BL 6 inch gun Mk V

The BL 6 inch gun Mk V was an early Elswick Ordnance Company breech-loading naval gun originally designed to use the old gunpowder propellants. They were used for coast defence around the British Empire.

BL 6 inch gun Mk V
Class Vehicle
Type Other
Manufacturer Armstrong Whitworth
Origin United Kingdom - UK (Great Britain)
Country Name Origin Year
United Kingdom - UK (Great Britain) 1884
Country Name Operational Year Retirement Year
Australia View
Germany 1884 1945 View
Thailand (Siam) View
New Zealand View
ManufacturerName Production From Production To Quantity
Armstrong Whitworth View

This was an Elswick Ordnance export design, completely different from and longer (30-calibres, 183.5 inch bore) than the contemporary 26-calibres British naval service 6-inch Mk III, IV and VI guns designed by the Royal Gun Factory, although it fired the same 100-pound projectiles. The gun was of a complex all-steel built-up construction, of a steel A-tube surrounded by multiple steel hoops, breech-piece and jacket.

Several were acquired by the British government for coast defence in the UK and were given the designation 6-inch gun Mark V. The breech fittings and firing mechanism were modified in British service to standardize them with the British service guns, Mark IV and VI. The breech-screw was locked by turning to the left, unlike standard service guns made by the Royal Gun Factory, which all locked to the right. Rifling consisted of 28 grooves of the polygroove "Elswick section" type, increasing from 0 to 1 turn in 30 calibres (i.e. 1 turn in 180 inches) at the muzzle.

They were also exported for use as coast-defence guns in Hong Kong, New Zealand, Australian colonies and Siam (Thailand), typically as disappearing guns.

Type Coast defence gun
Place of origin United Kingdom
Service history
In service 1884 - 1945
Used by United Kingdom
Australian Colonies
New Zealand
Production history
Designer Elswick Ordnance Company(EOC)
Manufacturer EOC
Unit cost £3,400
Weight 5 tons barrel & breech
Barrel length 183.5 inches (4,661 mm) bore (30.58 calibres);
192 inches (4,877 mm) bore and chamber (32 calibres)
Shell 100 pounds (45.36 kg)
Calibre 6-inch (152.4 mm)
Breech 3 motion interrupted screw. Elswick cup obturation
Muzzle velocity 1,890 feet per second (576 m/s)
Maximum firing range 8,000 yards (7,300 m)

End notes