12-inch/40-caliber gun

12"/40 caliber Mark 3 and Mark 4 USS Ohio (BB-12) 12-inch 40 cal guns.jpeg 300px 12"/40 guns of the ship's forward gun turret, photographed circa 1907-1908. Note Sailors strolling on deck; bell mounted on the pilothouse face; and 3-pounder guns mounted on the superstructure. View of Ohio BB-12 2 and her forward 12"/40 caliber guns in the Mark 4 turret in 1916. United States Naval gun YES YES 1902 United States Navy World War I Bureau of Ordnance 1899 U.S. Naval Gun Factory Mark 3: 41 (Nos. 15–41, 50–56) Mark 4: 10 (Nos. 49, 58–60, 150–154, 179) Mark 3 and Mark 4 116480 lb (with breech) 114960 lb (without breech) 40 ft 0 in m 2 bore (40 calibers) 870 lb armor-piercing 12 in mm 3 0.66 rounds per minute (as commissioned) 2 rounds per minute (after 1906) 2800 ft/s (as commissioned) 2600 ft/s (first derating) 2400 ft/s (final derating) 19000 yd 0 at 15.5° elevation Mark 4: −3° to +15° Mark 5: −7° to +20° −150° to +150° The 12"/40 caliber gun (spoken as "twelve-inch-forty--caliber") were used for the primary batteries of the United States Navy's last class of monitors and the Maine battleship 0 and Virginia battleship 0 pre-dreadnought battleships.Navweaps 2016 Design The 12 in 0 on out/40 caliber gun was developed after the Spanish–American War to use the new smokeless powder that had recently been adopted by the Navy. The Mark 3, gun Nos. 15–48 and 50–56, was constructed of tube, jacket, and eight hoops. It was found that the early guns suffered from excessive bore erosion, in an attempt to fix this the Navy reduced the propellant charges to reduce the muzzle velocity, because of this the Mark 4, gun Nos. 49, 58–60, 150–154, and 179, was similar to the Mark 3 but with a smaller chamber for the reduced propellant charge.Navweaps 2016Friedman 2011 Service history The guns mounted in the Virginia-class battleships were in an unusual two-level turret with the 8 in 0 on out/45 caliber guns on top of the larger 12-inch guns. This arrangement ultimately proved unsuccessful but helped the Navy in the successful development of superfiring turrets later used in the dreadnought South Carolina BB-26 2.Navweaps 2016 Incident Gun No. 49, while testing powder at the Naval Proving Ground, had the entire muzzle and chase blow off. The board appointed to investigate came to the conclusion that the new powder, while performing properly, caused a pressure along the chase that was dangerously close to the strength curve. It was decided that when the guns were withdrawn to be relined they would add an additional hoop that extended to the muzzle would be placed on the chase.Mason 1905 14 Naval Service ShipGun InstalledGun MountArkansas BM-7Mark 3 or 4: 12"/40 caliberMark 4: 1 × twin turretsNevada BM-8Mark 3 or 4: 12"/40 caliberMark 4: 1 × twin turretsFlorida BM-9Mark 3 or 4: 12"/40 caliberMark 4: 1 × twin turretsWyoming BM-10Mark 3 or 4: 12"/40 caliberMark 4: 1 × twin turretsMaine BB-10Mark 3 or 4: 12"/40 caliberMark 4: 2 × twin turretsMissouri BB-11Mark 3 or 4: 12"/40 caliberMark 4: 2 × twin turretsOhio BB-12Mark 3 or 4: 12"/40 caliberMark 4: 2 × twin turretsVirginia BB-13Mark 3 or 4: 12"/40 caliberMark 5: 2 × dual-caliber turretsNebraska BB-14Mark 3 or 4: 12"/40 caliberMark 5: 2 × dual-caliber turretsGeorgia BB-15Mark 3 or 4: 12"/40 caliberMark 5: 2 × dual-caliber turretsNew Jersey BB-16Mark 3 or 4: 12"/40 caliberMark 5: 2 × dual-caliber turretsRhode Island BB-17Mark 3 or 4: 12"/40 caliberMark 5: 2 × dual-caliber turrets Notes 2 References Books Friedman Norman Norman Friedman https://books.google.com/books?id=yh3OAwAAQBAJ Naval Weapons of World War One Seaforth Publishing 2011 978-1-84832-100-7 Mason Newton E. Newton E. Mason Report of the Chief of the Bureau of Ordnance to the Secretary of the Navy https://books.google.com/books?id=vTksAAAAYAAJ Government Printing Office Washington, D.C. 1 October 1905 13 October 2016 Online sources http://www.navweaps.com/Weapons/WNUS_12-40_mk3.php United States of America 12"/40 (30.5 cm) Mark 3 and Mark 4 Navweaps 19 July 2016 13 October 2016 Navweaps 2016 External links Bluejackets Manual, 1917, 4th revision: US Navy 14-inch Mark 1 gun June 2017 Category:Naval guns of the United States Category:305 mm artillery