T30 Howitzer Motor Carriage

T30 Howitzer Gun Motor Carriage
A sketch of the T30 Howitzer Motor Carriage
Type	Self-propelled artillery
Place of origin	United States
Service history
In service	1942–50s
Used by	United States France
Wars	World War II First Indochina War
Production history
Designer	Ordnance Department
Designed	1941
Manufacturer	White Motor Company
Produced	February-April 1942 November 1942
No. built	500
Specifications
Weight	10.3 short tons (9.3 t)
Length	20 ft 7 in (6.28 m)
Width	6 ft 5 in (1.96 m)
Height	8 ft 3 in (2.51 m)
Armor	Up to 0.375 in (9.5 mm)
Main armament	M1 Pack Howitzer
Engine	White 160AX, 386 in3 (6,330 cc), 6-cylinder, gasoline engine, compression ratio 6.3:1 147 hp (110 kW)
Power/weight	15.8 hp/ton
Suspension	Vertical volute springs for tracks, leaf springs for the wheels
Fuel capacity	60 US gal (230 l)
Speed	40 mph (64 km/h)

The T30 Howitzer Motor Carriage (HMC) was a United States Army self-propelled gun used in World War II. Its design was based on requirements for an assault gun issued by the Armored Force in 1941 and it was built as an interim solution until a fully tracked design was complete.

Produced by the White Motor Company, the vehicle was simply a 75 mm Pack Howitzer M1 mounted on a modified M3 Half-track. It was first used in combat in the North African Campaign in November 1942. It later served in Italy and France, and possibly in the Pacific. Some were later leased to French forces and the type was used as late as the First Indochina War in the 1950s.

Based on the M3 Half-track, the T30's specifications were similar to its parent vehicle. It was 20 ft 7 in (6.28 m) long, 6 ft 5 in (1.96 m) wide, 8 ft 3 in (2.51 m) and high, and weighed 10.3 short tons (9.3 t). The suspension consisted of vertical volute springs for the tracks and leaf springs for the wheels, while the vehicle had a fuel capacity of 60 US gallons (230 l). It had a range of 150 mi (240 km) and had a speed of 40 mph (64 km/h), and was powered by a White 160AX, 147 hp (110 kW), 386 in³ (6,330 cc), six-cylinder, gasoline engine, with a compression ratio of 6.3:1. It had a power-to-weight ratio of 15.8 hp/ton.

The T30's main armament was a short barreled 3.0 in (75 mm) pack howitzer. The 75 mm Pack Howitzer M1 as mounted could depress nine degrees, elevate 50 degrees, and traverse 22.5 degrees to each side. The vehicle had stowage for sixty rounds of 75 mm ammunition and, although it was not designed for anti-tank use, it had a high explosive anti-tank (HEAT) shell that could penetrate 3 in (76 mm) of armor. The gun shield had 0.375 in (9.5 mm) thick armor, designed to stop a .30 cal (7.62 mm) bullet from 250 yards (230 m) away.