The M115 203 mm howitzer, also known as the M115 8-inch Howitzer, and originally the M1 8-inch Howitzer was a towed heavy
howitzer
A howitzer () is a long- ranged weapon, falling between a cannon (also known as an artillery gun in the United States), which fires shells at flat trajectories, and a mortar, which fires at high angles of ascent and descent. Howitzers, like ot ...
developed and used by the
United States Army during World War II, the Korean War, and the Vietnam War.
History
During
World War I, licensed production of the
British 8-inch howitzer Mark VI was undertaken by the Midvale Steel and Ordnance Company, located in the
Nicetown neighborhood of
Philadelphia,
Pennsylvania. Both American and British-manufactured weapons were used by the
American Expeditionary Force
The American Expeditionary Forces (A. E. F.) was a formation of the United States Army on the Western Front of World War I. The A. E. F. was established on July 5, 1917, in France under the command of General John J. Pershing. It fought alon ...
in France. In 1940, the United States still had 475 Mark VII and Mark VIII 1/2 howitzers in storage, but there are no reports of the Mark VI or other marks being used during World War II.
The original design of the M1 8-inch howitzer started in 1919, and resulted in the M1920 howitzer, but the program lapsed until resurrected in 1927. The T2 and T3 howitzers were prototypes of a partner piece for a new 155 mm gun. The first publicity photographs of the M1-type 8-inch howitzer on its redesigned carriage appeared in 1931, but development was slowed by the Great Depression. The T3 was standardized as the 8 inch Howitzer M1 in 1940.
Like the British 8-inch howitzer of the First World War (and most other large artillery), the M1 uses a
Welin screw for its breech. The carriage was the same as used for the US
155 mm gun and was also adopted by the British for their
BL 7.2-inch howitzer. It consists of a split trail with equilibrator assemblies, elevating and traversing mechanisms, a two-axle bogie with eight tires, and a single-axle, single-wheel limber for towing. Four spades, carried on the trails, were used to emplace the weapon.
The M1 saw U.S. service in World War II, the
Korean War, and the
Vietnam War. During World War II, the M1 was towed by the Mack 7⅓ ton 6×6 truck or the
M4 tractor. 59 battalions were raised during the war, of which 39 saw combat service in Northwest Europe or Italy and three in the Pacific.
In the late 1950s, it was adopted in small numbers by several
NATO armies, to fire the
W33 (M422/M422A1 shell) and later the
W79 nuclear artillery shell, under the NATO
nuclear sharing concept, a role which ended when the smallest types of
tactical nuclear weapons were removed from service and eliminated. It was also adopted as a field weapon by a number of nations in Europe, the Middle East, and Asia and saw service in the
Second Taiwan Strait Crisis and the
Croatian War of Independence
The Croatian War of Independence was fought from 1991 to 1995 between Croat forces loyal to the Government of Croatia—which had declared independence from the Socialist Federal Republic of Yugoslavia (SFRY)—and the Serb-controlled Yugosl ...
. In 1962, the M1 was redesignated the M115 Howitzer.
Operators
* : former operator
* : former operator, 14 systems in 1983
* : former operator, 24 systems
* : former operator
1953–1996, 12 systems
* : former operator
* : former operator
* :
* : 20
*
* : 4 in store
* : former operator
* : The
Armed Forces
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...
acquired right after the
Korean War in 1953. Began replacing in the late 2000s with the K9 Thunder.
*
* : 28
* : 8 in store
* : former operator
* : in Turkey, 60 systems
* : 70
* : 162
Self-propelling mounts

* The howitzer was mounted on a modified
M4 medium tank
}
The M4 Sherman, officially Medium Tank, M4, was the most widely used medium tank by the United States and Western Allies in World War II. The M4 Sherman proved to be reliable, relatively cheap to produce, and available in great numbers. It w ...
chassis, in mount M17. The resulting vehicle was initially designated 8 inch Howitzer Motor Carriage T89 and eventually standardized as the
8 inch Howitzer Motor Carriage M43. A total of 48 units were built.
[Hunnicutt - ''Sherman: A History of the American Medium Tank'', pp. 353–355, 571.]
* 8 inch Howitzer Motor Carriage T80 – based on
T23 Medium Tank chassis, never advanced past proposal stage.
[Hunnicutt - ''Pershing, A History of the Medium Tank T20 Series'', p. 158.]
* 8 inch Howitzer Motor Carriage T84 – based on
T26 Medium Tank chassis, a single pilot was built in 1945.
[Hunnicutt - ''Pershing, A History of the Medium Tank T20 Series'', p. 159.]
* The howitzer was mounted on a purpose-built tracked chassis to become the
8 inch Self-Propelled Howitzer M110. Notably, accuracy and rate of fire suffered from having to depress the cannon tube to loading elevation for each round in order to use the track-mounted auto loader, But the later M110A2 version had improved accuracy and ranges.
Ammunition
The howitzer fired separate loading,
bagged charge ammunition, with seven different propelling charges, from 1 (the smallest) to 7 (the largest).
See also
*
8-inch gun M1
*
203 mm howitzer M1931 (B-4)
203 mm howitzer M1931 (B-4) (russian: 203-мм гаубица обр. 1931 г. (Б-4), GRAU index 52-G-625) was a 203 mm (8 inch) Soviet high-power heavy howitzer. During the Second World War, it was under the command of the Stavk ...
—approximate Soviet equivalent
*
BL 7.2-inch howitzer—British equivalent
*
List of U.S. Army weapons by supply catalog designation—SNL D-29
Notes
References
*
*
*
*
*
Missing Lynx* TM 9-2300 Standard Artillery and fire Control Material (dated Feb. 1944)
* TM 9-335
* TM 9-1350
External links
*
{{WWIIUSGuns
203 mm artillery
Cold War artillery of the United States
World War II artillery of the United States
World War II field artillery
World War II howitzers
Military equipment introduced in the 1930s