RML 16-inch 80-ton gun
Introduction '''RML 16-inch 80-ton guns''' were large rifled muzzle-loading guns intended to give the largest British battleships parity with the large guns being mounted by Italian and French ships in the Mediterranean Sea in the 1870s.
Design and history Gun barrel constructionThe gun was constructed of a toughened mild steel inner "A" tube surrounded by multiple wrought-iron coils, breech-piece and a jacket. Rifling was of the "polygroove plain section" type, with 33 grooves increasing from 0 to 1 turn in 50 calibres (i.e. 1 turn in ) at the muzzle.After a long design and experimentation period beginning in 1873,  with its four guns, became the only ship to mount them, in 1880.By that time such muzzle-loading guns were already obsolescent and were being superseded by a new generation of rifled breechloading guns.Two more guns were mounted for coastal defence in the Admiralty Pier Turret at Dover.
Ammunition This was a second-generation RML gun, equipped with polygroove rifling and firing only studless ammunition and using automatic gas-checks for rotation.File:RML 16 inch 112.5 lb quarter charge prism brown cartridge diagram.jpg|112½-pound ¼ charge brown prism powder cartridge
Surviving examples The two guns in the Admiralty Pier Turret as they are todayThe only two remaining example are in the ruins of the Admiralty Pier Turret, Dover, Kent, UK.
See also *List of naval guns
Notes and references
Bibliography *  Text Book of Gunnery, 1887 . London: Printed for His Majesty's Stationery Office, by Harrison and Sons, St. Martin's Lane*  Text Book of Gunnery, 1902 . London: Printed for His Majesty's Stationery Office, by Harrison and Sons, St. Martin's Lane* Sir Thomas Brassey,  The British Navy, Volume II. London: Longmans, Green and Co. 1882*N.J.M. Campbell,  British Super-Heavy Guns
External links * Flickr photos of the guns in the Dover turret :    * Photograph of Palliser projectile at Royal Marines Museum, Portsmouth, from Flickr