M107 (projectile)
Encyclopedia
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
and US Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
' standard high explosive (HE) projectile
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...
for howitzer
Howitzer
A howitzer is a type of artillery piece characterized by a relatively short barrel and the use of comparatively small propellant charges to propel projectiles at relatively high trajectories, with a steep angle of descent...
s. It is a bursting round with fragmentation and blast effects.
The M107 is being superseded in the US military by the M795 projectile.
Development
The M107 is a development of the M102 155 mm shell, that was developed in the 1930s from the FrenchFrance
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
Schneider 155 mm projectile for the Model 1917 Howitzer. The M107 differs from the M102 mainly in having a wider driving band
Driving band
The driving band or rotating band is part of an artillery shell, a band of soft metal near the middle of the shell, typically made of gilding metal, copper or lead...
.
The shell was modified in 1944 to accommodate VT fuzes
Proximity fuze
A proximity fuze is a fuze that is designed to detonate an explosive device automatically when the distance to target becomes smaller than a predetermined value or when the target passes through a given plane...
. This involved adding a deep drilled cavity below the fuze well. Since most VT fuze
Fuze
Fuze Beverage, commercially referred to as just Fuze , is a manufacturer of teas and non-carbonated fruit drinks enriched with vitamins. Currently the brand consists of five vitamin-infused lines: Slenderize, Refresh, Tea, Defensify, and Vitalize...
s now do not require such a cavity (because they use smaller and fewer electronic components) a small aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
-wrapped 136 g TNT supplemental charge is fitted in the space.
Description
The body consists of a hollow steelSteel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
shell containing high explosive (either TNT or Composition B
Composition B
Composition B, colloquially "comp B", is an explosive consisting of castable mixtures of RDX and TNT. It is used as the main explosive filling in artillery projectiles, rockets, land mines, hand grenades, sticky bombs and various other munitions...
) painted olive drab with yellow markings. A fuze
Fuze
Fuze Beverage, commercially referred to as just Fuze , is a manufacturer of teas and non-carbonated fruit drinks enriched with vitamins. Currently the brand consists of five vitamin-infused lines: Slenderize, Refresh, Tea, Defensify, and Vitalize...
adapter is screwed into the body and brazed in place. An eyebolt lifting plug is screwed into the fuze well to assist in transportation. The plug is removed and replaced with a fuze for firing. The complete projectile weighs 43.2 kg, is 800 mm long and contains 15.8% explosive by weight. It is a separate-loading projectile - propellant
Propellant
A propellant is a material that produces pressurized gas that:* can be directed through a nozzle, thereby producing thrust ;...
bags or MAC charges are loaded separately.
On detonation it produces approximately 1,950 fragments.
The M107 was approved for use in 1958 and issued to the army from 1959. Its intended replacement is the M795, manufacture of which began in 1999.
The M114 howitzer can fire an M107 up to 14.5 km using M4A2 "White Bag" propellant; maximum range is 18.1 km. Modified M107 rounds with base bleed
Base bleed
Base bleed is a system used on some artillery shells to increase their range, typically by about 30%.Most of the drag on an artillery shell comes from the nose of the shell, as it pushes the air out of its way at supersonic speeds. Shaping the shell properly can reduce this greatly. However,...
and new aerodynamics can extend this range to around 32 km.
Despite relatively lackluster performance (Jane's describes it as having "an indifferent charge to weight ratio", "unsophisticated aerodynamic shape", "erratic fragmentation") compared to more modern high explosive rounds, it continues to be used by many countries, in particular in training exercises because of its low cost, high availability and smaller danger area than more modern designs. Its limited effectiveness also make it a useful option in peace support operations.
M107 is manufactured by several nations, sometimes with variations in the fill and or filling method, or other details, and is given a national designation. For example those produced to UK requirements are designated L21 not M107; German examples were designated DM21.
Specifications
- Weight as fired: 43.88 kg
- Explosive content:
- Composition B: 6.985 kg plus 0.136 kg TNT supplemental charge.
- TNT: 6.62 kg plus 0.136 kg TNT supplemental charge.
- Length (excluding fuze): 605.3 mm
- Body diameter: 154.89 mm
- Driving band diameter: 157.98 mm
- FuzeFuzeFuze Beverage, commercially referred to as just Fuze , is a manufacturer of teas and non-carbonated fruit drinks enriched with vitamins. Currently the brand consists of five vitamin-infused lines: Slenderize, Refresh, Tea, Defensify, and Vitalize...
s (with supplemental charge):- PD M51A5, M728 family, M557, M572, M739, M564, M577, M582, M732
- FuzeFuzeFuze Beverage, commercially referred to as just Fuze , is a manufacturer of teas and non-carbonated fruit drinks enriched with vitamins. Currently the brand consists of five vitamin-infused lines: Slenderize, Refresh, Tea, Defensify, and Vitalize...
s (without supplemental charge):- M728
- Manufacturer: American Ordnance LLC & Scranton Army Ammunition Plant