68-pounder Lancaster guns were a British rifled muzzle-loading cannon of the 1850s that fired a 68-pound shell.
[2] The cannon was designed with an oval bore and had a range of about 6,500 yd (5.9 km).
[3] The gun had a tendency to burst and jam.
[4][2] They were fitted in pairs to the Arrow-class gunvessel and were used during the Crimean War.
[1][2] The muzzle of a Lancaster gun survives in the collection of the Royal Armouries at Fort Nelson.