M10 Tank Destroyer

Infobox Weapon
name=3-inch Gun Motor Carriage M10


caption=
origin=USA
type=Tank destroyer
is_vehicle=yes
length=6.83 m (22.41 ft) "(w/ gun)"
5.97 m (19.6 ft) "(w/o gun)"
width=3.05 m (10 ft)
height=2.57 m (8.43 ft)
weight=29.6 tonnes (65,000 lb)
suspension=Vertical Volute Spring Suspension (VVSS)
speed=51 km/h (32 mph)
vehicle_range=300 km (186 mi)
primary_armament=3" (76.2 mm) Gun M7
54 rounds
secondary_armament=.50 cal Browning M2HB machine gun
300 rounds
armour= 9 to 57.2 mm (0.3 to 2.3 in)
engine=General Motors 6046 Twin Diesel 6-71
engine_power=375 hp (276 kW)
pw_ratio=12.5 hp/tonne
crew=5 (Commander, (3×) gun crew, driver)

The 3-inch Gun Motor Carriage (GMC) M10 was a United States tank destroyer of World War II. US troops also called them "TDs" (a nickname for any tank destroyer). When used by the British Army the M10 was designated the "Wolverine",dubious [ [http://www.audiemurphy.com/m10.htm M10 Tank Destroyer ] ] [ [http://original.britannica.com/eb/article-9105583/tank-destroyer tank destroyer - Britannica Online Encyclopedia ] ] from the official designation given by the British to their Lend-Lease 3-inch GMC M10s.

Development

During World War I and through the end of World War II, armored warfare doctrine held that armored vehicles should be designed to fulfill one of two roles: infantry support and anti-tank warfare. Because the roles were seen as mutually exclusive, separate vehicles were designed for each role. In some nations such as Britain, these were termed infantry tanks and cruiser tanks. Germany fulfilled the roles initially through the development of the Panzer III for anti-tank warfare, and the Panzer IV for direct fire support, and later by developing specialized turretless assault guns and tank destroyers. In the United States Army, tanks were seen as infantry support just as they had been in World War I, while anti-tank warfare was to be performed by tank destroyers. Though equipped with turrets (unlike most tank destroyers of the day), the typical American design was more heavily gunned, but more lightly armored, and thus more maneuverable, than a true tank. The idea was to use speed and agility as a defense, rather than thick armor, to bring a powerful self-propelled gun into action against enemy tanks.

The 3-inch Gun Motor Carriage T35 was the prototype of the M10. It was equipped with a 3-inch (76.2 mm) gun in a new sloped, circular, open-topped turret, developed from the Heavy Tank T1/M6 turret, and mounted on an early-production Medium Tank M4A1 hull.

This prototype was further developed by sloping the hull, using an M4A2 chassis, and replacing the circular turret with a pentagonal version; this model was designated 3-inch Gun Motor Carriage T35E1. In June 1942 the T35E1 was finalized as the 3-inch Gun Motor Carriage M10 and ordered into full production.

A British variant, designated "Achilles", was developed to mount the successful 17-pounder anti-tank gun in a modified turret. It was used by the British, Canadian and Polish armies in Italy and North-West Europe. [ [http://www.armyvehicles.dk/m10achilles.htm M10 Achilles IIC] ]

Armament

The M10 used a Medium Tank M4A2 chassis (M10A1s used M4A3 chassis) with an open-topped turret mounting a 3" (76.2 mm) Gun M7. This gun fired the AP (Armor Piercing) M79 Shot that could penetrate 3 inches of armor at 1,000 yards at 30 degrees from vertical. Other ammunition carried throughout its service life included the APCBC (Armor Piercing Capped Ballistic Cap) M62 Projectile, HVAP (High Velocity Armor Piercing) M93 Shot, and APHE (Armor Piercing High Explosive); 54 rounds of 3-inch ammunition were carried. The rear of the turret carried a large counterweight which gave it a distinctive shape.

A .50 cal Browning M2HB machine gun could be mounted on the top rear of the turret for use against enemy infantry and for anti-aircraft use, along with 1000 rounds. The crew were also equipped with their personal weapons for self-protection.

Combat use

The M10 was numerically the most important U.S. tank destroyer of World War II. In its combat debut in the North African campaign, the M10 was successful as its M7 3-inch gun could destroy most German tanks then in service. The M10's heavy chassis did not conform to the tank destroyer doctrine of employing very light high-speed vehicles, and starting in mid-1944 it began to be supplemented by the 76 mm Gun Motor Carriage M18. Later in the Battle of Normandy the M10's gun proved to be ineffective against the frontal armor of the newer German Tiger and Panther tanks, and although it remained in service until the end of the war, by the fall of 1944 it was beginning to be replaced by the improved 90 mm Gun Motor Carriage M36. In the Pacific, US Army M10s were used for infantry support but were unpopular due to their open-topped turrets, which made them more vulnerable than a fully-enclosed tank to Japanese close-in infantry attacks.

Approximately 54 M10s were supplied to the USSR though their use by the Red Army service is largely unrecorded. The M10 also equipped units of the Free French Army; one M10 named "Sirocco", part of the "Régiment Blindé de Fusiliers Marins" composed of French sailors, famously knocked out a Panther on the Place de la Concorde during the liberation of Paris. British M10s were designated 3in SP Wolverine and saw action in Italy and France, including some upgunned with the more effective 17-pounder gun (designated 17pdr SP Achilles).

The M10's open-topped turret left the crew vulnerable to artillery and mortar fire as well as infantry close assault, especially in urban combat and wooded areas. By the end of the war its armor was too thin to provide protection from the newer German tanks and anti-tank guns. The other main disadvantage of the M10 was its very slow turret traverse, as the turret was not powered and the crew was required to hand-crank the turret, taking approximately two minutes to rotate 360 degrees. U.S. tank destroyers fired much more high-explosive shells than anti-tank ammunition, indicating that they were employed much like the tanks they were supposed to support.

Variants

* 3-inch Gun Motor Carriage T35 "(Prototype)": Early production Medium Tank M4A2 chassis.
* 3-inch Gun Motor Carriage T35E1 / 3-inch Gun Motor Carriage M10 (3in SP, Wolverine in British service [British and American Tanks Of World War Two: The Complete illustrated history of British, American and Commonwealth tanks: 1939–1945, Peter Chamberlain & Chris Ellis] ): Diesel engine (~5000 vehicles)
* 3-inch Gun Motor Carriage M10A1: M4A3 chassis, Ford GAA gasoline engine (~1700 vehicles)
* 17pdr SP Achilles: M10 equipped with an Ordnance QF 17 pounder Mark V gun as used on the Sherman Firefly and British tanks. They can be identified by the muzzle brake at the end of the barrel and a counterweight behind the muzzle brake.
** Diesel-engined M10 became 17pdr SP Achilles IC,
** Petrol-engined M10A1 became 17pdr SP Achilles IIC
* Full-Track Prime Mover M35: Turretless M10A1 used as an artillery tractor
* 3in SP Wolverine: Proposed Canadian-built version using a Ram tank chassis — a single prototype was built in 1942. ["AFV News" Vol. 41, No. 2 May-Aug 2006]

* SP = "Self-Propelled"

Notes

The post-war American film star Audie Murphy won his Medal of Honor at the Battle of the Colmar Pocket when he used the heavy machine gun of an abandoned and burning M10 to repel German infantry despite the vehicle taking several more hits from tanks or artillery.

References

External links

* [http://afvdb.50megs.com/usa/3ingmcm10.html 3" Gun Motor Carriage M10 - AFV Database]
* [http://www.wwiivehicles.com/usa/tank-destroyers/m10.asp M10 3" Gun Motor Carriage - WWII Vehicles]
* [http://www.2iemeguerre.com/blindes/m35primemover.htm M35 Prime Mover - 2iemeguerre.com]