RML 64-pounder 64 cwt gun

The RML 64-pounder 64 cwt gun is a Rifled, Muzzle Loading (RML) naval, field or fortification artillery gun manufactured in England in the 19th century,^[2] which fired a projectile weighing approximately 64 pounds (29 kg). "64 cwt" refers to the gun's weight rounded up to differentiate it from other "64-pounder" guns.

RML 64-pounder 64 cwt gun
Fortification mounted MK III gun firing at Fort Glanville Conservation Park, South Australia
Type	Naval gun Fortification gun
Place of origin	United Kingdom
Service history
In service	1865–190?
Used by	British Empire
Production history
Designer	Woolwich Arsenal
Designed	1864
Manufacturer	Woolwich Arsenal Elswick Ordnance Company
Variants	Mk I, II, III
Specifications
Mass	64-long-hundredweight (3,300 kg)
Length	9.83 in (25.0 cm)[1]
Barrel length	97.5 in (248 cm) bore
Shell	64 pounds (29 kg)[2]
Calibre	6.3 inches (160 mm)
Action	RML
Breech	Muzzle-loading
Muzzle velocity	Wrought-iron tube : 1,252 feet per second (382 m/s) Mk III steel tube : 1,390 feet per second (420 m/s)[3]
Effective firing range	5,000 yards (4,600 m)[2]

Description

The calibre of 6.3 in (16 cm) was chosen to enable it to fire remaining stocks of spherical shells originally made for the obsolete 32 pounder guns if necessary.

Mark I (adopted in 1864) and Mark II (adopted 1866) guns, and Mark III guns made from 1867 – April 1871 had wrought-iron inner "A" tubes surrounded by wrought-iron coils.

Mark III guns made after April 1871 were built with toughened mild steel "A" tubes, and earlier Mark III guns were re-tubed with steel and were classified as a siege gun in land service. Remaining guns with iron tubes were used for sea service.^[4]

Rifling of all guns consisted of 3 grooves, with a uniform twist of 1 turn in 40 calibres (i.e. 1 turn in 252 in (640 cm)).^[4]

Ammunition

The gun's standard shell was "common shell", for firing on troops in cover, ships and buildings, weighed 57.4 pounds (26.0 kg) when empty with a bursting charge of 7.1 pounds (3.2 kg). Shrapnel shells could also be fired; a 66.6 pounds (30.2 kg) shell with a 9-ounce (260 g) bursting charge propelling 234 metal balls.^[5]

Surviving Examples of Guns

The sole surviving Mk I gun, at Fort George, Scotland.

• Mark I, Mark II number 164 and Mark III guns at Fort George, near Inverness, Scotland, UK
• Mark III gun number 17, on board HMS Gannet, Chatham Dockyard, UK
• Mark III gun number 294, dated 1867, Nothe Fort, Weymouth, UK
• Mark III gun at Fort Brockhurst, Gosport, UK
• Two Mark III guns, including no. 318 dated 1867 at Pendennis Castle, Cornwall, UK
• Mark III guns number 462 and 463 at Fort Glanville, Adelaide, South Australia
• Mark III gun number 739, dated 1878, Townsville, Queensland, Australia
• Mark III gun number 742 dated 1878 - ex HMQS Otter (Queensland colonial navy) example displayed in Queens Park Toowoomba, Queensland, Australia
• Two Mark III guns, including No 729 dated 1878, at Fort Lytton Historic Military Precinct, Brisbane, Australia^[6]
• Lei Yue Mun Fort's Central Battery, Hong Kong
• 6 guns at Fort Siloso, Singapore including Mark III gun Number 767, dated 1874
• RML 64-pr 64 cwt Mk 3 at Albert Park, Auckland, Auckland, New Zealand

Children posing with the Armstrong gun in the Toowoomba Botanic Gardens, 1912.

Surviving Examples of Ammunition

• RML 64pdr shell that has been fired, and RML 64 fuse at Fort Lytton Historic Military Precinct, Brisbane, Australia
• RML 64pdr Mark I shell (no fuse) is held in the collection of the Australian War Memorial, Canberra

See also

• RML 64-pounder 71 cwt gun : conversion of SBML 8-inch 65 cwt gun