4.5 inch Gun M1
Encyclopedia
The 4.5 inch Gun M1 was a field gun developed in the United States
in the beginning of World War II
. It shared the same carriage with the 155mm Howitzer M1
and fired the same ammunition as the British
BL 4.5 inch Medium Field Gun
. The weapon was used by the US Army in Northwest Europe late in the war for corps
support; with the end of hostilities it was declared obsolete.
, this caliber was also selected for the new weapon. The development resulted in 4.7 inch Gun M1922E on Carriage M1921E. Due to lack of funding, the design never reached production.
In 1939 the program was restarted; the renewed design, designated 4.7 inch Gun T3, was ready by early 1940; it utilized the same carriage as the concurrently developed 155 mm howitzer
. At this stage, the army decided to change the weapon to use the British
4.5 inch ammunition. The modified gun was standardized in April 1941 as 4.5 inch Gun M1 on Carriage M1.
The production started in September 1942 and continued until February 1944.
of 4.5 inch (114 mm) caliber. The tube had uniform right hand twist, with one turn in 32 calibers. The unbalanced weight of the barrel was supported by two equilibrator springs. The breach was of interrupted screw
type; the recoil system hydropneumatic, variable length. The carriage was of split trail type, unsprung and had wheels with pneumatic tires. In firing position, the weapon was supported by a retractable pedestal. The gun was equipped with M12 panoramic sight.
The M1 equipped 16 or 17 field artillery battalions in the Northwest Europe
, where it was employed for corps
support. M5 High Speed Tractor
was assigned as prime mover
. The weapon was declared obsolete in September 1945.
The gun had good range, nearly five km longer than its 155 mm howitzer sibling and longer than the 155 mm Gun M1918MI
. It was out-ranged by another 155 mm gun, the Long Tom
, but the latter was nearly three times heavier.
On the other side, the 4.5 inch gun was criticized for insufficient power of its high explosive shell. The shell was produced from low grade ("19 ton") steel, which necessitated thick walls. As a result, it carried only about two kg of TNT or substitute, in fact less than the 105 mm high explosive shell. Additionally, it was felt that having a small number of guns of atypical caliber unnecessarily complicated logistics.
The weapon was experimentally mounted on a lengthened chassis of the M5 light tank
, in mount M1. The resulting vehicle received the designation 4.5in Gun Motor Carriage T16. A single prototype was built.
The projectile could be fired with propelling charge M7 (normal) at reduced velocity or with propelling charge M8 (super) to achieve full velocity. The dummy propelling charge M6 simulated the M8 charge. The velocity and range data in the table below is for the M8 charge.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
in the beginning of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. It shared the same carriage with the 155mm Howitzer M1
M114 155 mm howitzer
The M114 155 mm howitzer was a towed howitzer used by the United States Army. It was first produced in 1942 as a medium artillery piece under the designation of 155 mm Howitzer M1. It saw service with the US Army during World War II, the Korean War, and the Vietnam War, before being...
and fired the same ammunition as the British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
BL 4.5 inch Medium Field Gun
BL 4.5 inch Medium Field Gun
The BL 4.5 inch Medium Gun was a British gun used by field artillery in the Second World War. It had nothing in common with the QF 4.5 inch Howitzer or the QF 4.5 inch AA Gun.- History :...
. The weapon was used by the US Army in Northwest Europe late in the war for corps
Corps
A corps is either a large formation, or an administrative grouping of troops within an armed force with a common function such as Artillery or Signals representing an arm of service...
support; with the end of hostilities it was declared obsolete.
Development and production
In 1920 the US Army Ordnance started to work on a new medium field gun. Since the US Army had already employed the 4.7 inch Gun Model 1906 during World War IWorld War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
, this caliber was also selected for the new weapon. The development resulted in 4.7 inch Gun M1922E on Carriage M1921E. Due to lack of funding, the design never reached production.
In 1939 the program was restarted; the renewed design, designated 4.7 inch Gun T3, was ready by early 1940; it utilized the same carriage as the concurrently developed 155 mm howitzer
M114 155 mm howitzer
The M114 155 mm howitzer was a towed howitzer used by the United States Army. It was first produced in 1942 as a medium artillery piece under the designation of 155 mm Howitzer M1. It saw service with the US Army during World War II, the Korean War, and the Vietnam War, before being...
. At this stage, the army decided to change the weapon to use the British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
4.5 inch ammunition. The modified gun was standardized in April 1941 as 4.5 inch Gun M1 on Carriage M1.
The production started in September 1942 and continued until February 1944.
| Production of M1 | |||||||||||
| Year | 1942 | 1943 | 1944 | Total | |||||||
| Produced, pcs. | 41 | 345 | 40 | 416 | |||||||
Description
The M1 was very similar in construction and appearance to the 155mm Howitzer M1. The only significant difference was its tubeGun barrel
A gun barrel is the tube, usually metal, through which a controlled explosion or rapid expansion of gases are released in order to propel a projectile out of the end at a high velocity....
of 4.5 inch (114 mm) caliber. The tube had uniform right hand twist, with one turn in 32 calibers. The unbalanced weight of the barrel was supported by two equilibrator springs. The breach was of interrupted screw
Interrupted screw
An interrupted screw or interrupted thread is a mechanical device typically used in the breech of artillery guns. It was invented circa 1845....
type; the recoil system hydropneumatic, variable length. The carriage was of split trail type, unsprung and had wheels with pneumatic tires. In firing position, the weapon was supported by a retractable pedestal. The gun was equipped with M12 panoramic sight.
Service
Western Front (World War II)
The Western Front of the European Theatre of World War II encompassed, Denmark, Norway, Luxembourg, Belgium, the Netherlands, France, and West Germany. The Western Front was marked by two phases of large-scale ground combat operations...
, where it was employed for corps
Corps
A corps is either a large formation, or an administrative grouping of troops within an armed force with a common function such as Artillery or Signals representing an arm of service...
support. M5 High Speed Tractor
M5 Tractor
The M5 High-Speed Tractor was an artillery tractor used by the US Army from 1942.-Construction:The M5 is a fully track vehicle designed to tow the 105 mm Howitzer M2, and the 155 mm Long Tom field artillery, and carry the gun crew and ammunition. A winch and roller system allows the M5 to pull...
was assigned as prime mover
Artillery tractor
Artillery tractor is a kind of tractor, also referred to as a gun tractor, a vehicle used to tow artillery pieces of varying weights.-Traction:...
. The weapon was declared obsolete in September 1945.
The gun had good range, nearly five km longer than its 155 mm howitzer sibling and longer than the 155 mm Gun M1918MI
Canon de 155mm GPF
The Canon de 155 Grande Puissance Filloux mle.1917 was a 155 mm cannon used by the French Army during the first half of the 20th century.-History:The gun was designed during World War I by Colonel L.J.F...
. It was out-ranged by another 155 mm gun, the Long Tom
155 mm Long Tom
The 155 mm Gun M1 and M2 , widely known as Long Tom, were 155 millimeter calibre field guns used by the United States armed forces during World War II and Korean War. The Long Tom replaced the Canon de 155 mm GPF in United States service.-Development:Before entering World War I, the United...
, but the latter was nearly three times heavier.
On the other side, the 4.5 inch gun was criticized for insufficient power of its high explosive shell. The shell was produced from low grade ("19 ton") steel, which necessitated thick walls. As a result, it carried only about two kg of TNT or substitute, in fact less than the 105 mm high explosive shell. Additionally, it was felt that having a small number of guns of atypical caliber unnecessarily complicated logistics.
Variants
- 4.7 inch Gun M1920 on Carriage M1920.
- 4.7 inch Gun M1922E on Carriage M1921E.
- 4.7 inch Gun T3 (1940).
- 4.5 inch Gun M1 on Carriage M1 (1941).
The weapon was experimentally mounted on a lengthened chassis of the M5 light tank
Stuart tank
The 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...
, in mount M1. The resulting vehicle received the designation 4.5in Gun Motor Carriage T16. A single prototype was built.
Ammunition
The M1 utilized separate loading, bagged charge ammunition. Only high explosive projectile was available.The projectile could be fired with propelling charge M7 (normal) at reduced velocity or with propelling charge M8 (super) to achieve full velocity. The dummy propelling charge M6 simulated the M8 charge. The velocity and range data in the table below is for the M8 charge.
| Available ammunition. | |||||
| Type | Model | Projectile weight, kg | Filler | Muzzle velocity, m/s | Range, m |
| HE | HE M65 Shell | 24.9 | TNT, 2.04 kg or Amatol Amatol Amatol is a highly explosive material made from a mixture of TNT and ammonium nitrate. Its name originates from the words ammonium and toluene... 50/50, 1.85 kg or Trimonite, 2.10 kg |
693 | 19,317 |
| Dummy | Dummy M8 Projectile | - | - | ||
| Propelling charges | ||
| Model | Weight, complete, kg | Components |
| M7 (normal) | 2.95 | Single section |
| M8 (super) | 5.08 | Base charge and increment |
| M6 (dummy) | 5.40 | Base charge and increment |
| Concrete penetration, mm | ||||
| Ammunition \ Distance, m | 0 | 914 | 4,572 | 9,144 |
| HE M65 Shell (meet angle 0°) | 1,158 | 1,067 | 640 | 366 |
| Different methods of measurement were used in different countries / periods. Therefore, direct comparison is often impossible. | ||||