Ordnance QF 6 pounder
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| Ordnance QF 6-pounder 7 cwt | |
|---|---|
| Image:QF-6-pounder-batey-haosef-1.jpg QF 6 pdr at Batey ha-Osef | |
| Type | anti-tank gun |
| Place of origin | United Kingdom |
| Service history | |
| In service | 1942-1960 |
| Used by | British Commonwealth |
| Wars | WW2 |
| Production history | |
| Designed | 1940 |
| Specifications | |
| Weight | 1,140 kg / 2,520 lb |
| Length | 2.82 m |
| Barrel length | Mk II, III: 43 calibres Mk IV, V and M1: 50 calibres |
| Crew | 6 |
| | |
| Shell | 57x441R |
| Calibre | 2.24 in (57 mm) |
| Breech | vertical block |
| Carriage | split trail |
| Traverse: | 90 degrees |
| Muzzle velocity | APDS round: 3,000 ft/s (900 m/s) |
| Maximum range | 5,000 yards (4,600 m) |
The Ordnance QF 6-pounder 7 cwt, or just "6 pdr", was a British 57 mm gun, their primary anti-tank gun during the middle of World War II, as well as the main armament for a number of tanks. It was first used in North Africa in April 1942, and quickly replaced the 2 pounder in most roles, allowing the 25 pounder to revert to its artillery role. The US Army also adopted the 6 pdr as their primary anti-tank gun under the designation 57 mm anti-tank gun M1.
Contents |
[edit] History
[edit] Development and service
Limitations of the existing 2 pounders were apparent even as the gun was first entering service, and an effort was started to replace it with a much more capable QF weapon starting as early as 1938. The 6 pounder gun design was complete by 1940, but the carriage design was not completed until 1941. Having an urgent need for anti-tank guns, the British continued production of the established 2 pounder rather than stop production. Instead they built a new production line, further delaying the 6 pounder's entry into service until May 1942.
The 6-pounder easily dealt with contemporary enemy tanks, but over the next year the Germans introduced much heavier designs into service, notably the Tiger I and Panther. The standard 6 pounder shot was insufficient against the front armour of these new designs, but it was still effective against them from other angles.
After entering service, the 6 pounder was given a performance boost (and greater service life) with the development of improved ammunition. The first to be supplied was a "core" design, the APCR shot. This was followed in 1944 by the "Armour-Piercing, Discarding Sabot" (APDS) shot that greatly improved the armour penetrating ability. An HE shell was produced so that it could be used against unarmoured targets as well.
Although the 6 pounder was kept at least somewhat competitive through the war, the Army nevertheless started development of a more powerful weapon in 1942. Their aim was to produce a gun with the same general dimensions and weight as the 6 pounder, but with improved performance. The first attempt was an 8 pdr of 59 calibre length, but this version proved too heavy to be used in the same role as the 6 pdr. A second attempt was made with a shorter 48 calibre barrel, but this proved to have only marginally better performance than the 6 pounder. The program was eventually cancelled in January 1943.
Instead the 6 pounder was followed into service by the next generation British anti-tank gun, the 17 pounder which came into use from February 1943. As a smaller and more manoeuvrable gun, the 6 pounder continued to be used by the British Army not only for the rest of the World War II, but also for some 20 years after the war.
A 57/42.6 mm squeeze bore adaptor was developed for the gun but was never adopted.
Tank gun versions were used in Crusader III, Cavalier, Centaur I and II, Cromwell I to III, Valentine VIII to X and Churchill III and IV.
[edit] US production and service
The idea of manfacturing the 6 pounder in the US was expressed by the US Army Ordnance in February 1941. At that time the US Army still favoured the 37mm Gun M3 and production was planned solely for lend lease. The US version, classified as substitute standard under the designation "57mm Gun M1 on Carriage M1", was based on the 6 pounder Mk II, two units of which were received from the UK, but unlike the Mk II had the original long barrel. Production started early in 1942.
| М1 production, pcs. | |||||||||||
| Year | 1942 | 1943 | 1944 | 1945 | Total | ||||||
| Produced, pcs. | 3,877 | 5,856 | 3,902 | 2,002 | 15,637 | ||||||
It was only in spring 1943, following the experience of the North African Campaign, that the Infantry branch of the US Army reconciled itself with the need to field a heavier antitank gun than the 37mm M3. According to the Table of Organization and equipment from 26 May 1943, a regimental antitank company included nine 57mm guns and each battalion had an antitank platoon with three guns giving a total of 18 guns per regiment. Dodge WC-62 / WC-63 6x6 1 1/2 ton trucks were issued as prime movers. By mid-1944 the M1 was the standard antitank gun of the US infantry in the Western Front and outnumbered the M3 in Italy.
Due to the unexpected adoption for service, the only ammunition type in production in the US by mid-1943 was the AP round. Only after the Normandy Campaign did the HE round reach the battlefield, and the canister shot was not seen in significant numbers until the end of the war.
Like the British Army, the US Army also experimented with a squeeze bore adaptor (57/40mm T10), but the program was abandoned.
The gun went out of service in the US soon after the end of the war.
In addition to being used by the US Army, the M1 was supplied under the lend lease program to the United Kingdom (4,242 pieces), Free French Forces (653), USSR (400) and Brazil (57).
[edit] Variants
- Mk 2 - first mass production version. Shortened L/43 barrel was adopted due to the shortage of suitable manufacturing equipment.
- Mk 3 - tank version of Mk 2
- Mk 4 - L/50 barrel, single baffle muzzle brake.
- Mk 5 - tank version of Mk 4
- Airlanding - modified axle to fit in Horsa glider.
- Molins gun - 6 pounder gun minus carriage fitted with automatic loader built by the Molins company, a manufacturer of cigarette vending machines, and fitted to RAF De Havilland Mosquito planes for anti-ship warfare.
- 57mm Gun M1 - US built version; although based on Mk II, it had the "original" L/50 barrel and lacked muzzle brake. Was produced with the below carriage types:
- M1
- M1A1 - US wheels and tyres
- M1A2 - improved traverse mechanism
- M1A3 - modified towing hook; the first version to be adopted by the US Army
- M2 - modified trails
- M2A1 - improved elevation mechanism, didn't enter service
[edit] Ammunition
| Available ammunition | |||||
| Type | Model | Weight, kg | Filler | Muzzle velocity, m/s (L/43 guns) | Muzzle velocity, m/s (L/50 guns) |
| AP | Shot, AP, Mks 1 to 7 | 2.86 | - | 853 | 892 |
| APC (from September 1942) | Shot, APC, Mk 8T | 2.86 | - | 846 | 884 |
| APCBC (from January 1943) | Shot, APCBC, Mk 9T | 3.23 | - | 792 | 831 |
| APCR (from October 1943) | Shot, APCR, Mk 1T | 1.90 | - | 1,082 | |
| APDS (from March 1944) | Shot, APDS, Mk 1T | 1.42 | - | 1,219 | |
| HE | Shell, HE, Mk 10T | approx. 3 | 820 | ||
| AP | AP Shot M70 | 2.85 | - | 853 | |
| APCBC/HE | APC Shot M86 | 3.30 | Dunnite, 34 g | 823 | |
| HE (authorized in March 1944) | HE Shell T18 / M303 | ||||
| Canister (in production from Jan. 1945) | Canister Shot T17 / M305 | ||||
[edit] Modern Day Use
The U.S. 57mm M1 gun is popular with modern-day cannoneers, as there is a relatively good supply of shell casings and projectiles.
The gun is also reportedly still in active military use with some South American countries.
[edit] See also
- 6 pounder 6 cwt AA gun
- 6 pounder 10 cwt Naval gun
[edit] References
- Zaloga, Steven J., Brian Delf - US Anti-tank Artillery 1941-45, Osprey Publishing 2005 (New Vanguard 107), ISBN 1-84176-690-9.
[edit] External links
- QF 6 pounder at LemaireSoft
- The 6 pdr 7cwt and the Molins gun
- US M-1 57 mm Anti-tank gun at Militaria: Weapons
- Armour penetration table
| British and Commonwealth artillery of World War II | ||
|---|---|---|
Tank & anti-tank guns
Field, Medium and Heavy guns
Mountain guns
Anti-aircraft guns
| ||
| Weapons of the British Empire 1722-1965 | ||
|---|---|---|
Anti-Tank Weapons
Field guns & Misc. weapons
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