Museum of the American G.I in College Station, Texas - Image of M4A1 Mortar Carrier Half Track

WWII M4A1 Mortar Carrier Halftrack

Year: 1943
Number Produced: over 600
Crew: 8
Main Armament: 81 mm M1 Mortar
Other Armament: .50 cal Machine Gun
.45 Submachine Gun
Engine: White 160AX
Horsepower: 147
Speed: 45 mph (72 km/h)
Weight: 9 tons
Length: 20’3” (6.18 m)
Width: 6’5” (1.96 m)
Height: 7’5” (2.27 m)

The M4A1 Mortar Carrier Halftrack, like the M3 Gun Motor Carriage, is a rare derivative of the original M2 Halftrack. The M4 version was developed to meet the need for a self-propelled artillery piece that could be unloaded at the battlefield. Most crews in practice rarely unloaded the gun, instead firing it while in its rear-facing position The M4A1 turned the gun around and reinforced the vehicle, allowing for more convenient firing. Originally an interim vehicle, it was only produced for 5 months, but it performed so well in the field that it made its intended replacement redundant.