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.
The calibre of 6.3 in (16 cm) was chosen to enable it to fire remaining stocks of spherical shells originally made for the obsolete 32 pounder guns if necessary.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]
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]
^ abcA Guide to Fort Glanville, South Australia. Semaphore Park, South Australia: The Fort Glanville historical association. 2000.
^1,252 feet/second firing a 64-pound projectile with 8 lb (3.6 kg) R.L.G. gunpowder is quoted for wrought-iron tubed guns in "Treatise on Construction and Manufacture of Service Ordnance, 1879", page 363. 1,390 ft/s (420 m/s) firing a 65-pound projectile using 10 lb (4.5 kg) R.L.G.4 gunpowder is quoted for Mk III steel tube gun in Table XII in "Text Book of Gunnery 1902".
^ abTreatise on Construction and Manufacture of Service Ordnance, 1879, pages 292, 261-265
A live round was found in the garden of a couple living in Pembrokeshire, UK and detonated by the local Bomb Squad. Here is a link to the news report: Milford Haven: Garden ornament turns out to be live bomb https://www.bbc.com/news/uk-wales-67602627