M15 half-track

M15 Combination Gun Motor Carriage
An M15A1 CGMC displayed at the Fort Lewis Military Museum
Type	Self-propelled anti-aircraft gun
Place of origin	United States
Service history
In service	1943–53
Used by	United States
Wars	World War II Korean War
Production history
Designer	United States Army
Designed	1940–42
Manufacturer	Autocar Company
Produced	1942–44
No. built	2,332
Specifications
Mass	10 short tons (9.1 t)
Length	20 ft 3 in (6.17 m)
Width	7 ft 4 in (2.24 m)
Height	7 ft 10 in (2.39 m)
Crew	7
Armor	0–12 mm (0.00–0.47 in)
Main armament	M1 37 mm (1.5 in) gun with 2 × .50 cal (12.7 mm (0.50 in)) M2 Browning machine guns
Engine	White 160AX, 386 in3 (6,330 cc) 6-cylinder, gasoline, compression ratio 6.3:1 128 hp (95 kW)
Power/weight	15.8 hp/ton
Suspension	Half-track, vertical volute springs; front leaf spring
Fuel capacity	60 US gal (230 L)
Operational range	150 mi (240 km)
Maximum speed	41.9 mph (67.4 km/h)

The M15 half-track, officially designated M15 Combination Gun Motor Carriage, was a self-propelled anti-aircraft gun on a half-track chassis used by the United States Army during World War II. It was equipped with one 37 millimeter (1.5 in) M1 autocannon and two water-cooled .50 caliber (12.7 mm) M2 Browning heavy machine guns.^[1] Based on the M3 half-track chassis, it was produced by the Autocar Company between July 1942 and February 1944, and served alongside the M16 Multiple Gun Motor Carriage.^[1]

The M15 evolved from the T28 project, an outgrowth of a 37 millimeter (1.5 in) gun mounted on an M2 half-track. Initially designated as the T28E1 Combination Gun Motor Carriage (CGMC), it was modified and accepted into service in 1943 as the M15.^[1] While conceived as an anti-aircraft weapon, its 37 mm gun was often used as an infantry support weapon during the later stages of World War II. The M15A1 was an improved variant with air-cooled machine guns mounted below the 37 mm gun. The M15 "Special" was an M15 armed with a single Bofors 40 mm gun.

During World War II, the vehicle served the U.S. Army throughout the Mediterranean, European, and Pacific theaters of operations. In the Korean War, the M15 served alongside the M16 providing infantry support.