The 3 inch Gun Motor Carriage M10 design was standardised in June 1942 and production begun in September. It was based on the chassis of the Sherman Tank with the M7 3 inch gun being carried in an open topped turret with full 360° traverse. There were two variants, the M10 with a diesel engine and the M10A1 with a petrol engine. It saw service in Italy and North West Europe especially with the Canadian and Polish anti-tank units. The 3 inch Gun was replaced bit by bit with the British 17 pounder anti-tank gun.
Gun 3 inch M7
Data
| Length of Bore | 150 inches (50 calibres) |
| Rifling | 28 grooves, uniform Right Hand 1/40 |
| Breech Mechanism | Vertical sliding block, semi-automatic, percussion fired |
| Traverse | 360° |
Performance
Firing AP Shot M79
| Muzzle Velocity | 2,600 feet per second |
| Maximum Range | 12,770 yards |
| Penetration at 2,000 yards/30° | 2.5 inches (64 mm) |
Firing APC/BC HE-T Shell M62
| Muzzle Velocity | 2,600 feet per second |
| Maximum Range | 16,100 yards |
| Penetration at 2,000 yards/30° | 1.7 inches (76 mm) |
Firing HE Shell M42
| Muzzle Velocity | 2,800 feet per second |
| Maximum Range | 14,780 yards |
HVAP Shot M93
| Muzzle Velocity | 3,400 feet per second |
| Maximum Range | 13,100 yards |
| Penetration at 2,000 yards/30° | 3.9 inches (98 mm) |
Carriage M10
Data
| Height | 114 inches over AA machinegun |
| Width | 120 inches |
| Length | 235.1 inches without gun |
| Weight Loaded | 65,200 lbs |
| Maximum Speed | 30 mph (48 km/h) on road |
| Range M10 M10A1 | 200 miles (320 km) 160 miles (260 km) |
Crew
| Commander |
| Layer |
| Loader |
| Driver |
| Co-Driver |