The 10-inch BL gun came in four Marks (I to IV) and was introduced in 1885. The Mark I was an Elwick Ordnance design while the other three marks were manufactured at Woolwich Arsenal. The guns were usually mounted in a barbette with a central pivot, similar to the early 9.2-inch guns. There was also a disappearing (HP) carriage designed for the gun. The 10-inch BL gun had an effective range of 10,000 yards. Originally intended for use by the Royal Navy, the 10-inch gun was used by the British in coastal defence batteries around the World.