BL 12-inch railway howitzer explained

Ordnance BL 12-inch Howitzer Mk I, III, V on truck, railway
Origin:United Kingdom
Type:Railway howitzer
Is Artillery:yes
Is Ranged:yes
Is Explosive:yes
Is Uk:yes
Service:1916–1940
Used By:United Kingdom
Wars:First World War
Designer:Elswick Ordnance Company
Manufacturer:Elswick Ordnance Company
Number:81
Variants:Mk I, III, V[1]
Part Length:Mk I: 12feet
Mk III & V: 17inchesft3inchesin (ftin)[2]
Cartridge:HE
750lb
Caliber:12-inch (305 mm)
Velocity:Mk I: 1175ft/s
Mk III & V: 1468ft/s
Range:Mk I: 11132yd
Mk III: 15000yd
Mk V: 14350yd
Elevation:Mk I & III: 40° - 65°
Mk V: 20° - 65°
Traverse:Mk I & III: 20° L & R
Mk V: 120° L & R
Filling Weight:83lb 3oz (37.96 kg) Amatol

The British Ordnance BL 12 inch howitzer on truck, railway, a type of railway gun, was developed following the success of the 9.2-inch siege howitzer. It was similar but unrelated to the 12-inch siege howitzers Mk II and IV.

Design and development

Mark I

Mk I was introduced from March 1916. It is identified by its short barrel and recuperator above the barrel.

Mark III

The longer-barrelled Mk III soon followed, with a heavier breech to balance the gun. It retained the recuperator above the barrel.

Mark V

Mk V, dating from July 1917, moved the recoil buffer and recuperator into a single housing below the barrel, which was common for all new British artillery developed during World War I. It also had a lighter breech with the gun balanced by the redesigned recoil system and altered gun positioning on the cradle.[3] Mk V also relocated the loading platform from the railway wagon to the revolving gun mounting, which now allowed 120° of traverse, and by overhanging the opposite side provided crew access when the gun fired to the side (90° traverse) and also helped to balance it.[3]

Combat service

All 3 versions served on the Western Front in World War I, usually in 2-gun batteries, operated by the Royal Garrison Artillery.

Mk III and MK V were deployed for the home defence of Great Britain in World War II.

See also

Bibliography

Further reading

External links

Notes and References

  1. Mk I = Mark 1, Mk III = Mark 3, Mk V = Mark 5. Britain used Roman numerals to denote Marks (i.e. models) of ordnance until after World War II. Hence this article covers the first, third and fifth models of British 12-inch howitzers. Mks II and IV were the unrelated BL 12-inch siege howitzer.
  2. Hogg & Thurston 1972, page 179, 183, 187
  3. Hogg & Thurston 1972, page 186