BL 18 inch railway howitzer

BL 18 inch railway howitzer
Example at Catterick, 12 December 1940
Type	Railway howitzer
Place of origin	United Kingdom
Service history
In service	1920 - 1945
Used by	United Kingdom
Wars	World War II
Production history
Manufacturer	Elswick Ordnance Company
No. built	5
Specifications
Weight	85.7 tons (barrel & breech)
Barrel length	Bore: 52 ft (16 m) (34.7 calibres)
Shell	HE; 2,500 lb (1,134 kg)
Calibre	18-inch (457.2 mm)
Elevation	0° - 40°
Traverse	2° L & R
Muzzle velocity	1,880 ft/s (570 m/s)
Effective firing range	22,300 yd (20,400 m)

The BL 18 inch railway howitzer (formally Ordnance BL 18 inch Mk I howitzer on truck, railway) was a British railway gun developed during World War I. Part of the progression of ever-larger howitzers on the Western Front, it did not enter service until 1920.

Five guns and two complete equipments on railway wagons were produced. After World War I there was no use for such large but relatively short-ranged weapons and they were placed in storage. In World War II the two wagons were used to mount 13.5 inch guns, which were capable of engaging targets on the German-occupied Channel coast of France. In late 1940 one 18-inch howitzer was mounted on the railway mounting nicknamed "Boche Buster" which had been used in World War I to carry a 14-inch gun. It was deployed at Bishopsbourne in Kent on the Elham to Canterbury Line as a coast defence gun as a precaution against possible German invasion. The gun's range was insufficient for cross-Channel firing and hence it was never fired in action.

A single gun barrel, number one, survives. Thus gun was tested at MoD Shoeburyness in 1920 before being moved away from the site for twenty years, probably to the Royal Arsenal at Woolwich. In 1940 it returned to Shoeburyness to be used in testing. Post war it continued to be used in testing until 1959. The gun's final firings were a series of test where it fired 1000 pound bombs with a much reduced charge. In 2008 the weapon was put on display at the Royal Artillery headquarters at Larkhill. In March 2013 it was loaned to the Spoorwegmuseum, the Dutch national rail museum. In September 2013 it was moved to the Royal Armouries artillery museum at Fort Nelson, Hampshire. It is mounted on a proofing carriage, a gun carriage with very limited elevation and traverse intended for test firing.