RML 64 pounder 58 cwt
|Ordnance RML 64 pounder 58 cwt gun (converted)|
64 Pounder (58 cwt) RML gun on iron depression carriage, c1872. One of several preserved in Gibraltar
|Type||Coast defence gun|
|Place of origin||United Kingdom|
|In service||1870 - 1902|
|Designer||Lt Col William Dundas|
|Manufacturer||Royal Gun Factory|
|Variants||One mark only|
|Weight||6,496 pounds (2,947 kg)|
|Barrel length||103.27 inches (2.623 m) (bore)|
|Shell||64 pounds (29.03 kg)|
|Calibre||6.3-inch (160.0 mm)|
|Muzzle velocity||1,230 feet per second (370 m/s)|
When Britain adopted rifled ordnance in the 1860s it still had large stocks of serviceable but now obsolete smoothbore guns. Gun barrels were expensive to manufacture, so the best and most recent models were selected for conversion to rifled guns, for use as second-line ordnance, using a technique designed by William Palliser. The Palliser conversion was based on what was accepted as a sound principle that the strongest material in the barrel construction should be innermost, and hence a new tube of stronger wrought iron was inserted in the old cast iron barrel, rather than attempting to reinforce the old barrel from the outside.
This gun was based on the cast-iron barrel of the 32-pounder 58 cwt gun, which previously fired a 32 pound solid shot. The gun was bored out to 10.5 inches and a new built-up wrought iron inner tube with inner diameter of 6.29 inches was inserted and fastened in place. The gun was then rifled with 3 grooves, with a uniform twist of 1 turn in 40 calibres (i.e. 1 turn in 252 inches), and proof fired. The proof firing also served to expand the new tube slightly and ensure a tight fit in the old iron tube.
The gun mountings for coast defence in both British and colonial locations varied enormously. Carriages in both wood and iron varied in complexity – from a simple wooden garrison carriage, traversing carriages, right through to some guns mounted on Moncrieff Disappearing gun carriages.
They became obsolete for coast artillery use in 1902, whereupon most of them were scrapped and disposed of.
- RML 64 pounder 64 cwt gun the equivalent new design frontline 64-pounder gun
- Two examples in Royal Armouries, Fort Nelson, Hampshire, UK
- Guns on wooden traversing carriages, Royal Citadel, Plymouth, Devon, UK
- Gun number 237 dated 1874, one of a pair located in Digby, Nova Scotia, Canada
- Gun number 615, dated 1877 at Fort Cumberland, New Brunswick, Canada
- Gun number 327 dated 1874 - one of a number of examples on iron depression carriages, Gibraltar - from Flickr
- Gun number 774, dated 1877 preserved at Scaur Hill Fort, Bermuda
- Gun number 798, dated 1877 at King's Square, St George Bermuda
- Treatise on Construction and Manufacture of Service Ordnance, 1879, pages 233-238, 292
- 1,230 feet/second firing 64-pound projectile with charge of 8 pounds gunpowder. Treatise on Construction of Service Ordnance 1879, page 94
- Treatise on Construction and Manufacture of Service Ordnance (3rd ed), HMSO, 1886, page 219
- Treatise on the Construction and Manufacture of Ordnance in the British Service. War Office, UK, 1879
|Wikimedia Commons has media related to RML 64 pounder 58 cwt Gun.|
- Handbook for the 64 - pr. R. M. L. converted guns of 58 and 71 cwt. L. S., 1887, 1892, 1898, 1902 at State Library of Victoria