T32 prototypes, which after the addition of a cupola for an anti-aircraft machine-gun of 12.7 mm were standardized as M7 HMC in February 1942.
M7 HMC was produced by the firms American Locomotive Co (Alco) and Federal Machine and Welder Co. Whereas the M7B1 was produced by Pressed Steel Car.
A total of 3314 M7 were produced between April 1942 and 1944 whereas 826 M7B1 were produced between March 1944 and February 1945.
One tried to install on a M7B1, the British gun of 25-pdr Mark II (88 mm). But before the T32 prototype was finalized, best designs had been born.
The crew of M7 was composed of 7 men: the driver who took seat in the cockpit in the front-left corner of the hull, the commander and 5 gun crewmen which took seat in the compartment of combat. The driver had his commands pannel placed in front of him and the radio equipment was located on his left on the top of the left track. The driver had for his vision an armoured window on the left part of the frontal plate of the superstructure. The final command device was assembled transversely in front of him and the transmission on its right. As on M3, the transmission of the synchromesh type had 5 forward speeds and 1 reverse speed. The whole was protected on the first models by a nose in three parts bolted between them which was replaced on the last by a cast nose.

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M7 Priest 105 mm Howitzer late

The gun of 105 mm M2A1 was assembled on M4 mounting in the compartment of combat in the center protected by an armoured superstructure opened with the top. Mount was shifted slightly on the right. The howitzer had a traverse limited to 15° on the left and 30° on the right and had a depression of 5° and a elevation of 35°. M7 embarked 69 rounds of 105 mm arranged in racks on the overhangs of the tracks. Armament was supplemented by a .50cal machine-gun (12.7 mm) mounted on a circular cupola to the right of the gun which made a bulge on the right side of the superstructure. This cupola making think to a pulpit of priest, M7 was quickly baptized "Priest" (priest).
The engine of M7 was the gasoline engine Wright (Continental) R975 C1 of 9 cylinders (radial), of 15.9 L of cubic capacity developing 340 to 400 hp to 2400 rpm. This engine allowed on road a maximum speed from 34 to 39 km/h for an autonomy of 190 km. The back plate had a access double-door assembled on hinges. It was surmounted by a rectangular deflector of exhaust. The rear deck covering the engine compartment was composed of 2 large plates and a grid of ventilation. On each side of the rear deck on the mudguard one found two large cases of arrangement surmounted each one of a basket. Upper rear plate which surmounted the deflector of exhaust accomodated various tools and was flanked of the two back headlights. The remainder of the tools were laid out on the rear deck.
For model M7B1 one used the hull of Sherman M4A3 which was equipped with the engine Ford GAA (gasoline), 12 cylinders (mounted on line), 13.9 L of cubic capacity, developing 375-410 hp to 2100-2400 rpm, with air cooling. The quantity of embarked gasoline was the same one, as well as autonomy. On the M7B1 the rear deck covered all the width of the tank. It was composed of two plates and between the two, an access grid with two shutters assembled on hinges. The trunks of arrangement as well as the back headlights were assembled on the tilted sides of the rear deck. The back plate of the superstructure which made also all the width overhung a broad deflector of exhaust. The rear plate of the hull had only one small trap door assembled on hinge flanked of the two pipes of exhaust.

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M7B1 Priest 105 mm Howitzer

The Americans used M7 on all fronts: North Africa, Italy, Western Europe and the Pacific. The Marines intensively used it in Okinawa, especially as transport of troops (13 men took seat on board).
M7 offered an appreciable mobility to the 105 mm field howitzer. It was the counterpart of German Wespe in the category of armoured Artillery. As the machines of the same type M7 was not a weapon of contact because its open superstructure and its weak shielding made of it an easy prey even for infantrymen. The standard use was to make fire into battery (section of M7) since the back lines to ram the enemy positions as a battery of standard howitzers would do it.
The British troops were equipped with M7. The first 90 specimens were sent in Egypt in 1942, just before the beginning of the second battle of El Alamein. They is the British who gave to M7 its nickname of "Priest" in reference to the cupola in the shape of pulpit of church. M7 was used in North Africa and Italy by British VIIIth army.
The British also ordered a version equipped with their own field gun which was baptized Sexton and fought with this model in Western Europe after the first engagements in Normandy. Let us note that the Free French Army was also equipped with M7.
To realize an entirely tracked transport of troops, the British modified 102 M7 between October 1944 and April 1945. The 105 mm and the racks of ammunition were simply withdrawn to release the space of the compartment of combat. This conversion baptized Kangaroo could in more of its two crewmen carry 20 infantrymen or a mortar and its crewmen.
The British also realized a version of command, Priest Op. As Kangaroo the compartment of combat was released to accomodate radio sets.

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M37 Priest 105 mm Howitzer

Wishing a mobile mounting more compact and more economic than M7 Priest (based on Medium Tank M3) for the howitzer of 105 mm, the Americans developed T38 on the basis of chassis of the Light Tank M24 Chaffee. T38 was standardized in January 1945 as M37 105 mm HMC and made for the first time its appearance only in September 1945. Only 150 specimens were built by American Car & Foundry Co and Cadillac.
The crew of M37 was composed of 7 men: the driver sitting in the front-left corner of the hull, the commander and the 5 gun crewmen installed in the compartment of combat. The front cockpit was occupied by the pilot, the Hydramatic transmission comprising 12 speeds (8-4) and the final command device which transmitted the power to the front sprocket-wheels mounted perpendicular to the transmission and the instruments of control and steering. For his vision the pilot had a rotary episcope on the only oval trap door of access preserved compared to M24. The inclined nose of M24 was preserved just as it is, safe forthe machine-gun assembled on ball which was removed. The compartment of combat entirely occupied all the remainder of the tank covering the engine compartment to the back. This compartment of combat vaster than that of M7 Priest allowed a greater storage of ammunition. Indeed M37 transported 126 projectiles of 105 mm instead of 69 for M7. The armament consisted of an howitzer of 105 mm M4 assembled on M5 mounting assembled in front of the compartment of combat a little shifted on the right and a machine-gun of 12.7 mm installed on a cupola of shooting located at the right side of the principal weapon. As for M7, this cupola in the shape of pulpit of church got for M37 the nickname of Priest (priest)