BL 12-inch howitzer

The Ordnance BL 12-inch howitzer was a scaled-up version of the successful BL 9.2-inch siege howitzer.

BL 12-inch howitzer
12-inch howitzer Mk IV manned by Newfoundland troops training in the UK, 1942
Type	Heavy siege howitzer
Place of origin	United Kingdom
Service history
In service	1916–1945
Used by	UK and Commonwealth
Wars	World War I, World War II
Production history
Designer	Vickers
Manufacturer	Vickers
No. built	14 (Mk II); 43 (Mk IV)
Variants	Mk II, Mk IV[note 1]
Specifications
Barrel length	160 in (4.1 m) (Mk II) 207.6 in (5.27 m) (Mk IV)[1]
Shell	HE 750 lb (340 kg)
Calibre	12 inches (304.8 mm)
Recoil	Variable hydropneumatic
Carriage	siege carriage
Maximum firing range	11,340 yd (10.37 km) (Mk II) 14,350 yd (13.12 km) (Mk IV)[1]

History

Following the success of their BL 9.2-inch howitzer, Vickers designed an almost identical version scaled up to a calibre of 12 inches, the Mk II entering service on the Western Front in August 1916.^[2] Eight complete equipments are reported as arriving in August 1916 and being in action in France shortly afterwards.

It was similar but unrelated to the BL 12-inch railway howitzers Mk I, III and V produced by the Elswick Ordnance Company at the same time.

The Mk IV was a more powerful version with longer barrel produced from 1917.

Later models were used for British home defence in World War II.

Service use

Shell marked "For Fritz" is readied for loading, bombardment of Thiepval September 1916

As with other large-calibre weapons, it was operated by the Royal Garrison Artillery in World War I.

The 12-inch was dismantled and transported in six loads mounted on traction engine wheels. It was then reassembled on its static siege mounting on top of a steel holdfast, with 22 tons of earth in a box sitting on the front of the holdfast in front of the gun, to counteract the kick of firing.

Ammunition

• 
  Mk V HE shell, World War I
• 
  12-inch shell being loaded

See also

• List of siege artillery

Weapons of comparable role, performance and era

• 305 mm howitzer M1915 Russian equivalent
• Skoda 305 mm Model 1911 Austro-Hungarian equivalent

Notes

1. Mk II = Mark 2, Mk IV = Mark 4. Britain used Roman numerals to denote Marks (i.e. models) of ordnance until after World War II. Hence this article describes the second and fourth models of British BL 12-inch howizers. Marks I, III and V were the models of the unrelated BL 12-inch railway howitzer.

References

1. Hogg & Thurston 1972, page 181, 184
2. Hogg & Thurston 1972, Page 180.

Bibliography

• Dale Clarke, British Artillery 1914-1919. Heavy Artillery. Osprey Publishing, Oxford UK, 2005 ISBN 978-1-84176-788-8
• I.V. Hogg & L.F. Thurston, British Artillery Weapons & Ammunition 1914-1918. London: Ian Allan, 1972. ISBN 978-0-7110-0381-1

External links

• Newsreel showing 12" siege howitzers and other heavy weapons in action