thedrifter
05-19-05, 05:27 PM
May 23, 2005
The Lore of the Corps
M103 built to counter Soviets’ heavy tanks
By Keith A. Milks
Special to the Times
In the years following World War II, the Soviet Union fielded heavy tanks that seriously outclassed everything in the U.S. inventory at the time. To counter this threat, the United States produced its own heavy tank in 1957 that met with mixed results in the field.
The M103 lived up to its heavy designation, weighing in at nearly 63 tons. Built by the Detroit Tank Arsenal, about 300 rolled off the assembly line; eventually, 220 found their way to the Marine Corps. The M103 was more than 10 feet tall, 12 feet wide and 38 feet long from barrel tip to rear hull.
The vehicle was protected by rolled and cast homogeneous steel that ranged in thickness from 1 to 10 inches. Typical of tanks, the M103’s armor was thickest in the front of the hull and around the turret’s gun shield, while its least protected areas were the turret roof and rear.
Powered by a 12-cylinder gasoline engine, the M103 boasted a top road speed of 25 miles per hour and an 80-mile range. This sluggish performance was due in no small part to a critical design flaw: The M103 was powered by the same engine used to propel the M48, which was about 12 tons lighter.
The M103’s biggest punch came courtesy of an M58 120mm main gun, with a store of 34 rounds. In addition to the commander’s mounted .50-caliber machine gun, two .30-caliber machine guns were located coaxial with the main gun.
The 120mm round could defeat all known armored vehicles of the time. A commander, gunner, driver and two loaders were required to keep the main gun in action, however.
Seated in the rear of the turret, one loader would insert the projectile into the gun’s breech. The second loader would add the propellant cartridge.
This unusually large crew, an engine ill-suited to the tank’s size and a host of technical and performance problems forced a redesign.
Roughly 219 M103s were converted to the M103A1, which featured an improved targeting system and turret-mounted storage basket. The tank’s further upgrade to the M103A2 in 1964 saw the inferior engine replaced by a supercharged diesel that improved the overall performance, most notably increasing the tank’s range to 300 miles.
The Marine Corps fielded the M103 heavy tank within the third company of each tank battalion, with medium tanks serving in the other two. The M103’s weight and size made it ill-suited for amphibious operations, and the Corps’ M48 medium tanks bore the brunt of combat in Vietnam.
The M103-series heavy tanks were out of the Marine Corps inventory by 1974, replaced by the M60. That tank featured a 120mm gun and armor similar to that of the M103-series, but was 10 tons lighter.
With the departure of the M103, the designations light, medium and heavy were eliminated. Those terms were replaced by “main battle tank” in the military’s vernacular.
The writer is a gunnery sergeant stationed at Camp Lejeune, N.C. He can be reached at kambtp@aol.com.
Ellie
The Lore of the Corps
M103 built to counter Soviets’ heavy tanks
By Keith A. Milks
Special to the Times
In the years following World War II, the Soviet Union fielded heavy tanks that seriously outclassed everything in the U.S. inventory at the time. To counter this threat, the United States produced its own heavy tank in 1957 that met with mixed results in the field.
The M103 lived up to its heavy designation, weighing in at nearly 63 tons. Built by the Detroit Tank Arsenal, about 300 rolled off the assembly line; eventually, 220 found their way to the Marine Corps. The M103 was more than 10 feet tall, 12 feet wide and 38 feet long from barrel tip to rear hull.
The vehicle was protected by rolled and cast homogeneous steel that ranged in thickness from 1 to 10 inches. Typical of tanks, the M103’s armor was thickest in the front of the hull and around the turret’s gun shield, while its least protected areas were the turret roof and rear.
Powered by a 12-cylinder gasoline engine, the M103 boasted a top road speed of 25 miles per hour and an 80-mile range. This sluggish performance was due in no small part to a critical design flaw: The M103 was powered by the same engine used to propel the M48, which was about 12 tons lighter.
The M103’s biggest punch came courtesy of an M58 120mm main gun, with a store of 34 rounds. In addition to the commander’s mounted .50-caliber machine gun, two .30-caliber machine guns were located coaxial with the main gun.
The 120mm round could defeat all known armored vehicles of the time. A commander, gunner, driver and two loaders were required to keep the main gun in action, however.
Seated in the rear of the turret, one loader would insert the projectile into the gun’s breech. The second loader would add the propellant cartridge.
This unusually large crew, an engine ill-suited to the tank’s size and a host of technical and performance problems forced a redesign.
Roughly 219 M103s were converted to the M103A1, which featured an improved targeting system and turret-mounted storage basket. The tank’s further upgrade to the M103A2 in 1964 saw the inferior engine replaced by a supercharged diesel that improved the overall performance, most notably increasing the tank’s range to 300 miles.
The Marine Corps fielded the M103 heavy tank within the third company of each tank battalion, with medium tanks serving in the other two. The M103’s weight and size made it ill-suited for amphibious operations, and the Corps’ M48 medium tanks bore the brunt of combat in Vietnam.
The M103-series heavy tanks were out of the Marine Corps inventory by 1974, replaced by the M60. That tank featured a 120mm gun and armor similar to that of the M103-series, but was 10 tons lighter.
With the departure of the M103, the designations light, medium and heavy were eliminated. Those terms were replaced by “main battle tank” in the military’s vernacular.
The writer is a gunnery sergeant stationed at Camp Lejeune, N.C. He can be reached at kambtp@aol.com.
Ellie