The M107, along with the M110, formed a pair of nearly identical self-propelled guns introduced in the early 1960s, essentially the heavy counterparts to the medium-caliber M108 and M109 which also entered service at the same time. They were designed to replace the M55 which was the largest calber SPG used by the US at the time. The M107 shared the same chassis as the M110, these featuring an all-welded aluminum hull with the driver seated at the front left and the turbocharged diesel engine to their right. A large spade was fitted in the rear of the hull and there were additional mechanisms fitted to the road wheels to improve stability when firing. Armament consisted of a 175-mm M113 gun on an open mount, which could fire to a maximum range of 32.8 km at a rate of two rounds per minute. Despite being of smaller caliber than the 203-mm gun of the M110, the barrel of the M107 was significantly longer which gave it nearly double the range. However, the lack of storage space meant that the M110 could only carry two rounds, necessitating the use of a M548 tracked cargo carrier at all times. The M110 was not fitted with defensive armament or NBC protection, and also lacked amphibious capability but it was air-transportable in a C-5. However, later versions were fitted with nylon or canvas covers which offered protection from the weather or also NBC conditions. The M107 was fielded in combat very effectively during the Vietnam War where it outranged most enemy artillery. It was also used by numerous NATO allies including Germany, Greece, Italy, Netherlands, Turkey and the UK, as well as Israel, Iran, and South Korea. By the 1970s, however, the US Army decided to covert their existing units to M110s where they served until the mid-1990s.
Development took place concurrently with the M110, with the prototype designation being T235 before entering production as the M107. Only one major variant, the M107E1, was developed which corrected numerous faults in the original model and adding mechanical and electrical improvements. It also added a nylon or canvas cover for additional protection.
Design | M107 |
Type | Self-Propelled Gun |
Year | 1962 |
Crew | 5 |
Dimensions | |
Length (w/Gun) | 5.72 m (11.26 m) |
Width | 3.149 m |
Height | 2.809 m |
Ground Clearance | 0.466 m |
Track | 2.692 m |
Track Width | 457 mm |
Track on Ground | 3.936 m |
Weight | |
Combat | 28,168 kg |
Empty | 25,915 kg |
Ground Pressure | 0.81 kg/cm² |
Suspension | Torsion bar |
Performance | |
Speed (Off-Road) | 56 km/h |
Range (Off-Road) | 725 km |
Amphibious | No |
Fording | 1.07 m |
Vertical Obstacle | 1.02 m |
Trench | 2.36 m |
Gradient | 60% |
Side Slope | 30% |
Powerplant | |
Engine | 1 x 405-hp Detroit Diesel 8V-71T |
Fuel | Diesel: 1,137 L |
Power/Weight | 14.38 hp/t |
Armament | |
Main | 1 x 175-mm L/60M113Field Gun↑ 65° / ↓ -2° / ↔ 60° |
Secondary | None |
Ammo | 175-mm: 2 |
Armor | |
Type | Steel |
Thickness | - |
Max Effective | - |
Production | |
Built | n/a |
Total | 0 |