RML 64 pounder 71 cwt gun

Design

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 8 inch 65 cwt gun, which previously fired a shell weighing 50 pounds. The 8-inch 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.

Deployment

This nature of gun was initially issued for Sea Service (SS), but by 1886 were obsolete in that role and were being returned to store for re-issue for Land Service (LS). In Naval service they were deployed on many smaller British cruising warships around the world.

In Land service many were mounted for coast defence in both British and colonial locations. They were mounted on a wide variety of iron and wooden carriages. They became obsolete for coast artillery use in 1902, whereupon most of them were scrapped and disposed of.

Surviving examples