World War II Database

Contributor: Alan Chanter

ww2dbaseThis was the first American self-propelled weapon to be used in combat during the Second World War.

ww2dbaseIn June 1941 the Aberdeen Proving Ground in Maryland, United States was requested to adapt the 75mm field gun to a half track carriage in order to provide a suitable mobile weapon for the tank destroyer battalions at that time being contemplated. The M1897A4 gun (originally a French design) was fitted, on a pedestal mount with a protective shield, into the cargo space of a standard White M2 armoured personnel carrier, where it had a traverse of 19 degrees left and 21 degrees to the right. It was fired forward over the cab and the projectile had a muzzle velocity of 2,000 feet per second.

ww2dbaseThe vehicle was standardized as the GMC M3 in November 1941, by which time a small number had been sent to the Philippine Islands where they proved effective, shortly afterwards, in dealing with Japanese tanks during the invasion. Others were used in action in Tunisia and Italy, where they did rather less well against German armour. The fundamental defect was that the gun, dated from 1897, and was no longer sufficient to cope with modern armour. The GMC M3 was reclassified in March 1944 and declared obsolete in September.

ww2dbaseThey were also used by the US Marine Corps in the Pacific theatre, equipping both Special Weapons Battalions and Regimental Weapons Companies from mid-1944, but began to be replaced by the 105mm self-propelled guns towards the closing weeks of that year. The Marines employed it principally as an assault gun for knocking out fortifications and for indirect artillery fire. In the USMC the type was commonly known as the SPM (Self Propelled Mount). In addition a number were supplied to the British where they were used in Armoured Car regiments for fire support purposes.

SPECIFICATIONS

M3 Gun Motor Carriage

Machinery	6,326cc White 160AX 6-cylinder petrol engine rated at 128bhp at 2800rpm
Suspension	Semi-elliptic volute spring
Armament	1x75mm M1897A4 gun (59 rounds)
Armor	6-12mm
Crew	5
Length	6.23 m
Width	2.15 m
Height	2.50 m
Weight	9.1 t
Speed	72 km/h
Range	320 km

Photographs