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91-408: The D-56T is an anti-tank gun of 76.2mm calibre. It can fire five types of rounds, using a manual loader system, it has an effective fire rate of six to eight rounds per minute. It has a max effective range of approximately 1500 meters. This gun is 42 calibers long. A typical combat ammunition load consists of 24 x OF-350 Frag-HE, 4 x sub-caliber AP-T, 4 x AP-T and 8 x BK-350M HEAT rounds. The gun

182-474: A "shell" as opposed to "shot". By the time of the Second World War, AP shells with a bursting charge were sometimes distinguished by appending the suffix "HE". At the beginning of the war, APHE was common in anti-tank shells of 75 mm caliber and larger due to the similarity with the much larger naval armour piercing shells already in common use. As the war progressed, ordnance design evolved so that

273-536: A 1543 English mortar shell was filled with "wildfire." By the 18th century, it was known that if loaded toward the muzzle instead, the fuse could be lit by the flash through the windage between the shell and the barrel. At about this time, shells began to be employed for horizontal fire from howitzers with a small propelling charge and, in 1779, experiments demonstrated that they could be used from guns with heavier charges. The use of exploding shells from field artillery became relatively commonplace from early in

364-459: A bastion of the Bavarian city of Ingolstadt , Germany . Many of the grenades contained their original black-powder loads and igniters. Most probably the grenades were intentionally dumped in the moat of the bastion before the year 1723. An early problem was that there was no means of precisely measuring the time to detonation – reliable fuses did not yet exist, and the burning time of

455-526: A better effect. This guideline was achieved by the 1960s with the 155 mm L15 shell, developed as part of the German-British FH-70 program. The key requirement for increasing the HE content without increasing shell weight was to reduce the thickness of shell walls, which required improvements in high tensile steel. The most common shell type is high explosive , commonly referred to simply as HE. They have

546-503: A bore able to withstand many firings before needing refurbishment. In World War I 45-caliber naval gun barrels were typical, in World War II 50- to 55-caliber barrels were common, with Germany already manufacturing tank guns of 70 calibers by 1943. Today, 60- to 70-caliber barrels are not uncommon, but the latest technology has allowed shorter barrels of 55 calibers to attain muzzle velocities of 1,750 m/s (5,700 ft/s), as with

637-401: A cartridge case and it achieves obturation through a screw breech instead of a sliding block. Sometimes when reading about artillery the term separate loading ammunition will be used without clarification of whether a cartridge case is used or not, in which case it refers to the type of breech used. Heavy artillery pieces and naval artillery tend to use bagged charges and projectiles because

728-490: A challenge because there was no way of ensuring that the impact mechanism contacted the target. Therefore, ball shells needed a time fuse that was ignited before or during firing and burned until the shell reached its target. Cast iron shells packed with gunpowder have been used in warfare since at least early 13th century China. Hollow, gunpowder-packed shells made of cast iron used during the Song dynasty (960-1279) are described in

819-459: A concrete demolition 203 mm (8 in) shell 146 kg (322 lbs), a 280 mm (11 in) battleship shell about 300 kg (661 lbs), and a 460 mm (18 in) battleship shell over 1,500 kg (3,307 lbs). The Schwerer Gustav large-calibre gun fired shells that weighed between 4,800 kg (10,582 lbs) and 7,100 kg (15,653 lbs). During the 19th century, the British adopted

910-412: A fixed round becomes too long or too heavy to load by a gun crew. Another issue is the inability to vary propellant charges to achieve different velocities and ranges. Lastly, there is the issue of resource usage since a fixed round uses a case, which can be an issue in a prolonged war if there are metal shortages. Separate loading cased charge ammunition has three main components: the fuzed projectile,

1001-440: A forward bourrelet section machined to a diameter slightly smaller than the original land-to-land dimension of the barrel and a copper driving band somewhat larger than the groove-to-groove diameter to effectively seal the bore as it becomes enlarged by erosion during prolonged firing. United States Navy guns typically used rifling depth between one-half and one percent of caliber. Projectile bourrelet diameter specification

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1092-412: A half-inch. The sabot was also intended to reduce jamming during loading. Despite the use of exploding shells, the use of smoothbore cannons firing spherical projectiles of shot remained the dominant artillery method until the 1850s. The mid–19th century saw a revolution in artillery, with the introduction of the first practical rifled breech loading weapons. The new methods resulted in the reshaping of

1183-408: A higher velocity without placing undue strain on the gun. In internal ballistics terms, if the base of a projectile is thought of as a piston propelled by the expanding gas, then as barrel length increases the volume swept by the piston also increases, and hence the amount of energy that can be extracted from the gas's burning increases. A longer barrel allows more propellant to be used: the propellant

1274-695: A huge cloud of smoke and concealed shooters were given away by a cloud of smoke over the firing position. Guncotton , a nitrocellulose-based material, was discovered by Swiss chemist Christian Friedrich Schönbein in 1846. He promoted its use as a blasting explosive and sold manufacturing rights to the Austrian Empire . Guncotton was more powerful than gunpowder, but at the same time was somewhat more unstable. John Taylor obtained an English patent for guncotton; and John Hall & Sons began manufacture in Faversham . British interest waned after an explosion destroyed

1365-409: A particular form of designating artillery. Field guns were designated by nominal standard projectile weight, while howitzers were designated by barrel caliber. British guns and their ammunition were designated in pounds , e.g., as "two-pounder" shortened to "2-pr" or "2-pdr". Usually, this referred to the actual weight of the standard projectile (shot, shrapnel, or high explosive), but, confusingly, this

1456-419: A small rocket motor built into its base to provide additional thrust. The second has a pyrotechnic device in its base that bleeds gas to fill the partial vacuum created behind the shell and hence reduce base-drag. These shell designs usually have reduced high-explosive filling to remain within the permitted mass for the projectile, and hence less lethality. The caliber of a shell is its diameter . Depending on

1547-482: A strong steel case, a bursting charge, and a fuse . The fuse detonates the bursting charge which shatters the case and scatters hot, sharp case pieces ( fragments , splinters ) at high velocity. Most of the damage to soft targets, such as unprotected personnel, is caused by shell pieces rather than by the blast. The term "shrapnel" is sometimes used to describe the shell pieces, but shrapnel shells functioned very differently and are long obsolete. The speed of fragments

1638-435: A tapered boat tail ; but some specialized types differ widely. Gunpowder is a low explosive , meaning it will not create a concussive, brisant explosion unless it is contained, as in a modern-day pipe bomb or pressure cooker bomb . Early grenades were hollow cast-iron balls filled with gunpowder, and "shells" were similar devices designed to be shot from artillery in place of solid cannonballs ("shot"). Metonymically ,

1729-469: A thickness about 1/15th of the total diameter and filled with powder, saltpeter, pitch, coal and tallow. They were used to 'suffocate or expel the enemy in casemates, mines or between decks; for concealing operations; and as signals. During the First World War , shrapnel shells and explosive shells inflicted terrible casualties on infantry, accounting for nearly 70% of all war casualties and leading to

1820-421: A weapon had to perform, without fail. There was no ready replacement, nor one that could be readily supplied. Over time, the terms of pound (weight of shell ) and bore (the actual bore of the weapon) became confused and blurred. Eventually, when the technology existed, the bore (in inches or millimetres) came to be the standard measure. For naval rifles, the initial change was to actual bore, thus facilitating

1911-455: Is semi-fixed ammunition. With semi-fixed ammunition the round comes as a complete package but the projectile and its case can be separated. The case holds a set number of bagged charges and the gun crew can add or subtract propellant to change range and velocity. The round is then reassembled, loaded, and fired. Advantages include easier handling for larger caliber rounds, while range and velocity can easily be varied by increasing or decreasing

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2002-414: Is all burned fairly early in the projectile's journey along the barrel, except in the very common instance where combustion is still occurring as the projectile leaves the muzzle and a visible muzzle "flash" is produced. The projectile continues to accelerate as long as the pressure behind it is sufficient to overcome bore friction. The excess energy will continue to accelerate the projectile until it exits

2093-404: Is generally most suitable but cupronickel or gilding metal were also used. Although an early percussion fuze appeared in 1650 that used a flint to create sparks to ignite the powder, the shell had to fall in a particular way for this to work and this did not work with spherical projectiles. An additional problem was finding a suitably stable "percussion powder". Progress was not possible until

2184-443: Is obsolete. Typically, the thickness of the metal body was about a sixth of their diameter, and they were about two-thirds the weight of solid shot of the same caliber. To ensure that shells were loaded with their fuses toward the muzzle, they were attached to wooden bottoms called sabots . In 1819, a committee of British artillery officers recognized that they were essential stores and in 1830 Britain standardized sabot thickness as

2275-504: Is typically fitted with the D-56T gun with a two-plane gun stabiliser , a double-baffle muzzle brake and a bore evacuator towards the muzzle. The D-56T usually saw itself firing five types of anti-tank rounds. Most rounds that were used on the D-56T were HE rounds, with usually a ready combat load having 24 pieces of OF-350 High Explosive Fragmentation ammunition, and 16 other pieces, with three other types of rounds. Common ammunition types were

2366-454: Is usually mounted in an oval dish-type circular truncated cone turret with flat sloping sides which is mounted over the second, third, and fourth pair of road wheels. All PT-76s have a fume extractor for the main gun at the rear of the turret. Some were fitted with a multi-slotted muzzle brake . Most PT-76s typically feature this gun with a double-baffle muzzle brake, except for the PT-76B, which

2457-751: The Industrial Revolution that Armstrong was able to construct a viable solution. Another innovative feature was what Armstrong called its "grip", which was essentially a squeeze bore ; the 6 inches of the bore at the muzzle end was of slightly smaller diameter, which centered the shell before it left the barrel and at the same time slightly swaged down its lead coating, reducing its diameter and slightly improving its ballistic qualities. Rifled guns were also developed elsewhere – by Major Giovanni Cavalli and Baron Martin von Wahrendorff in Sweden, Krupp in Germany and

2548-524: The Panzer V tank is described as a "75 mm L/70," meaning a barrel with an internal bore of 75 mm (3.0 in), and 5,250 mm (17 ft 3 in) long. The bore to barrel length ratio is called "caliber" in naval gunnery, but is called "length" in army artillery. Before World War II, the US Navy used 5"/51 caliber (5" L/51) as surface-to-surface guns and 5"/25 caliber (5" L/25) as surface to air guns. By

2639-577: The Republic of Venice at Jadra in 1376. Shells with fuses were used at the 1421 siege of St Boniface in Corsica . These were two hollowed hemispheres of stone or bronze held together by an iron hoop. At least since the 16th century grenades made of ceramics or glass were in use in Central Europe. A hoard of several hundred ceramic grenades dated to the 17th century was discovered during building works in front of

2730-497: The Rheinmetall 120 mm tank gun . However, by using discarding sabots , many such guns fire projectiles which are much smaller than the gun bore, so the relationship of projectile size to barrel length is not as straightforward as with older ordnance. Shell (projectile) A shell , in a modern military context, is a projectile whose payload contains an explosive , incendiary , or other chemical filling. Originally it

2821-455: The Royal Arsenal at Woolwich . The piece was rifled , which allowed for a much more accurate and powerful action. Although rifling had been tried on small arms since the 15th century, the necessary machinery to accurately rifle artillery only became available in the mid-19th century. Martin von Wahrendorff and Joseph Whitworth independently produced rifled cannons in the 1840s, but it

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2912-569: The Wiard gun in the United States. However, rifled barrels required some means of engaging the shell with the rifling. Lead coated shells were used with the Armstrong gun , but were not satisfactory so studded projectiles were adopted. However, these did not seal the gap between shell and barrel. Wads at the shell base were also tried without success. In 1878, the British adopted a copper " gas-check " at

3003-604: The fuzed projectile, the casing to hold the propellants and primer , and the single propellant charge. Everything is included in a ready-to-use package and in British ordnance terms is called fixed quick firing . Often guns which use fixed ammunition use sliding-block or sliding-wedge breeches and the case provides obturation which seals the breech of the gun and prevents propellant gasses from escaping. Sliding block breeches can be horizontal or vertical. Advantages of fixed ammunition are simplicity, safety, moisture resistance and speed of loading. Disadvantages are eventually

3094-489: The "pressure curve" further down the bore. By exposing the projectile base to a given pressure for a longer length of time, velocity can be increased without elevating the pressure level generated. Technological improvements had made it possible to introduce into use long gun barrels that are strong enough to withstand the forces involved in accelerating the shell to a high velocity, while remaining light enough to be reasonably mobile, rigid enough to maintain accuracy, and having

3185-490: The 17th century onwards. The British adopted parachute lightballs in 1866 for 10-, 8- and 5 1 ⁄ 2 -inch calibers. The 10-inch was not officially declared obsolete until 1920. Smoke balls also date back to the 17th century, British ones contained a mix of saltpetre, coal, pitch, tar, resin, sawdust, crude antimony and sulphur. They produced a "noisome smoke in abundance that is impossible to bear". In 19th-century British service, they were made of concentric paper with

3276-436: The 19th century. Until the mid 19th century, shells remained as simple exploding spheres that used gunpowder, set off by a slow burning fuse. They were usually made of cast iron , but bronze , lead , brass and even glass shell casings were experimented with. The word bomb encompassed them at the time, as heard in the lyrics of The Star-Spangled Banner ("the bombs bursting in air"), although today that sense of bomb

3367-538: The Austrian factories blew up in 1862, Thomas Prentice & Company began manufacturing guncotton in Stowmarket in 1863; and British War Office chemist Sir Frederick Abel began thorough research at Waltham Abbey Royal Gunpowder Mills leading to a manufacturing process that eliminated the impurities in nitrocellulose making it safer to produce and a stable product safer to handle. Abel patented this process in 1865, when

3458-419: The Faversham factory in 1847. Austrian Baron Wilhelm Lenk von Wolfsberg built two guncotton plants producing artillery propellant, but it was dangerous under field conditions, and guns that could fire thousands of rounds using gunpowder would reach their service life after only a few hundred shots with the more powerful guncotton. Small arms could not withstand the pressures generated by guncotton. After one of

3549-564: The First World War (such as the BL 60-pounder gun , RML 2.5 inch Mountain Gun , 4 inch gun, 4.5 inch howitzer) through to the end of World War II (5.5 inch medium gun, 25-pounder gun-howitzer , 17-pounder tank gun), but the majority of naval guns were by caliber. After the end of World War II, field guns were designated by caliber. There are many different types of shells. The principal ones include: With

3640-750: The German super- railway guns , Gustav and Dora , which were 800 mm (31.5 in) in caliber. Very large shells have been replaced by rockets , missiles , and bombs . Today the largest shells in common use are 155 mm (6.1 in). Gun calibers have standardized around a few common sizes, especially in the larger range, mainly due to the uniformity required for efficient military logistics. Shells of 105 and 155 mm for artillery with 105 and 120 mm for tank guns are common in NATO allied countries. Shells of 122, 130, and 152 mm for artillery with 100, 115, and 125 mm for tank guns, remain in common usage among

3731-631: The OF-350 Frag-HE, BM-354P HVAP-T and the BK-354M HEAT-FS. Background: Tank gun , List of tank guns This article relating to artillery is a stub . You can help Misplaced Pages by expanding it . Caliber (artillery) In artillery , caliber or calibre is the internal diameter of a gun barrel, or, by extension, a relative measure of the barrel length. Rifled barrels introduce ambiguity to measurement of caliber. A rifled bore consists of alternating grooves and lands. The distance across

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3822-544: The Royal Artillery was adopted by the army. It was a wooden fuze about 6 inches long and used shear wire to hold blocks between the fuze magazine and a burning match. The match was ignited by propellant flash and the shear wire broke on impact. A British naval percussion fuze made of metal did not appear until 1861. Gunpowder was used as the only form of explosive up until the end of the 19th century. Guns using black powder ammunition would have their view obscured by

3913-454: The adoption of steel combat helmets on both sides. Frequent problems with shells led to many military disasters with dud shells, most notably during the 1916 Battle of the Somme . Shells filled with poison gas were used from 1917 onwards. Artillery shells are differentiated by how the shell is loaded and propelled, and the type of breech mechanism. Fixed ammunition has three main components:

4004-446: The barrel (from breech to muzzle ) is divided by the barrel diameter to give a dimensionless quantity. For example, the main guns of the Iowa -class battleships can be referred to as 16"/50 caliber. They are 16   inches in diameter and the barrel is 800   inches long (16 × 50 = 800). This is also sometimes indicated using the prefix L/; so for example, the most common gun for

4095-494: The base of their studded projectiles and in 1879 tried a rotating gas check to replace the studs, leading to the 1881 automatic gas-check. This was soon followed by the Vavaseur copper driving band as part of the projectile. The driving band rotated the projectile, centered it in the bore and prevented gas escaping forwards. A driving band has to be soft but tough enough to prevent stripping by rotational and engraving stresses. Copper

4186-441: The bore from groove to groove is greater than the distance from land to land. Projectiles fired from rifled barrels must be of the full groove-to-groove diameter to be effectively rotated by the rifling, but the caliber has sometimes been specified as the land-to-land diameter before rifling grooves were cut. The depth of rifling grooves (and the consequent ambiguity) increases in larger calibers. Steel artillery projectiles may have

4277-538: The bursting charges in APHE became ever smaller to non-existent, especially in smaller caliber shells, e.g. Panzergranate 39 with only 0.2% HE filling. Although smokeless powders were used as a propellant, they could not be used as the substance for the explosive warhead, because shock sensitivity sometimes caused detonation in the artillery barrel at the time of firing. Picric acid was the first high-explosive nitrated organic compound widely considered suitable to withstand

4368-559: The casing to hold the propellants and primer, and the bagged propellant charges. The components are usually separated into two or more parts. In British ordnance terms, this type of ammunition is called separate quick firing . Often guns which use separate loading cased charge ammunition use sliding-block or sliding-wedge breeches and during World War I and World War II Germany predominantly used fixed or separate loading cased charges and sliding block breeches even for their largest guns. A variant of separate loading cased charge ammunition

4459-532: The combustion temperature and hence erosion and barrel wear. Cordite could be made to burn more slowly which reduced maximum pressure in the chamber (hence lighter breeches, etc.), but longer high pressure – significant improvements over gunpowder. Cordite could be made in any desired shape or size. The creation of cordite led to a lengthy court battle between Nobel, Maxim, and another inventor over alleged British patent infringement. A variety of fillings have been used in shells throughout history. An incendiary shell

4550-434: The curve was a segment of a circle having a radius of twice the shell caliber. After that war, ogive shapes became more complex and elongated. From the 1960s, higher quality steels were introduced by some countries for their HE shells, this enabled thinner shell walls with less weight of metal and hence a greater weight of explosive. Ogives were further elongated to improve their ballistic performance. Advances in metallurgy in

4641-477: The discovery of mercury fulminate in 1800, leading to priming mixtures for small arms patented by the Rev Alexander Forsyth , and the copper percussion cap in 1818. The percussion fuze was adopted by Britain in 1842. Many designs were jointly examined by the army and navy, but were unsatisfactory, probably because of the safety and arming features. However, in 1846 the design by Quartermaster Freeburn of

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4732-524: The early Ming Dynasty Chinese military manual Huolongjing , written in the mid 14th century. The History of Jin 《金史》 (compiled by 1345) states that in 1232, as the Mongol general Subutai (1176–1248) descended on the Jin stronghold of Kaifeng , the defenders had a " thunder crash bomb " which "consisted of gunpowder put into an iron container ... then when the fuse was lit (and the projectile shot off) there

4823-448: The end of World War II, the dual purpose 5-inch/38-caliber gun (5" L/38) was standard naval armament against surface and air targets. All three had a bore diameter of 5   inches (not 5.51 or 5.25 or 5.38 as often misread). Naval rifles, although constructed and manufactured in roughly the same manners as land-based artillery, were built to much more stringent and studious standards than land-based weapons, and for good reason. At sea,

4914-538: The first being Germany and Austria which introduced new weapons in 1888. Subsequently, Poudre B was modified several times with various compounds being added and removed. Krupp began adding diphenylamine as a stabilizer in 1888. Britain conducted trials on all the various types of propellant brought to their attention, but were dissatisfied with them all and sought something superior to all existing types. In 1889, Sir Frederick Abel , James Dewar and W. Kellner patented (No. 5614 and No. 11,664 in

5005-468: The gas has to fill. In order to achieve maximum muzzle velocity with the shortest barrel length, the projectile should exit the barrel as the gas pressure reduces to a small fraction of the maximum, although unlike maximum chamber pressure, the small fraction desired is impossible to measure. In modern guns, increased muzzle velocities can be produced by altering powder composition and/or using duplex charges containing two different powders in order to extend

5096-491: The greatest naval shell ever deployed in combat . Early gun barrels were short and thick, typically no more than 26 calibers, as the gunpowder propellant they used burned very quickly and violently, and hence its acceleration time was short. Slower-burning " brown powder " formulations of gunpowder allowed gun barrel length to increase slightly in the 1880s, but enormous quantities of brown powder were required. New slower-burning " smokeless powder " propellants available from

5187-428: The gun to achieve greater range and accuracy than existing smooth-bore muzzle-loaders with a smaller powder charge. The gun was also a breech-loader. Although attempts at breech-loading mechanisms had been made since medieval times, the essential engineering problem was that the mechanism could not withstand the explosive charge. It was only with the advances in metallurgy and precision engineering capabilities during

5278-436: The historical period and national preferences, this may be specified in millimeters , centimeters , or inches . The length of gun barrels for large cartridges and shells (naval) is frequently quoted in terms of the ratio of the barrel length to the bore size, also called caliber . For example, the 16"/50 caliber Mark 7 gun is 50 calibers long, that is, 16"×50=800"=66.7 feet long. Some guns, mainly British, were specified by

5369-604: The industrial era allowed for the construction of rifled breech-loading guns that could fire at a much greater muzzle velocity . After the British artillery was shown up in the Crimean War as having barely changed since the Napoleonic Wars , the industrialist William Armstrong was awarded a contract by the government to design a new piece of artillery. Production started in 1855 at the Elswick Ordnance Company and

5460-410: The introduction of the first ironclads in the 1850s and 1860s, it became clear that shells had to be designed to effectively pierce the ship armour. A series of British tests in 1863 demonstrated that the way forward lay with high-velocity lighter shells. The first pointed armour-piercing shell was introduced by Major Palliser in 1863. Approved in 1867, Palliser shot and shell was an improvement over

5551-430: The manufacture of standard projectiles. They then began to measure the effective length (and therefore range) of the weapon in calibers. These are a measure of the standardized length of the barrel versus the rifled bore of the barrel. In other words, a 12/45 is 12"×45= the length of the rifled bore of that gun in inches. This explains the differences in both penetration and long range performance of various naval rifles over

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5642-405: The mid-1880s onwards, such as Poudre B , cordite and nitrocellulose allowed a gentler prolonged acceleration, hence gun barrels were made progressively longer and thinner. The new formulations were far more powerful propellants than gunpowder and far less was needed by weight as they transformed almost entirely to gases when burned. Muzzle velocity became limited only by the length of barrel that

5733-497: The multi-seeded fruit resembles the powder-filled, fragmentizing bomb. Words cognate with grenade are still used for an artillery or mortar projectile in some European languages. Shells are usually large-caliber projectiles fired by artillery, armoured fighting vehicles (e.g. tanks , assault guns , and mortar carriers ), warships , and autocannons . The shape is usually a cylinder topped by an ogive -tipped nose cone for good aerodynamic performance , and possibly with

5824-409: The muzzle. If the pressure behind the projectile drops sufficiently before the projectile exits the bore, the projectile can and will slow while still within the barrel, despite residual bore pressure behind the projectile. A light charge with insufficient pressure to expel the projectile will result in a "squib", or projectile lodged in the bore. This pressure is reduced by the increasing barrel volume

5915-478: The name Lyddite . Japan followed with an "improved" formula known as shimose powder . In 1889, a similar material, a mixture of ammonium cresylate with trinitrocresol, or an ammonium salt of trinitrocresol, started to be manufactured under the name ecrasite in Austria-Hungary . By 1894, Russia was manufacturing artillery shells filled with picric acid. Ammonium picrate (known as Dunnite or explosive D )

6006-476: The names of Abel and Dewar) a new formulation that was manufactured at the Royal Gunpowder Factory at Waltham Abbey. It entered British service in 1891 as Cordite Mark 1. Its main composition was 58% nitro-glycerine, 37% guncotton and 3% mineral jelly. A modified version, Cordite MD, entered service in 1901, this increased guncotton to 65% and reduced nitro-glycerine to 30%, this change reduced

6097-421: The need for a pressure-holding casing, so the casing of later shells only needs to contain the munition, and, if desired, to produce shrapnel. The term "shell," however, was sufficiently established that it remained as the term for such munitions. Hollow shells filled with gunpowder needed a fuse that was either impact triggered ( percussion ) or time delayed. Percussion fuses with a spherical projectile presented

6188-470: The number of propellant charges. Disadvantages include more complexity, slower loading, less safety, less moisture resistance, and the metal cases can still be a material resource issue. In separate loading bagged charge ammunition there are three main components: the fuzed projectile, the bagged charges and the primer. Like separate loading cased charge ammunition, the number of propellant charges can be varied. However, this style of ammunition does not use

6279-460: The ordinary elongated shot of the time. Palliser shot was made of cast iron , the head being chilled in casting to harden it, using composite molds with a metal, water cooled portion for the head. Britain also deployed Palliser shells in the 1870s–1880s. In the shell, the cavity was slightly larger than in the shot and was filled with 1.5% gunpowder instead of being empty, to provide a small explosive effect after penetrating armour plating. The shell

6370-402: The powder fuse was subject to considerable trial and error. Early powder-burning fuses had to be loaded fuse down to be ignited by firing or a portfire or slow match put down the barrel to light the fuse. Other shells were wrapped in bitumen cloth, which would ignite during the firing and in turn ignite a powder fuse. Nevertheless, shells came into regular use in the 16th century, for example,

6461-432: The regions of Eastern Europe, Western Asia, Northern Africa, and Eastern Asia. Most common calibers have been in use for many decades, since it is logistically complex to change the caliber of all guns and ammunition stores. The weight of shells increases by and large with caliber. A typical 155 mm (6.1 in) shell weighs about 50 kg (110 lbs), a common 203 mm (8 in) shell about 100 kg (220 lbs),

6552-485: The rifle itself and also altering the breech, allowed a 1,400 lb (640 kg) projectile and, overall, a greater barrel life. Again we see this pattern with the US 16" guns. The initial design was 45 calibers in length and fired a 2,200 lb (1,000 kg) shell. The later re-design to 50 calibre not only allowed a higher velocity, but also a heavier 2,700 lb (1,200 kg) shell, which ultimately came to be accepted as

6643-501: The second Austrian guncotton factory exploded. After the Stowmarket factory exploded in 1871, Waltham Abbey began production of guncotton for torpedo and mine warheads. In 1884, Paul Vieille invented a smokeless powder called Poudre B (short for poudre blanche —white powder, as distinguished from black powder ) made from 68.2% insoluble nitrocellulose , 29.8% soluble nitrocellusose gelatinized with ether and 2% paraffin. This

6734-507: The shock of firing in conventional artillery . In 1885, based on research of Hermann Sprengel, French chemist Eugène Turpin patented the use of pressed and cast picric acid in blasting charges and artillery shells . In 1887, the French government adopted a mixture of picric acid and guncotton under the name Melinite . In 1888, Britain started manufacturing a very similar mixture in Lydd , Kent, under

6825-476: The spherical shell into its modern recognizable cylindro-conoidal form. This shape greatly improved the in-flight stability of the projectile and meant that the primitive time fuzes could be replaced with the percussion fuze situated in the nose of the shell. The new shape also meant that further, armour-piercing designs could be used. During the 20th century, shells became increasingly streamlined. In World War I, ogives were typically two circular radius head (crh) –

6916-418: The term "shell", from the casing, came to mean the entire munition . In a gunpowder-based shell, the casing was intrinsic to generating the explosion, and thus had to be strong and thick. Its fragments could do considerable damage, but each shell broke into only a few large pieces. Further developments led to shells which would fragment into smaller pieces. The advent of high explosives such as TNT removed

7007-528: The weight and size of the projectiles and propelling charges can be more than a gun crew can manage. Advantages include easier handling for large rounds, decreased metal usage, while range and velocity can be varied by using more or fewer propellant charges. Disadvantages include more complexity, slower loading, less safety and less moisture resistance. Extended-range shells are sometimes used. These special shell designs may be rocket-assisted projectiles (RAP) or base bleed (BB) to increase range. The first has

7098-462: The weight of their shells (see below). Explosive rounds as small as 12.7 x 82 mm and 13 x 64 mm have been used on aircraft and armoured vehicles, but their small explosive yields have led some nations to limit their explosive rounds to 20mm (.78 in) or larger. International Law precludes the use of explosive ammunition for use against individual persons, but not against vehicles and aircraft. The largest shells ever fired during war were those from

7189-510: The years. In addition to the possible improvements in overall performance (i.e. muzzle velocity and striking force), the increase in barrel length also allowed, in some circumstances, an increase in projectile size as well. For example, the American 14/45, as introduced in the New York -class battleships, fired a 1,250 lb (570 kg) projectile. Later improvements to the design, lengthening

7280-445: Was 0.015 inches (0.38 mm) less than land-to-land diameter with a minus manufacturing tolerance, so average clearance was about 0.012 inches (0.30 mm). Driving band diameter was groove-to-groove diameter plus 0.02 inches (0.51 mm). The length of the barrel (especially for larger guns) is often quoted in multiples of the caliber, used, for example, in US naval rifles 3 in (76 mm) or larger. The effective length of

7371-523: Was Armstrong's gun that was first to see widespread use during the Crimean War. The cast iron shell of the Armstrong gun was similar in shape to a Minié ball and had a thin lead coating which made it fractionally larger than the gun's bore and which engaged with the gun's rifling grooves to impart spin to the shell. This spin, together with the elimination of windage as a result of the tight fit, enabled

7462-407: Was a great explosion the noise whereof was like thunder, audible for more than thirty miles, and the vegetation was scorched and blasted by the heat over an area of more than half a mou . When hit, even iron armour was quite pierced through." Archeological examples of these shells from the 13th century Mongol invasions of Japan have been recovered from a shipwreck. Shells were used in combat by

7553-460: Was adopted for the Lebel rifle. Vieille's powder revolutionized the effectiveness of small guns, because it gave off almost no smoke and was three times more powerful than black powder. Higher muzzle velocity meant a flatter trajectory and less wind drift and bullet drop, making 1000 meter shots practicable. Other European countries swiftly followed and started using their own versions of Poudre B,

7644-447: Was called a bombshell , contrasting with solid shells used for early rifled artillery, but "shell" has come to be unambiguous in a military context. A shell can hold a tracer . All explosive- and incendiary-filled projectiles, particularly for mortars , were originally called grenades , derived from the French word for pomegranate , so called because of the similarity of shape and that

7735-540: Was correspondingly slightly longer than the shot to compensate for the lighter cavity. The powder filling was ignited by the shock of impact and hence did not require a fuze. However, ship armour rapidly improved during the 1880s and 1890s, and it was realised that explosive shells with steel had advantages including better fragmentation and resistance to the stresses of firing. These were cast and forged steel. AP shells containing an explosive filling were initially distinguished from their non-HE counterparts by being called

7826-428: Was feasible, both in terms of the construction methods of the day and in terms of any practical constraints imposed by the gun's manner of use. The practical effect of long barrels for modern guns is that the projectile spends more time in the barrel before it exits, and hence more time is available for expanding gas from the controlled burning of the propellant charge to smoothly accelerate the projectile, bringing about

7917-617: Was filled with molten iron and was intended to break up on impact with an enemy ship, splashing molten iron on the target. It was used by the Royal Navy between 1860 and 1869, replacing heated shot as an anti-ship, incendiary projectile. Two patterns of incendiary shell were used by the British in World War ;I, one designed for use against Zeppelins. Similar to incendiary shells were star shells, designed for illumination rather than arson. Sometimes called lightballs they were in use from

8008-430: Was invented by Valturio in 1460. The carcass shell was first used by the French under Louis XIV in 1672. Initially in the shape of an oblong in an iron frame (with poor ballistic properties) it evolved into a spherical shell. Their use continued well into the 19th century. A modern version of the incendiary shell was developed in 1857 by the British and was known as Martin's shell after its inventor. The shell

8099-459: Was not always the case. Some were named after the weights of obsolete projectile types of the same caliber, or even obsolete types that were considered to have been functionally equivalent. Also, projectiles fired from the same gun, but of non-standard weight, took their name from the gun. Thus, conversion from "pounds" to an actual barrel diameter requires consulting a historical reference. A mixture of designations were in use for land artillery from

8190-446: Was still in wide use in World War II . The percentage of shell weight taken up by its explosive fill increased steadily throughout the 20th Century. Less than 10% was usual in the first few decades; by World War II , leading designs were around 15%. However, British researchers in that war identified 25% as being the optimal design for anti-personnel purposes, based on the recognition that far smaller fragments than hitherto would give

8281-644: Was used by the United States beginning in 1906. Germany began filling artillery shells with TNT in 1902. Toluene was less readily available than phenol, and TNT is less powerful than picric acid, but the improved safety of munitions manufacturing and storage caused the replacement of picric acid by TNT for most military purposes between the World Wars. However, pure TNT was expensive to produce and most nations made some use of mixtures using cruder TNT and ammonium nitrate, some with other compounds included. These fills included Ammonal, Schneiderite and Amatol . The latter

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