Ordnance BL 15 pounder

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Ordnance BL 15 pounder
British artillery safrica c1900.jpg
15 pounder in South Africa during the Second Boer War
Type Field gun
Place of origin United Kingdom United Kingdom
Service history
In service 1892–1918
Used by British Empire
Wars Second Boer War
World War I
Specifications
Barrel length 84 inch[1]

Shell Separate loading BL, 14 lb (6.4 kg) shrapnel
Calibre 3 inch (76.2 mm)
Elevation -5° - 16°[1]
Rate of fire 7-8 rds/min[2]
Muzzle velocity 1590 ft/s[3]
Maximum firing range 6000 yds[4]

The Ordnance BL 15 pounder, otherwise known as the 15 pounder 7 cwt, was the British Army's field gun in the Second Boer War and some remained in limited use in minor theatres of World War I. It could fire a shell of 3-inch diameter with a maximum weight of 15 pounds (6.8 kg), hence its name which differentiated it from its predecessor "12 pounder" 3-inch gun which fired shells weighing only 12.5 pounds (5.7 kg).[5]

History[edit]

The gun was a modified version of the previous BL 12 pounder 7 cwt gun of 1883. When the modern smokeless propellant cordite replaced gunpowder in 1892 it was decided that the 12 pounder was capable of firing a heavier shell up to 15 lb (6.8 kg). A 14 pound shell was adopted and the gun was renamed a 15 pounder.[6]

Mk I carriage : recoil was controlled by drag-shoes. These were placed under the wheels, and were connected by chains and cables to the wheel hubs and the trail.[7]

Mk II carriage : this had the same drag-shoe system and also a hydraulic buffer. This only allowed a short recoil, and was not successful.[7]

Mk III carriage : In 1899 a rudimentary recoil system was added, consisting of a "spade" beneath the axle which dug in when the gun recoiled, connected by a steel wire to a spring in a cylinder on the trail. Mk I and II carriages fitted with these were known as Mk 1* and Mk II*. The latter retained the hydraulic buffer.[7]

Although the whole gun jumped and moved backwards on firing, the spring returned it to firing position and hence still increased the rate of fire compared to the old model without any recoil mechanism.[8] Hogg and Thurston comment ironically : "It is said that it checked it [recoil] so well that the gun usually recoiled 1 foot and jumped forward 2 feet".[9]

Other Mks of carriage followed, all with axle-spades, but without buffers.

From 1904 the BL 15 pounder was superseded by the modern QF 18 pounder. Remaining BL 15 pounders were upgraded as the BLC 15 pounder to equip the Territorial Force with an "ersatz QF gun".[8]

Combat use[edit]

The gun was normally towed by 6 horses, in 3 pairs.

Second Boer War[edit]

Australians with gun, Second Boer War, 1901

349 guns were in service in the Second Boer War 1899–1902 and fired 166,548 shells out of the British total of 233,714.[10]

While the gun could fire a shell up to approximately 5800-5900 yards, the No. 56 time and percussion fuze in use in 1899 could only be set for a maximum timed range of 4100 yards because it only burned for 13 seconds. The shrapnel shells in use were usually time-set to burst in the air above and in front of the enemy. Hence the gunners had to get within approximately 4200 yards of the enemy to fire on them. The fuze could be set to explode on contact (percussion) up to the maximum range, but shrapnel exploding on contact was of little use. This was rectified later in the war by the No. 57 "blue fuze" which could be time set up to 5800-5900 yards.[11][12]

World War I[edit]

Gun of 7th Field Battery towed by oxen, German East Africa, World War I

7th Field Battery (4 guns, originally No. 2 and No. 6 Light Batteries) towed by oxen and known as the Oxo Battery and manned by Mauritian and South African gunners fought in the German East Africa campaign in World War I.[13]

Ammunition[edit]

BL15pdrCorditeCartridgeBoerWar.jpg
No56FuzeMkIVC.jpg
15pdrShrapnelShellMkVIDiagram.jpg
3inchCaseShotMkVDiagram.jpg
TFrictionTubeMkIV.jpg
1534 oz Cordite cartridge, early 1900s
No. 56 Fuze
as used in Second Boer War
Mk VI Shrapnel shell
Mk V Case shot
Mk IV T friction tube

See also[edit]

Weapons of comparable role, performance and era[edit]

Surviving examples[edit]

Notes and references[edit]

  1. ^ a b Hogg & Thurston 1973, page 71
  2. ^ Hall June 1971
  3. ^ Hogg & Thurston 1974 quote 1,590 ft/s (480 m/s) in WWI. Hall December 1972 quotes 1,574 ft/s (480 m/s) in the Second Boer War. The difference may be the propellant.
  4. ^ Hogg & Thurston 1972 quote 6000 yards in WWI. Hall June 1971 quotes 5600 yds in the Second Boer War.
  5. ^ The British at that time traditionally identified smaller guns by the maximum weight of shell they could fire, arbitrarily rounded up or down.
  6. ^ Clarke 2004, page 17-18
  7. ^ a b c Hall, June 1973
  8. ^ a b Clarke 2004, page 18
  9. ^ Hogg & Thurston 1972, page 70
  10. ^ Appendices 28 and 29 of the Royal Commission on the War in South Africa
  11. ^ Hall, December 1975
  12. ^ Hall, December 1972
  13. ^ Farndale 1988, page 316

Bibliography[edit]

External links[edit]