M116 howitzer
Encyclopedia
The 75mm Pack Howitzer M1 (also known by its post-war designation M116) was designed in the United States in 1920s to meet a need for an artillery piece that could be moved across difficult terrain. The gun and carriage was designed so that it could be broken down into several pieces to be carried by pack animal
s. The gun saw combat in Second World War with the US Army (primarily used by airborne units), with US Marine Corps, and was also supplied to foreign forces.
In addition to the pack / air portable configuration, the gun was mounted on a non-dismantling carriage to serve as a field artillery piece. Derived vehicle mounted howitzers M2 and M3 were used in the 75mm HMC M8 and some LVT
models. In addition, the M1 in its original version was mated to a number of other self-propelled carriages, though only one of those – 75mm HMC T30
– reached mass production.
The only significant changes during the mass production period were carriage improvements. The original carriage M1 was of box trail type, with wooden wheels. Requirement for a lightweight howitzer for airborne troops led to introduction of the M8 carriage, similar except new wheels with pneumatic tires. Another requirement, from the cavalry branch of the US Army, resulted in a completely different family of "field howitzer" split trail
carriages M3A1 / M3A2 / M3A3. However, only limited number of the M1 in field howitzer variant were built, due to cavalry's switch to self-propelled guns.
M1 or M1A1 consisted of tube and breech
, which were joined together by interrupted threads, allowing for quick assembly and disassembly. One eighth of a turn was required to connect or disconnect tube and breech. The tube had uniform, right hand rifling with one turn in 20 calibers. The breech was of horizontal sliding block type, with continuous-pull firing mechanism.
The recoil
system was hydropneumatic. Both recoil buffer and recuperator were located under the barrel.
The pack howitzer carriage M1 had dismantling construction. The carriage was of box trail type, with steel-rimmed wooden wheels. For transportation, the howitzer M1 or M1A1 on carriage M1 could be broken down into six mule loads, with payload weight between 73 and 107 kg each:
The carriage M8 was identical, except for axle arms and wheels, which were metal with pneumatic tires. The howitzer on carriage M8 could be broken down into seven mule loads or into nine parachute loads (the latter arrangement included 18 rounds of ammunition). It could also be towed by vehicle such as 1/4 ton jeep
, or transported by plane or glider such as CG-4 Waco.
The field howitzer carriages of the M3 family were non-dismantling, split trail. All these were fitted with metal wheels with pneumatic tires; all had an additional retractable support, referred to as a firing base. In firing position, the firing base could be lowered and wheels raised, leaving the weapon to rest on the firing base and trails.
In the Second World War era US Army, 75 mm howitzers were issued to airborne
and mountain units.
An airborne division
, according to the organization of February 1944, had three 75 mm howitzer battalion
s – two glider
field artillery battalions (two six-gun batteries
each) and one parachute field artillery battalion (three four-gun batteries), in total 36 pieces per division. In December 1944, new Tables of Organization and Equipment increased the divisional firepower to 60 75 mm howitzers (as an option, in glider battalions 75 mm pieces could be replaced with more powerful 105mm M3).
The only mountain division formed, the 10th
, had three 75 mm howitzer battalions, 12 pieces each. The gun was also used by some separate field artillery
battalions.
In the US Marine Corps, under the E-series Tables of Organization (TO) from 15 April 1943 divisional artillery included three 75 mm howitzer battalions, 12 pieces each. The F-series TO from 5 May 1944 reduced the number of 75 mm battalions to two, and the G-series TO removed them altogether, completing the shift to 105 mm and 155 mm howitzers. Although the G-series TO was only adopted on 4 September 1945, in practice in some divisions the change was introduced early in 1945.
As of 2009, the M116 was still used by the US Army for ceremonial purposes
.
Two major lend lease recipients of the M1 were United Kingdom (826 pack howitzers) and China (637 pack howitzers and 125 field howitzers). 68 pieces were supplied to France, and 60 to various countries in Latin America.
In the British service, the howitzer was issued to two mountain artillery regiments, two airlanding light artillery regiments, raiding support regiment and was temporary used by some other units. The gun remained in British service until late 1950s.
The 75 mm howitzer was also used by Australian forces – two mountain batteries and some other units.
The experience of the guns given to the army of the Republic of China was particularly notable. After the loss of the mainland, the guns left behind were used both by the People's Liberation Army
and exported to the Viet Minh
. There is record of these guns being used at the Siege of Dien Bien Phu and, presumably, in later conflicts. The type by virtue of its compactness also remained in use with the ROCA
's outlying island garrisons as coastal artillery.
153 M116 were supplied to Japan (Japan Ground Self-Defense Force
) and they were used until 1980s .
As of 2010, the M116 75mm pack howitzer is still used by the Turkish Army in operations against the Kurdish separatist organization PKK in southeastern Turkey.
The howitzers have been used for avalanche
control at several western US ski areas.
In addition, M1 / M1A1 was mated to a number of other vehicles. Only the T30 reached mass production.
HEAT M66 Shell penetrated about 91 mm of homogeneous armor at 0 degrees at any range.
Pack animal
A pack animal or beast of burden is a working animal used by humans as means of transporting materials by attaching them so their weight bears on the animal's back; the term may be applied to either an individual animal or a species so employed...
s. The gun saw combat in Second World War with the US Army (primarily used by airborne units), with US Marine Corps, and was also supplied to foreign forces.
In addition to the pack / air portable configuration, the gun was mounted on a non-dismantling carriage to serve as a field artillery piece. Derived vehicle mounted howitzers M2 and M3 were used in the 75mm HMC M8 and some LVT
Landing Vehicle Tracked
The Landing Vehicle Tracked was a class of amphibious vehicles introduced by the United States Navy, Marine Corps and Army during World War II. Originally intended solely as cargo carriers for ship to shore operations, they rapidly evolved into assault troop and fire support vehicles as well...
models. In addition, the M1 in its original version was mated to a number of other self-propelled carriages, though only one of those – 75mm HMC T30
M3 Half-track
The Carrier, Personnel Half-track M3 was an armored vehicle used by the United States, the British Empire and the other Allies during World War II and the Cold War. Nearly 43,000 were produced, and supplied to the U.S...
– reached mass production.
Development and production
The 75 mm pack howitzer was designed in the United States in 1920s to meet a need for an artillery piece that could be moved across difficult terrain. In August 1927, the weapon was standardized as Howitzer, Pack, 75mm M1 on Carriage M1. Due to meager funding, production rates were low; by 1940, only 91 pieces were manufactured. Only in September 1940, a year into World War II, was the howitzer put into mass production. By then, M1 was succeeded by the slightly modified M1A1. The production continued until December 1944.The only significant changes during the mass production period were carriage improvements. The original carriage M1 was of box trail type, with wooden wheels. Requirement for a lightweight howitzer for airborne troops led to introduction of the M8 carriage, similar except new wheels with pneumatic tires. Another requirement, from the cavalry branch of the US Army, resulted in a completely different family of "field howitzer" split trail
Split trail
The split trail is a type of gun mount or gun carriage for relatively small and transportable artillery pieces....
carriages M3A1 / M3A2 / M3A3. However, only limited number of the M1 in field howitzer variant were built, due to cavalry's switch to self-propelled guns.
| Wartime production of М1, pcs. | |||||||||||
| Year | 1940 | 1941 | 1942 | 1943 | 1944 | Total | |||||
| Pack howitzers, pcs. | 36 | 188 | 1,280 | 2,592 | 915 | 4,939 | |||||
| Field howitzers, pcs. | – | 234 | 64 | 51 | – | 349 | |||||
Description
The howitzerHowitzer
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...
M1 or M1A1 consisted of tube and breech
Breechblock
A breechblock is the part of the firearm action that closes the breech of a weapon at the moment of firing....
, which were joined together by interrupted threads, allowing for quick assembly and disassembly. One eighth of a turn was required to connect or disconnect tube and breech. The tube had uniform, right hand rifling with one turn in 20 calibers. The breech was of horizontal sliding block type, with continuous-pull firing mechanism.
The recoil
Recoil
Recoil is the backward momentum of a gun when it is discharged. In technical terms, the recoil caused by the gun exactly balances the forward momentum of the projectile and exhaust gasses, according to Newton's third law...
system was hydropneumatic. Both recoil buffer and recuperator were located under the barrel.
The pack howitzer carriage M1 had dismantling construction. The carriage was of box trail type, with steel-rimmed wooden wheels. For transportation, the howitzer M1 or M1A1 on carriage M1 could be broken down into six mule loads, with payload weight between 73 and 107 kg each:
- Tube
- Breech and wheels
- Top sleigh and cradle
- Bottom sleigh and recoil mechanism
- Front trail
- Rear trail and axle.
The carriage M8 was identical, except for axle arms and wheels, which were metal with pneumatic tires. The howitzer on carriage M8 could be broken down into seven mule loads or into nine parachute loads (the latter arrangement included 18 rounds of ammunition). It could also be towed by vehicle such as 1/4 ton jeep
Willys MB
The Willys MB US Army Jeep and the Ford GPW, were manufactured from 1941 to 1945. These small four-wheel drive utility vehicles are considered the iconic World War II Jeep, and inspired many similar light utility vehicles. Over the years, the World War II Jeep later evolved into the "CJ" civilian...
, or transported by plane or glider such as CG-4 Waco.
The field howitzer carriages of the M3 family were non-dismantling, split trail. All these were fitted with metal wheels with pneumatic tires; all had an additional retractable support, referred to as a firing base. In firing position, the firing base could be lowered and wheels raised, leaving the weapon to rest on the firing base and trails.
US forces
Airborne forces
Airborne forces are military units, usually light infantry, set up to be moved by aircraft and 'dropped' into battle. Thus they can be placed behind enemy lines, and have an ability to deploy almost anywhere with little warning...
and mountain units.
An airborne division
Division (military)
A division is a large military unit or formation usually consisting of between 10,000 and 20,000 soldiers. In most armies, a division is composed of several regiments or brigades, and in turn several divisions typically make up a corps...
, according to the organization of February 1944, had three 75 mm howitzer battalion
Battalion
A battalion is a military unit of around 300–1,200 soldiers usually consisting of between two and seven companies and typically commanded by either a Lieutenant Colonel or a Colonel...
s – two glider
Military glider
Military gliders have been used by the military of various countries for carrying troops and heavy equipment to a combat zone, mainly during the Second World War. These engineless aircraft were towed into the air and most of the way to their target by military transport planes, e.g...
field artillery battalions (two six-gun batteries
Artillery battery
In military organizations, an artillery battery is a unit of guns, mortars, rockets or missiles so grouped in order to facilitate better battlefield communication and command and control, as well as to provide dispersion for its constituent gunnery crews and their systems...
each) and one parachute field artillery battalion (three four-gun batteries), in total 36 pieces per division. In December 1944, new Tables of Organization and Equipment increased the divisional firepower to 60 75 mm howitzers (as an option, in glider battalions 75 mm pieces could be replaced with more powerful 105mm M3).
The only mountain division formed, the 10th
10th Mountain Division
The 10th Mountain Division is a light infantry division of the United States Army based at Fort Drum, New York. It is a subordinate unit of the XVIII Airborne Corps and the only division-sized element of the U.S. Army to specialize in fighting under harsh terrain and weather conditions...
, had three 75 mm howitzer battalions, 12 pieces each. The gun was also used by some separate field artillery
Field artillery
Field artillery is a category of mobile artillery used to support armies in the field. These weapons are specialized for mobility, tactical proficiency, long range, short range and extremely long range target engagement....
battalions.
In the US Marine Corps, under the E-series Tables of Organization (TO) from 15 April 1943 divisional artillery included three 75 mm howitzer battalions, 12 pieces each. The F-series TO from 5 May 1944 reduced the number of 75 mm battalions to two, and the G-series TO removed them altogether, completing the shift to 105 mm and 155 mm howitzers. Although the G-series TO was only adopted on 4 September 1945, in practice in some divisions the change was introduced early in 1945.
As of 2009, the M116 was still used by the US Army for ceremonial purposes
Ceremony
A ceremony is an event of ritual significance, performed on a special occasion. The word may be of Etruscan origin.-Ceremonial occasions:A ceremony may mark a rite of passage in a human life, marking the significance of, for example:* birth...
.
Other operators
In the British service, the howitzer was issued to two mountain artillery regiments, two airlanding light artillery regiments, raiding support regiment and was temporary used by some other units. The gun remained in British service until late 1950s.
The 75 mm howitzer was also used by Australian forces – two mountain batteries and some other units.
The experience of the guns given to the army of the Republic of China was particularly notable. After the loss of the mainland, the guns left behind were used both by the People's Liberation Army
People's Liberation Army
The People's Liberation Army is the unified military organization of all land, sea, strategic missile and air forces of the People's Republic of China. The PLA was established on August 1, 1927 — celebrated annually as "PLA Day" — as the military arm of the Communist Party of China...
and exported to the Viet Minh
Viet Minh
Việt Minh was a national independence coalition formed at Pac Bo on May 19, 1941. The Việt Minh initially formed to seek independence for Vietnam from the French Empire. When the Japanese occupation began, the Việt Minh opposed Japan with support from the United States and the Republic of China...
. There is record of these guns being used at the Siege of Dien Bien Phu and, presumably, in later conflicts. The type by virtue of its compactness also remained in use with the ROCA
Republic of China Army
The ROC Army's current operational strength includes 3 armies, 5 corps. As of 2005, the Army's 35 brigades include 25 infantry brigades, 5 armoured brigades and 3 mechanized infantry brigades...
's outlying island garrisons as coastal artillery.
153 M116 were supplied to Japan (Japan Ground Self-Defense Force
Japan Ground Self-Defense Force
The , or JGSDF, is the army of Japan. The largest of the three services of the Japan Self-Defense Forces, the Ground Self-Defense Force operates under the command of the chief of the ground staff, based in the city of Ichigaya, Tokyo. The present chief of ground staff is General Yoshifumi Hibako...
) and they were used until 1980s .
As of 2010, the M116 75mm pack howitzer is still used by the Turkish Army in operations against the Kurdish separatist organization PKK in southeastern Turkey.
The howitzers have been used for avalanche
Avalanche
An avalanche is a sudden rapid flow of snow down a slope, occurring when either natural triggers or human activity causes a critical escalating transition from the slow equilibrium evolution of the snow pack. Typically occurring in mountainous terrain, an avalanche can mix air and water with the...
control at several western US ski areas.
Variants
- Howitzer variants:
- M1920, M1922A, M1922B, M1923B, M1923E1, M1923E2 – prototypes.
- M1 – the first standardized variant. Based on M1923E2 with minor changes.
- M1A1 – variant with modified breech block and breech ring.
- M2 – vehicle mounted variant. Tube and breech from M1A1 were used. In order to provide a cylindrical recoil surface, the tube was fitted with an external sleeve. 197 built.
- M3 – vehicle mounted variant; like M2 but with recoil surface as a part of the tube. The M2 and M3 barrels were interchangeable.
- M116 – post-war designation of the complete weapon.
- M120 – post-war designation for saluting howitzers
- Carriage variants:
- M1 – dismantling box trail carriage with wooden wheels.
- M2A1, T2, T2E1, T2E2, T2E3 – experimental carriages.
- M3A1 – split-trail carriage with firing base and pneumatic tires.
- M3A2 – M3A1 with shield added.
- M3A3 – M3A2 with different wheels and combat tires.
- M8 – M1 with new wheels with pneumatic tires.
| Selected variants | |||||
| M1A1 on carriage M1 | M1A1 on carriage M8 | M1A1 on carriage M3A3 | |||
| Carriage type | box trail | box trail | split trail | ||
| Wheels | wooden, with steel rims | steel, with pneumatic tires | steel, with pneumatic tires | ||
| Shield | – | – | + | ||
| Length, m | 3.68 | 3.94 | |||
| Width, m | 1.22 | 1.73 | |||
| Height, m | 0.94 | 1.18 | |||
| Weight, combat, kg | 576 | 653 | 1,009 | ||
| Weight, travel, kg | 667 | 653 | 1,043 | ||
| Elevation | +5° to +45° | +5° to +45° | +9° to +50° | ||
| Traverse | 6° | 6° | 45° | ||
| Transportation | 6 mule loads | 1/4 ton 4x4 truck, 7 mule loads, 9 parachute loads, plane or glider | 1/4 ton 4x4 truck | ||
Self-propelled mounts
Two nearly identical vehicle mounted variants – M2 and M3 – were developed based on tube and breech of the M1A1, for use in the 75mm Howitzer Motor Carriage T47 / M8. Both variants had a cylindlical "recoil surface" around the tube. In the M2, the surface was provided by use of a separately manufactured sleeve, while in the M3 it became an integral part of the barrel. M2 and M3 were fully interchangeable. These guns were mounted on the below armored vehicles:- 75mm Howitzer Motor Carriage T47 / M8 – M2 / M3 in mount M7.
- LVT(A)-4Landing Vehicle TrackedThe Landing Vehicle Tracked was a class of amphibious vehicles introduced by the United States Navy, Marine Corps and Army during World War II. Originally intended solely as cargo carriers for ship to shore operations, they rapidly evolved into assault troop and fire support vehicles as well...
– M3 in mount M7. - LVT(A)-5Landing Vehicle TrackedThe Landing Vehicle Tracked was a class of amphibious vehicles introduced by the United States Navy, Marine Corps and Army during World War II. Originally intended solely as cargo carriers for ship to shore operations, they rapidly evolved into assault troop and fire support vehicles as well...
– M3 in mount M12.
In addition, M1 / M1A1 was mated to a number of other vehicles. Only the T30 reached mass production.
- Medium Tank T5E2 – M1A1.
- Experimental mount on Holt light tractor.
- 75mm Howitzer Motor Carriage T1 (Tank development chassis T2).
- 75mm Howitzer Motor Carriage T3 (Combat Car M1 chassis).
- 75mm Howitzer Motor Carriage T17 (Combat Car M1E3 chassis).
- 75mm Howitzer Motor Carriage T18 (Light Tank M3Stuart tankThe M3 Stuart, formally Light Tank M3, was an American light tank of World War II and supplied to British and Commonwealth forces under lend-lease prior to the entry of the U.S. into the war—and used thereafter by U.S...
chassis) – M1A1. - 75mm Howitzer Motor Carriage T30M3 Half-trackThe Carrier, Personnel Half-track M3 was an armored vehicle used by the United States, the British Empire and the other Allies during World War II and the Cold War. Nearly 43,000 were produced, and supplied to the U.S...
– M1A1 in mount T10. - 75mm Howitzer Motor Carriage T41 (Light Tank M5Stuart tankThe M3 Stuart, formally Light Tank M3, was an American light tank of World War II and supplied to British and Commonwealth forces under lend-lease prior to the entry of the U.S. into the war—and used thereafter by U.S...
chassis).
Ammunition
The gun fired fixed (HEAT M66) and semi-fixed ammunition, fitted with 75mm Cartridge Case M5A1 (type II) and (type I) accordingly. The propellant charge of semi-fixed ammunition consisted of base charge and three increments, forming four different charges, from 1 (the smallest) to 4 (the largest).HEAT M66 Shell penetrated about 91 mm of homogeneous armor at 0 degrees at any range.
| Available ammunition. | |||||
| Type | Model | Weight, kg (round/projectile) | Filler | Muzzle velocity, m/s | Range, m |
| HE | HE M48 Shell | 8.27 / 6.62 | TNT, 676 g | 381 | 8,790 |
| HE | HE M41A1 Shell | 7.89 / 6.24 | TNT, 503 g | 381 | 8,820 |
| HEAT-T | HEAT M66 Shell | 7.39 / 5.94 | 305 | 6,400 | |
| Smoke | WP M64 Shell | 8.56 / 6.91 | White phosphorus White phosphorus (weapon) White phosphorus is a material made from a common allotrope of the chemical element phosphorus that is used in smoke, tracer, illumination and incendiary munitions. Other common names include WP, and the slang term "Willie Pete," which is dated from its use in Vietnam, and is still sometimes used... |
381 | 8,790 |
| Smoke | FS M64 Shell | 8.64 / 6.99 | Sulfur trioxide Sulfur trioxide Sulfur trioxide is the chemical compound with the formula SO3. In the gaseous form, this species is a significant pollutant, being the primary agent in acid rain. It is prepared on massive scales as a precursor to sulfuric acid.-Structure and bonding:Gaseous SO3 is a trigonal planar molecule of... in Chlorosulfonic acid |
381 | 8,790 |
| Chemical | H M64 Shell | 8.43 / 6.78 | Mustard gas Sulfur mustard The sulfur mustards, or sulphur mustards, commonly known as mustard gas, are a class of related cytotoxic, vesicant chemical warfare agents with the ability to form large blisters on exposed skin. Pure sulfur mustards are colorless, viscous liquids at room temperature... |
381 | 8,790 |
| Drill | Drill Cartridge M2A2 | – | – | ||
| Drill (simulates HE M48) | Drill Cartridge M19 | – | – | ||
| Blank | – | – | |||
See also
- List of U.S. Army weapons by supply catalog designation SNL C-20
- SCR-203SCR-203The SCR-203 was a U.S. Army radio transceiver used during World War II and designed to be mounted on an animal pack saddle.-Specifications:The SCR-203 was a low power, short range, portable command set designed to clamp onto a Phillips pack saddle for animal-pack transportation and operation. It...
pack radio - Artillery observerArtillery observerA military artillery observer or spotter is responsible for directing artillery fire and close air support onto enemy positions. Because artillery is an indirect fire weapon system, the guns are rarely in line-of-sight of their target, often located tens of miles away...
External links
- The Old Army Mules Takes Guns Where Wheels Don't Go May 1941 Popular SciencePopular SciencePopular Science is an American monthly magazine founded in 1872 carrying articles for the general reader on science and technology subjects. Popular Science has won over 58 awards, including the ASME awards for its journalistic excellence in both 2003 and 2004...
- "Airplane Moves Artillery 120 Miles In An Hour", June 1931, Popular Science air transport of early version of M116 Howitzer