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58-446: F33 may refer to : HMS Somali (F33) , a 1937 British Royal Navy Tribal-class destroyer Recurrent depressive disorder ICD-10 code Hirth F-33 , an aircraft engine F-33, Another name for the KF-21 . [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as

116-510: A 1 ⁄ 4 charge, to make up the full service charge. Howitzer cartridges, both BL and separate QF, contained a central core of cordite surrounded by several stacked ring-shaped bags of cordite. To obtain the appropriate "charge" for the required range and angle of elevation, the gunner discarded one or more rings before loading. See charge for how Ordnance QF 25-pounder charges varied in World War II. The case, usually brass, holding

174-438: A Crossley pad with an interrupted thread screw block e.g. a Welin screw . The shell was loaded via the breech, followed by the propellant charge in a cloth bag. A single-use " vent sealing tube ", a type of primer not dissimilar in appearance to a blank rifle round, was inserted into the breech for firing the gun. While originally, the term "BL" contrasted with "ML", or " muzzleloader " guns, after muzzleloaders were discontinued,

232-420: A cartridge case containing a reduced charge, and an attached star shell. British explosive shells filled with Lyddite were initially designated "common lyddite" and beginning in 1896 were the first British generation of modern "high explosive" shells. Lyddite is picric acid fused at 280 °F (138 °C) and allowed to solidify, producing a much denser dark-yellow form which is not affected by moisture and

290-461: A cloth bag, usually silk. The "stick" nature of cordite gave the cartridges a degree of rigidity and hence they retained a tubular shape and could be handled and loaded as a solid unit even without a case. With BL, cordite is contained in one or more cloth bags joined together. The complete unit is termed a cartridge. The empty bag was termed an "empty cartridge". Heavy naval guns may require up to four separate cartridges to be loaded, each consisting of

348-403: A full service charge for his gun, and cartridge Z to fire a star shell. Cartridges were sometimes made up of fractions of charges e.g. a 6-inch (152 mm) gun cartridge may be made up of two half charges or one two-fifths and one three-fifths laced together. A gun normally fired all rounds using the full charge, and varied the range by elevating or depressing the barrel. A howitzer gunner's job

406-492: A letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=F33&oldid=1154011101 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages HMS Somali (F33) HMS Somali

464-479: A single quadruple mount for the 40-millimetre (1.6 in) QF two-pounder Mk II "pom-pom" gun and two quadruple mounts for the 0.5-inch (12.7 mm) Mark III machine gun . Low-angle fire for the main guns was controlled by the director-control tower (DCT) on the bridge roof that fed data acquired by it and the 12-foot (3.7 m) rangefinder on the Mk II Rangefinder/Director directly aft of

522-402: A system by which multiple small metallic-cased charges were loaded and fired at the same time. Using multiple small fabric bags also allows the gunners to use a reduced charge if need be. The term "BLC" stood for "BL converted" and referred to a breech and breech mechanism modified from an early long-screw three- or four-motion to modern short-screw single-motion. An example is the conversion of

580-526: A total of 44,000 shaft horsepower (33,000  kW ) and gave a maximum speed of 36 knots (67 km/h; 41 mph). During her sea trials Somali made 36.5 knots (67.6 km/h; 42.0 mph) from 44,207 shp (32,965 kW) at a displacement of 2,014 long tons (2,046 t). The ships carried enough fuel oil to give them a range of 5,700 nautical miles (10,600 km; 6,600 mi) at 15 knots (28 km/h; 17 mph). The ships' complement consisted of 190 officers and ratings , although

638-417: Is above the deck. This allows for a lower profile for a turret , meaning that the turrets need not be superfiring (i.e. they can be mounted on the same deck and not obstruct each other at high angles of elevation). The term BL, in its general sense, stood for breech loading , and contrasted with muzzle loading. The shell was loaded via the breech (i.e. the gunner's end of the barrel, which opened) followed by

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696-562: Is assigned an effective full charge (EFC) value of "one*. Other round combinations are assigned lesser values derived from testing and experience. If a gun barrel is capable of firing three different round types: round A (EFC = 1); round B (EFC = 0.75); and round C (EFC = 0.25), and if 100 of each round type is fired, then the barrel is said to have fired (100×1.00) + (100×0.75) + (100×0.25) = 200 EFCs. If it had previously been determined from testing and experience that this type of barrel has an estimated wear life of 250 EFCs, this specific barrel

754-458: Is at about 80% of its useful life. Plans would be made to order a replacement barrel within the time an additional 50 EFCs were expected to be fired. However the actual decision to retire any specific barrel would be made on examination and measurement of actual wear rather than that predicted by the EFC count. In practice, a barrel might be replaced before reaching its EFC life, or the limits of wear. In

812-443: Is easier to detonate than the liquid form. Its French equivalent was "melinite", Japanese equivalent was " shimose ". Common lyddite shells "detonated" and fragmented into small pieces in all directions, with no incendiary effect. For maximum destructive effect the explosion needed to be delayed until the shell had penetrated its target. Early shells had walls of the same thickness for the whole length, later shells had walls thicker at

870-433: Is synonymous with " round ". For separate QF artillery, cartridge referred to the cartridge case, its primer, propellant charge, and the disposable lid and fastener of the case. In BL artillery terminology, cartridge referred to the propellant unit only – there was no case. British cartridges contained gunpowder until about 1892, and thereafter sticks of cordite bound together with an igniter pad, if necessary, in

928-505: Is usually equivalent full charge) Gun barrels naturally experience internal wear when fired, caused by mechanical wear from the projectile moving along the barrel, and thermal and chemical wear from propellant gases. This wear can reduce muzzle velocity and hence range, affect accuracy, produce unstable projectile flight, and, eventually, cause the gun barrel to fail. Most guns are capable of firing different types of ammunition with varying charges, and not all of these combinations produce

986-633: The Admiralty . On 3 September 1939, Somali intercepted the German freighter Hannah Böge , 350 miles south of Iceland, and took her as a prize. This was the first enemy merchant ship to be captured during the war. On 15 May 1940, during the Norwegian Campaign , Somali was carrying Brigadier the Hon. William Fraser , commander of 24th Guards Brigade , back to Harstad from a reconnaissance of Mo when she

1044-461: The BL 15-pounder to BLC 15-pounder . Calibre radius head: the radius of a circle with the curve of the shell's nose on its circumference, expressed in terms of the shell's calibre. The longer and more pointed (and hence streamlined) the shell's nose, the higher the C.R.H. Typical C.R.H. for British shells leading up to World War I was two: e.g. the curve of the nose of a two C.R.H. 6-inch (152 mm) shell

1102-571: The flotilla leaders carried an extra 20 officers and men consisting of the Captain (D) and his staff. The primary armament of the Tribal-class destroyers was eight quick-firing (QF) 4.7-inch (120 mm) Mark XII guns in four superfiring twin-gun mounts, one pair each fore and aft of the superstructure , designated 'A', 'B', 'X', and 'Y' from front to rear. The mounts had a maximum elevation of 40°. For anti-aircraft (AA) defence, they carried

1160-519: The 1936 Naval Estimates, Somali has been the only ship of her name to serve in the Royal Navy. The ship was ordered on 19 June 1936 from Swan Hunter & Wigham Richardson and was laid down on 27 August at the company's Wallsend , Tyne and Wear , shipyard . launched on 24 August 1937, Somali was completed on 7 December 1938 and commissioned five days later. The ship cost £ 340,095 which excluded weapons and communications outfits furnished by

1218-643: The DCT to an analogue mechanical computer , the Mk I Admiralty Fire Control Clock . Anti-aircraft fire for the main guns was controlled by the Rangefinder/Director which sent data to the mechanical Fuze Keeping Clock . The ships were fitted with a single above-water quadruple mount for 21-inch (533 mm) torpedoes. The Tribals were not intended as anti-submarine ships, but they were provided with ASDIC , one depth charge rack and two throwers for self-defence, although

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1276-945: The German weather ship München . Prior to being boarded, the crew of München threw overboard the ship's Enigma machine in a weighted bag. However, documents on the operation of the Enigma machine were left on board, as were vital codebooks providing a breakthrough for Allied codebreakers. On 13 August 1942, Somali rescued all 105 crew of the American cargo ship Almeria Lykes , which had been torpedoed by E boats while taking part in Operation Pedestal . The rescued crew were landed at Gibraltar . Lieutenant Commander Colin Maud took over as captain in September 1942 when her own captain, Jack Eaton,

1334-432: The base and thinning towards the nose. This was found to give greater strength and provide more space for explosive. Later shells had 4 c.r. heads , more pointed and hence streamlined than earlier 2 c.r.h. designs. Proper detonation of a lyddite shell would show black to grey smoke, or white from the steam of a water detonation. Yellow smoke indicated simple explosion rather than detonation, and failure to reliably detonate

1392-455: The case of the 15-inch (381 mm) guns fitted to the World War I Marshal Ney-class monitors a gun was generally condemned when wear reached about 0.74 in (19 mm) at 1 in (25 mm) from the start of the rifling. However it was the usual practice to replace guns when their projected remaining life fell below the ship's normal full outfit of ammunition per gun, which ensured that

1450-622: The common shell's nose fuze. The ogival two C.R.H. solid pointed nose was considered suitable for attacking shipping but was not armour-piercing - the main function was still explosive. They were of cast or forged (three- and six-pounder) steel and contained a gunpowder bursting charge slightly smaller than that of a common shell, a tradeoff for the longer heavier nose. In British service common pointed shells were typically painted black, except 12-pounder shells specific for QF guns which were painted lead colour to distinguish them from 12-pounder shells usable with both BL and QF guns. A red ring behind

1508-428: The correct dimensions but progressively weakened the case. Charge was a concept or category label rather than a specific item. It can be described as "the standard amount of propellant specified to carry out a particular purpose": For practical purposes, specific cartridges were specified for use to obtain the required charge. A gunner dealt with cartridges and would know that he could load (e.g.) cartridge X or Y for

1566-421: The entire magazine could be safely fired in action. This was the term for a gun together with its gun carriage , i.e. the complete set of equipment needed to be able to fire the gun, as the gun could only be fired when mounted on its correct carriage. The carriage could be a wheeled carriage, a static siege carriage or include both a traversing mounting and railway wagon in the case of a railway gun. For example,

1624-453: The explosive shell designation. Common lyddite shells in British service were painted yellow, with a red ring behind the nose to indicate the shell had been filled. For shellite, a successor of lyddite, see HE below. Common pointed shells, or CP were a type of common shell used in naval service from the 1890s to the 1910s which had a solid nose and a percussion fuze in the base rather than

1682-630: The firepower of the existing destroyer flotillas and were thus significantly larger and more heavily armed than the preceding I class . The ships displaced 1,891 long tons (1,921  t ) at standard load and 2,519 long tons (2,559 t) at deep load . They had an overall length of 377 feet (114.9 m), a beam of 36 feet 6 inches (11.13 m) and a draught of 11 feet 3 inches (3.43 m). The destroyers were powered by two Parsons geared steam turbines , each driving one propeller shaft using steam provided by three Admiralty three-drum boilers . The turbines developed

1740-402: The freezing water to save Lieutenant Commander Maud. Somali was the last Royal Navy Tribal-class destroyer to be sunk during the war. 69°11′N 15°32′W  /  69.183°N 15.533°W  / 69.183; -15.533 List of British ordnance terms#QF Between decks: applies to a naval gun mounting in which part of the rotating mass is below the deck, and part of it

1798-399: The general sense, but in the formal nomenclature it separated 6-inch (152 mm) guns with breeches designed for charges in brass cartridge cases for quick-firing QF from those designed for cloth bag charges for breech-loaders BL . Shells designed for one type were not necessarily suitable for use in the other type; for instance, a BL shell relied upon the tight fit of its driving band in

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1856-404: The gun bore to prevent it slipping back when the gun was elevated, but a QF shell could rely upon the cartridge case, either fixed or separate, to prevent it slipping back. This presented difficulties for BL guns at high angles. A special cartridge was developed for BL 9.2-inch (234 mm) guns on HA mountings, with provision for a wooden ( beech ) stick to be inserted through the centre to prevent

1914-454: The guns, the existing rangefinder/director was modified to accept a Type 285 gunnery radar as they became available. The number of depth charges was increased to 46 early in the war, and still more were added later. To increase the firing arcs of the AA guns, the rear funnel was shortened and the mainmast was reduced to a short pole mast. Authorized as one of nine Tribal-class destroyers under

1972-519: The interior of shells had to be varnished, the exterior had to be painted with leadless paint and the fuze-hole had to be made of a leadless alloy. Fuzes containing any lead could not be used with it. When World War I began Britain was replacing lyddite with modern "high explosive" (HE) such as TNT. After World War I the term "common lyddite" was dropped, and remaining stocks of lyddite-filled shells were referred to as HE (high explosive) shell filled lyddite. Hence "common" faded from use, replaced by "HE" as

2030-430: The late 1890s, but some stocks remained as late as 1914. In British service common shells were typically painted black with red bands behind the noses to indicate the shells were filled. Central pivot: was applied to a naval gun mounting that rotates around a central pivot that could be bolted to the deck without any structural alterations being required. The abbreviation cwt stands for hundredweight , which, despite

2088-611: The name, is equal to 112 pounds (51 kg), and signifies the weight of the gun barrel and breech. It is sometimes included in the name of a gun to differentiate it from other guns of the same calibre or weight of shot. For example, the QF 12-pounder 18 cwt naval gun is a different (and heavier) weapon than the QF 12-pounder 8-cwt Mk I naval gun , though they both fire shells of the same approximate weight (12 pounds (5.4 kg)). The director-control tower (DCT in British usage or "director" in US usage)

2146-497: The nose indicated the shell was filled. By World War II they were superseded in Royal Navy service by common pointed capped (CPC) and semi-armour piercing ( SAP ), filled with TNT. "Common shell" is a designation for early 19th century British explosive shells filled with "low explosives" such as "P mixture" (gunpowder) and usually had the fuzes located in the nose. Common shells on bursting (they did not "detonate") tended to break into relatively large fragments which continued along

2204-405: The propellant charge, and the breech mechanism was closed to seal the chamber. Breech loading, in its formal British ordnance sense, served to identify the gun as the type of rifled breechloading gun for which the powder charge was loaded in a silk or cloth bag and the breech mechanism was responsible for "obturation" i.e. sealing the chamber to prevent escape of the propellant gases. The term BL

2262-410: The propellant charge. Used with small arms and QF artillery ammunition. The QF cases in 1915 could be cleaned and then reloaded up to a maximum of six firings with Cordite charges, with the record detailing the "life of the case" marked on the base. The limitation on the number of firings was due to the case expanding on firing, having to be "rectified" by turning metal off the lower part, which restored

2320-399: The same firing damage per round fired. The concept of ‘effective full charge’ provides a means of estimating the remaining life of a gun barrel taking into account the varying charges that can be fired from it before it becomes so worn as to be unusable, or no longer safe. To illustrate, the round (i.e. the combination of projectile and propelling charge) that produces the most firing damage

2378-447: The shell slipping back on elevation. Although fixed ammunition allows for a rapid rate of fire in small to medium guns, BL is a better choice for heavy calibre guns; propellant was loaded in a number of small fabric bags, because a single bag holding the full charge would be far too big and bulky for the handlers to lift. Using fabric allows for the charge to be broken into small, easily handled units, while it would be difficult to design

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2436-557: The shell's trajectory rather than laterally. They had some incendiary effect. In the late 19th century "double common shells" were developed, lengthened so as to approach twice the standard shell weight, to carry more powder and hence increase explosive effect. They suffered from instability in flight and low velocity and were not widely used. As at 1914, common shells 6 inches (152 mm) and larger were of cast steel, smaller shells were of forged steel for service, and cast iron for practice. They were replaced by "common lyddite" shells by

2494-468: The standard 25-pound (11 kg) shell came ready-loaded with a red bag at the bottom containing the basic charge (charge one), together with white and blue bags laid lengthwise, as in a conventional gun charge, to make up the full service charge (charge three). The blue and white bags could be removed to provide progressively reduced charges (charge two and charge one). From 1944 one or two 4-ounce (110 g) "intermediate charge increments" could be added to

2552-469: The standard charge (replacing the blue bag) for high-angle fire and to provide greater control over angle of shell descent. For small arms or fixed QF ammunition, where the charge could not be varied by the gunner, the term charge was used to identify the Cordite propellant within the cartridge case, and the round as a whole was referred to as a full or reduced charge. E.g. an 18-pounder star round consisted of

2610-534: The term breech-loaders BL has applied exclusively to the type of breechloader introduced from 1880 onwards, using an interrupted-screw breeches. Early British Elswick breechloaders in the 1880s used a steel "cup" obturation method. This was quickly superseded in guns designed by the Royal Gun Factory by the French de Bange method, the basic principle of which is still in use today. In British service this became

2668-432: The term came to distinguish between traditional, non- obturating guns with fabric propellant bags and separately loaded shells , and quick-firing QF guns which used self-sealing brass cartridge cases, and which usually had the propellant and projectile fixed together as a unit for faster handling and loading. For instance, Britain before World War I had both QF and BL 6-inch (152 mm) guns. Both were "breech loading" in

2726-570: The throwers were not mounted in all ships; Twenty depth charges was the peacetime allotment, but this increased to 30 during wartime. Heavy losses to German air attack during the Norwegian Campaign demonstrated the ineffectiveness of the Tribals' anti-aircraft suite and the RN decided in May 1940 to replace 'X' mount with two QF 4-inch (102 mm) Mark XVI dual-purpose guns in a twin-gun mount. To better control

2784-620: Was a Tribal-class destroyer of the British Royal Navy that saw service in World War II . She was launched in 1937, captured the first prize of World War II and served in Home and Mediterranean waters. She was torpedoed on 20 September 1942 in the Arctic and foundered five days later while under tow. The Tribals were intended to counter the large destroyers being built abroad and to improve

2842-439: Was a feature of naval ships. It was a trainable turret incorporating the gun-laying sights and often a rangefinder . From here the gunnery officer could select targets and take the range, bearing and rates of change. This data would be provided to the transmitting station (TS), where a firing solution would be calculated and passed on to the gun turrets as the correct degree of training and elevation. (Note: The British Army term

2900-453: Was a problem with lyddite, especially in its earlier usage. To improve the detonation "exploders" with a small quantity of picric powder or even of TNT (in smaller diameter shells, such as in 3-pounder and 12-pounder guns) was loaded between the fuze and the main lyddite filling or in a thin tube running through most of the shell's length. Lyddite presented a major safety problem because it reacted dangerously with metal bases. This required that

2958-626: Was bombed by German aircraft and forced to return to the United Kingdom for repairs, taking the Brigadier with her. He did not reach Harstad until 23 May. On 23 October, Matabele , Punjabi and Somali shelled and sank WBS 5 Adolf Vinnen in the Norwegian Sea off Stadlandet , Norway. Somali was the leader of the 6th Destroyer Flotilla and spent most of the winter of 1940–41 screening Home Fleet sweeps. In May 1941, Somali boarded

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3016-400: Was designed so that one or more rings could be quickly removed and discarded before loading, hence providing progressively smaller charges. E.g. if the gunner on a QF 4.5-inch howitzer was ordered to load charge four, he would know he had to remove the top ring from the cartridge, leaving four rings; for charge three he would remove two rings. Discarded rings were burned after the action. This

3074-410: Was equivalent to the curve of a circle with a radius of 12 inches (300 mm). Shells of four C.R.H. were soon developed in World War I, identified by an A following the shell mark number, B for six, and so on. For modern streamlined shells post-World War I, two numbers were necessary to more correctly denote a shell's C.R.H. characteristics. For instance, the World War I 6-inch 26 cwt howitzer shell

3132-528: Was first used to refer to the Armstrong breechloaders , introduced in 1859. Following the discontinuation of Armstrong breechloaders and the period of British rifled muzzle-loaders RML , British breechloaders were re-introduced in 1880. At this point the term rifled breech-loaders RBL was retrospectively introduced to refer to the Armstrong breechloaders, which had a totally different breech mechanism, and since then

3190-625: Was ill. On 20 September 1942 Somali was torpedoed by U-703 while covering Convoy QP 14 during the Russian convoys. She was hit in her engine room, and although taken under tow by the destroyer Ashanti , she sank on 25 September, after heavy weather broke her back. Of the 102 men on board, only 35 were rescued from the Arctic waters. Leading Seaman Goad of Ashanti was awarded the Albert Medal for "great bravery in saving life at sea" after diving into

3248-411: Was more complicated because the range table would specify different "charges", or fractions of the full service charge, for different ranges and angles of shell descent. The standard cartridge for his gun, which as a whole made up the full service charge, would consist of a central "mushroom" cordite core and several smaller cordite rings in bags stacked around the core like doughnuts, all tied together. It

3306-512: Was the standard procedure for howitzers up to and including World War II. In World War II a different system was introduced for varying charges for the QF 25 pounder gun-howitzer , which used separate-loading QF ammunition. A separate 2.7-pound (1.2 kg) "super charge" cartridge was available for firing the 20-pound (9.1 kg) high-velocity anti-tank AP shot, and an additional 4.5-ounce (130 g) "super charge increment" could be added to that for even higher velocity. The cartridge for firing

3364-515: Was two C.R.H., and the World War II Mk 2D shell was referred to as "5/10 C.R.H.". "Cartridge" in British ammunition terminology typically refers to the physical object containing the propellant that a gunner loads. For small arms and fixed QF artillery ammunition, e.g., the .303 or 18-pounder respectively, this denoted the complete round, that is, the cartridge case, percussion cap or primer, propellant charge and projectile. In this use it

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