The BL 15-inch Mark I succeeded the BL 13.5-inch Mk V naval gun. It was the first British 15-inch (381 mm) gun design and the most widely used and longest lasting of any British designs, and arguably the most successful heavy gun ever developed by the Royal Navy.[3] It was deployed on capital ships from 1915 until 1959 and was a key Royal Navy gun in both World Wars.
This gun was an enlarged version of the successful BL 13.5-inch Mk V naval gun. It was specifically intended to arm the new Queen Elizabeth-class battleships as part of the British response to the new generation of Dreadnought battleships Germany was building, during the naval arms race leading up to World War I. Due to the urgency of the times, the normally slow and cautious prototype and testing stages of a new gun's development were bypassed, and it was ordered straight from the drawing board. Despite its hurried development process, the gun met all expectations and was a competitive battleship main armament throughout both World Wars. According to an American report produced after World War II, the British 15 inch Mk I was the most reliable and accurate battleship main armament of the war, though other guns and mountings had superior individual features.[4]
Animation representing the loading cycle of the Mark I turret for the BL 15 inch Mark I.
The barrel was 42 calibres long (i.e., length of bore was 15 in x 42 = 630 in) and was referred to as "15 inch/42". Overall length of gun: 650.4 inches, Weight of gun, excluding breech mechanism: 97 tons 3cwt. Weight of breech mechanism: 2 tons 17cwt. Rifling: polygroove, 76 grooves, uniform right-hand twist of one turn in 30 calibres. This wire-wound gun fired at a muzzle velocity of 2,450 ft/s (749 m/s) (4 crh shell), 2,640 ft/s (6 crh shell) with supercharge. Weight of shell: 1,920 lbs (4 AP crh shell), 1,938 lbs (6 crh AP shell – 1937). Weight of charge: 428 lbs cordite, 490 lbs cordite for supercharge.[2][5] The firing life of a 15-inch gun was approximately 335 full charge firings using standard charges, after which it had to be re-lined.[6]
Mounting
All shipboard mounts of the gun were in twin turrets. Excepting on the battlecruiser HMS Hood, all mountings were designated Mk I, with an as-built maximum elevation of 20°, though some were subject to later modifications. HMS Hood had its guns in a unique mounting, designated Mk II. Incorporating experience from the Battle of Jutland, the Mk II mounting had a maximum elevation of 30°, thus increasing the maximum range.[7] In the 1930s a modification of the Mk I mounting, designated the Mk I (N), was introduced for use in those capital ships that were completely reconstructed. The Mk I (N) mounting also increased the maximum elevation from 20° to 30°.[8] Maximum range in shipboard mountings was 33,550 yards (30,680 m) (30° elevation).[2] During World War II unreconstructed older battleships, with gun elevation limited to 20°, were supplied with supercharges to increase their maximum range to 29,930 yards (27,370 m) at 2638 ft/s (804 m/s) using the Mk XVIIB or Mk XXII projectile, while HMS Vanguard could theoretically range to 37,870 yards (34,630 m) while using supercharges at a gun elevation of 30°.[2] Coastal artillery mountings with higher elevations could reach 44,150 yards (40,370 m). The Mk I mounting had a revolving weight of 750 tons (1915) and 785 tons (1935). The Mk I (N) had a revolving weight of 815 tons; the Mk I (N) RP12 mounts of HMS Vanguard had a revolving weight of 855 tons. The Mk II mounts of HMS Hood had a revolving weight of 860 tons.[9]
In service employment
In battle
BL 15-inch Mk I naval guns firing, interwar view of a Queen Elizabeth-class battleship - the right-hand gun in each turret has just fired and the degree of recoil is evident
The BL 15-inch Mark I gun proved its effectiveness at the Battle of Jutland in 1916, scoring hits out to 19,500 yards (17,800 m), a record for naval gunnery at that time.[10]
In World War II the gun was responsible for the longest range shell-hit ever scored by one battleship on another in combat. At the Battle of Calabria on 9 July 1940, HMS Warspite gained a hit on the Italian battleship Giulio Cesare with her first salvo at 26,400 yards (24,100 m).[11] In the Attack on Mers-el-Kébir, when the French fleet was largely neutralised following the fall of France to the Germans, the BL 15-inch Mark I gun (arming HMS Hood, HMS Valiant and HMS Resolution) was responsible for the destruction by a magazine explosion of the old battleship Bretagne, and the disabling and beaching (deliberate running aground in shallow water) of the old battleship Provence and the new battleship Dunkerque. Dunkerque's main 225mm armour belt was twice penetrated by 15-inch shells, which destroyed its fighting and steaming abilities.[12]
Warships
Forward BL 15-inch Mark I (N) mounts of the battlecruiser HMS Renown c. 1945
These guns were used on several classes of battleships from 1914 until HMS Vanguard, the last battleship to be built for the Royal Navy, completed in 1946.
Warships armed with the BL 15-inch Mark I gun:
Queen Elizabeth-class battleships (Five ships with eight guns each – 3 ships converted to Mk I (N))
Revenge-class battleships (Five ships with eight guns each)
Renown-class battlecruisers (Two ships with six guns each – 1 ship converted to Mk I (N))
HMS Hood – battlecruiser (Eight guns, Mk II mounting)
HMS Vanguard – battleship (Eight guns in mountings taken from Courageous and Glorious converted to Mk I (N), with additional armour, designated: Mk I (N) (RP12). The turret supports were designed to withstand supercharge firings.Vanguard was unique among British battleships in having remote power control (RPC) for her main battery turrets.[13]
Coastal batteries
Two coastal guns ("Clem" and "Jane") were mounted near Wanstone Farm in Kent in the 1940s, and were used extensively for cross-Channel fire throughout the war.
186 guns were manufactured between 1912 and 1918.[14] They were removed from ships, refurbished, and rotated back into other ships over their lifetime.
Burt, R. A. (2012). British Battleships, 1919–1939 (2nd ed.). Annapolis, Maryland: Naval Institute Press. ISBN978-1-59114-052-8.
Buxton, Ian Lyon (1978). Big Gun Monitors. Tynemouth: World Ship Society. ISBN0-905617-06-1.
Campbell, John (1985). Naval Weapons of World War II. Annapolis, Maryland: Naval Institute Press. ISBN0-87021-459-4.
Jordan, John and Dumas, Robert (2009) French Battleships 1922–1956, Seaforth Publishing, Barnsley. ISBN978 1 59114 416 8
Raven, Alan; Roberts, John (1976). British Battleships of World War Two: The Development and Technical History of the Royal Navy's Battleship and Battlecruisers from 1911 to 1946. Annapolis, Maryland: Naval Institute Press. ISBN0-87021-817-4.
Roskill, Captain Stephen Wentworth (1974). H.M.S. Warspite: The Story of a Famous Battleship. London: Futura Publications. ISBN0-86007-172-3.
External links
Wikimedia Commons has media related to BL 15 inch Mk I naval gun.
Information at Naval Weapons website
The IWM guns
"Closing the breech of a 15 inch gun at Explosion!" The Museum of Naval Firepower, Gosport, UK on YouTube
Terry Gander,
January 06, 2023
inch, naval, inch, mark, succeeded, inch, naval, first, british, inch, design, most, widely, used, longest, lasting, british, designs, arguably, most, successful, heavy, ever, developed, royal, navy, deployed, capital, ships, from, 1915, until, 1959, royal, na. The BL 15 inch Mark I succeeded the BL 13 5 inch Mk V naval gun It was the first British 15 inch 381 mm gun design and the most widely used and longest lasting of any British designs and arguably the most successful heavy gun ever developed by the Royal Navy 3 It was deployed on capital ships from 1915 until 1959 and was a key Royal Navy gun in both World Wars BL 15 inch Mark I naval gunAs mounted on monitor HMS Terror 1915TypeNaval gunPlace of originUnited KingdomService historyIn service1915 1959Used byUnited KingdomWarsWorld War I World War II Cold WarProduction historyDesigned1912Produced1912 1918No built186SpecificationsMass100 long tons 100 t 1 Length650 4 inches 16 52 m 1 Barrel length630 inches 16 m L42Shellseparate charges and shellShell weight1 938 pounds 879 kg Calibre15 inch 381 0 mm Recoil46 inches 1 2 m 1 Rate of fire2 rounds per minuteMuzzle velocity2 450 feet per second 750 m s 2 640 feet per second 800 m s with superchargeMaximum firing range33 550 yards 30 680 m Mk XVIIB or Mk XXII streamlined shell 30 2 HMS Vanguard 37 870 yards 34 630 m 30 with supercharges Contents 1 Design 1 1 Gun 1 2 Mounting 2 In service employment 2 1 In battle 2 2 Warships 2 3 Coastal batteries 3 Production 4 World War II ammunition 5 See also 5 1 Weapons of comparable role performance and era 6 References 6 1 Bibliography 7 External linksDesign Edit Diagram showing gun barrel construction Gun Edit This gun was an enlarged version of the successful BL 13 5 inch Mk V naval gun It was specifically intended to arm the new Queen Elizabeth class battleships as part of the British response to the new generation of Dreadnought battleships Germany was building during the naval arms race leading up to World War I Due to the urgency of the times the normally slow and cautious prototype and testing stages of a new gun s development were bypassed and it was ordered straight from the drawing board Despite its hurried development process the gun met all expectations and was a competitive battleship main armament throughout both World Wars According to an American report produced after World War II the British 15 inch Mk I was the most reliable and accurate battleship main armament of the war though other guns and mountings had superior individual features 4 Animation representing the loading cycle of the Mark I turret for the BL 15 inch Mark I The barrel was 42 calibres long i e length of bore was 15 in x 42 630 in and was referred to as 15 inch 42 Overall length of gun 650 4 inches Weight of gun excluding breech mechanism 97 tons 3cwt Weight of breech mechanism 2 tons 17cwt Rifling polygroove 76 grooves uniform right hand twist of one turn in 30 calibres This wire wound gun fired at a muzzle velocity of 2 450 ft s 749 m s 4 crh shell 2 640 ft s 6 crh shell with supercharge Weight of shell 1 920 lbs 4 AP crh shell 1 938 lbs 6 crh AP shell 1937 Weight of charge 428 lbs cordite 490 lbs cordite for supercharge 2 5 The firing life of a 15 inch gun was approximately 335 full charge firings using standard charges after which it had to be re lined 6 Mounting Edit All shipboard mounts of the gun were in twin turrets Excepting on the battlecruiser HMS Hood all mountings were designated Mk I with an as built maximum elevation of 20 though some were subject to later modifications HMS Hood had its guns in a unique mounting designated Mk II Incorporating experience from the Battle of Jutland the Mk II mounting had a maximum elevation of 30 thus increasing the maximum range 7 In the 1930s a modification of the Mk I mounting designated the Mk I N was introduced for use in those capital ships that were completely reconstructed The Mk I N mounting also increased the maximum elevation from 20 to 30 8 Maximum range in shipboard mountings was 33 550 yards 30 680 m 30 elevation 2 During World War II unreconstructed older battleships with gun elevation limited to 20 were supplied with supercharges to increase their maximum range to 29 930 yards 27 370 m at 2638 ft s 804 m s using the Mk XVIIB or Mk XXII projectile while HMS Vanguard could theoretically range to 37 870 yards 34 630 m while using supercharges at a gun elevation of 30 2 Coastal artillery mountings with higher elevations could reach 44 150 yards 40 370 m The Mk I mounting had a revolving weight of 750 tons 1915 and 785 tons 1935 The Mk I N had a revolving weight of 815 tons the Mk I N RP12 mounts of HMS Vanguard had a revolving weight of 855 tons The Mk II mounts of HMS Hood had a revolving weight of 860 tons 9 In service employment EditIn battle Edit BL 15 inch Mk I naval guns firing interwar view of a Queen Elizabeth class battleship the right hand gun in each turret has just fired and the degree of recoil is evident The BL 15 inch Mark I gun proved its effectiveness at the Battle of Jutland in 1916 scoring hits out to 19 500 yards 17 800 m a record for naval gunnery at that time 10 In World War II the gun was responsible for the longest range shell hit ever scored by one battleship on another in combat At the Battle of Calabria on 9 July 1940 HMS Warspite gained a hit on the Italian battleship Giulio Cesare with her first salvo at 26 400 yards 24 100 m 11 In the Attack on Mers el Kebir when the French fleet was largely neutralised following the fall of France to the Germans the BL 15 inch Mark I gun arming HMS Hood HMS Valiant and HMS Resolution was responsible for the destruction by a magazine explosion of the old battleship Bretagne and the disabling and beaching deliberate running aground in shallow water of the old battleship Provence and the new battleship Dunkerque Dunkerque s main 225mm armour belt was twice penetrated by 15 inch shells which destroyed its fighting and steaming abilities 12 Warships Edit Forward BL 15 inch Mark I N mounts of the battlecruiser HMS Renown c 1945 These guns were used on several classes of battleships from 1914 until HMS Vanguard the last battleship to be built for the Royal Navy completed in 1946 Warships armed with the BL 15 inch Mark I gun Queen Elizabeth class battleships Five ships with eight guns each 3 ships converted to Mk I N Revenge class battleships Five ships with eight guns each Renown class battlecruisers Two ships with six guns each 1 ship converted to Mk I N HMS Hood battlecruiser Eight guns Mk II mounting Courageous class battlecruisers Two ships with four guns each Erebus class monitors Two ships with two guns each Marshal Ney class monitors Two ships with two guns each Roberts class monitors Two ships with two guns each HMS Vanguard battleship Eight guns in mountings taken from Courageous and Glorious converted to Mk I N with additional armour designated Mk I N RP12 The turret supports were designed to withstand supercharge firings Vanguard was unique among British battleships in having remote power control RPC for her main battery turrets 13 Coastal batteries Edit Two coastal guns Clem and Jane were mounted near Wanstone Farm in Kent in the 1940s and were used extensively for cross Channel fire throughout the war Five guns were mounted in Singapore at Johore battery and Buona Vista Battery in the 1930s X turret Mk II mount of HMS Hood trained forward to port 1926 One of Singapore s 15 inch coastal defence guns elevated for firingProduction Edit Two 15 inch guns outside the Imperial War Museum the nearer gun from HMS Ramillies the other from HMS Roberts 186 guns were manufactured between 1912 and 1918 14 They were removed from ships refurbished and rotated back into other ships over their lifetime Elswick Ordnance Company Elswick Newcastle 34 Armstrong Whitworth Openshaw Manchester 12 William Beardmore amp Company Parkhead Glasgow 37 Coventry Ordnance Works Coventry 19 Royal Gun Factory Woolwich 33 Vickers Son and Maxim Barrow in Furness 49Two guns one formerly from HMS Ramillies left gun and the other originally mounted in HMS Resolution but later moved to HMS Roberts right gun are mounted outside the Imperial War Museum in London World War II ammunition Edit 108 lb Cordite cartridge charge AP shell Mk XXII BNT AP shell and cap as fired by HMS Malaya into Genoa on 9 February 1941 An AP shell in the process of being hoisted to the gun breech Singapore 1940See also EditList of naval gunsWeapons of comparable role performance and era Edit 38 cm SK L 45 Max German counterpart Cannone navale da 381 40 Italian counterpartReferences Edit a b c Ian Buxton p 181 a b c d John Campbell p 25 Raven and Roberts p 17 Raven and Roberts p 411 Raven and Roberts pp 411 423 Roskill p 89 Raven and Roberts p 65 Raven and Roberts p 226 Raven and Roberts p 423 Burt p 73 Burt p 133 Jordan and Dumas pp 77 82 Raven and Roberts p 326 Ian Buxton p 179 Bibliography Edit Burt R A 2012 British Battleships 1919 1939 2nd ed Annapolis Maryland Naval Institute Press ISBN 978 1 59114 052 8 Buxton Ian Lyon 1978 Big Gun Monitors Tynemouth World Ship Society ISBN 0 905617 06 1 Campbell John 1985 Naval Weapons of World War II Annapolis Maryland Naval Institute Press ISBN 0 87021 459 4 Jordan John and Dumas Robert 2009 French Battleships 1922 1956 Seaforth Publishing Barnsley ISBN 978 1 59114 416 8 Raven Alan Roberts John 1976 British Battleships of World War Two The Development and Technical History of the Royal Navy s Battleship and Battlecruisers from 1911 to 1946 Annapolis Maryland Naval Institute Press ISBN 0 87021 817 4 Roskill Captain Stephen Wentworth 1974 H M S Warspite The Story of a Famous Battleship London Futura Publications ISBN 0 86007 172 3 External links Edit Wikimedia Commons has media related to BL 15 inch Mk I naval gun Information at Naval Weapons website The IWM guns Images from the Vickers Photographic Archives Closing the breech of a 15 inch gun at Explosion The Museum of Naval Firepower Gosport UK on YouTube Terry Gander Twentieth century British coast defence guns Retrieved from https en wikipedia org w index php title BL 15 inch Mk I naval gun amp oldid 1096275327, wikipedia, wiki, book, books, library,
