A shell is a projectile, which, as opposed to a bullet, is not solid but contains an explosive or other filling. A projectile is any object sent through the air by the application of some force. ... This article is about the projectile, for other uses see bullet (disambiguation). ...

These objects of weaponry are generally large rounds fired by artillery, armored fighting vehicles (including tanks), and warships, such as battleships. The bayonet, still used in war as both knife and spearpoint. ... Historically, artillery refers to any engine used for the discharge of projectiles during war. ... An armoured fighting vehicle (AFV) is a military vehicle, equipped with protection against hostile attacks and often mounted weapons. ... USS Port Royal (CG-73), a Ticonderoga class cruiser. ... This article is about a battleship as a type of warship. ...

Most shells are aerodynamic and hence, tend to have similar shapes to bullets—that is, a cylinder topped by an ogive shaped nose, possibly with a tapering base—but some specialised types are quite different. The word cylinder has several meanings. ... In ballistics or aerodynamics, an ogive is a pointed, curved surface used to form the approximately streamlined nose of a bullet, shell, missile or aircraft. ...

History

Explosive shells do not appear to have been in general use before the middle of the 16th century. About that time hollow balls of stone or cast iron were fired from mortars. The balls were nearly filled with gunpowder and the remaining space with a slow-burning composition. This method was fairly ineffective as the charge was not always ignited by the flash from the discharge of the gun, and moreover the amount of composition to burn a stipulated time could not easily be gauged. (15th century - 16th century - 17th century - more centuries) As a means of recording the passage of time, the 16th century was that century which lasted from 1501 to 1600. ... Soldier Firing the M224 60mm Mortar. ... Gunpowder is a substance which burns very rapidly and is used as a propellant in firearms. ...

The shell was, therefore, fitted with a hollow forged iron or copper plug, filled with slow-burning powder. It was impossible to ignite with certainty this primitive fuze simply by firing the gun; the fuze was consequently first ignited and the gun fired immediately afterwards. This entailed the use of a mortar or a very short piece, so that the fuze could be easily reached from the muzzle without unduly endangering the gunner. Cast-iron spherical common shell were in use up to 1871. For guns they were latterly fitted with a wooden disc called a sabot, attached by a copper rivet, intended to keep the fuze central when loading. They were also supposed to reduce the rebounding tendency of the shell as it travelled along the bore on discharge. Mortar shell were not fitted with sabots. 1871 was a common year starting on Sunday (see link for calendar). ... A sabot (French: shoe) is a device used in a firearm or cannon to fire a projectile or bullet that is smaller than the bore diameter. ...

Cast iron held its own as the most convenient material for projectiles up to the end of the 19th century, steel supplanting it, first for projectiles intended for piercing armour, and afterwards for common shell for high-velocity guns where the shock of discharge has been found too severe for cast iron. Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ...

During the First World War, shrapnel shells inflicted terrible casualties on infantry - accounting for nearly 70% of all the casualties of the war. Shells filled with poison gas were used from 1917 onwards. Frequent problems with shells led to many military disasters when shells failed to explode, most notably during the 1916 Battle of the Somme. Ypres, 1917, in the vicinity of the Battle of Passchendaele. ... Shrapnel, in the strict sense, is shot deliberately included in a landmine or shell intended to be scattered by the explosion. ... Gas (actually as, part of the Gnu Binutils package) is the default Gcc Back-end. ... 1917 was a common year starting on Monday (see link for calendar). ... 1916 is a leap year starting on Saturday (link will take you to calendar) Events January-February January 1 -The first successful blood transfusion using blood that had been stored and cooled. ... See Battle of the Somme (disambiguation) for other battles and meanings Battle of the Somme Conflict First World War Date 1 July 1916 – 18 November 1916 Place Somme, Picardy, France Result Stalemate The 1916 Battle of the Somme was one of the largest battles of the First World War, with...

Calibre

The calibre of a shell is its diameter. Depending on the historical period and national preferences, this may be specified in millimetres, centimetres, or inches. Care should be taken as the length of gun barrels is frequently quoted in terms of calibre. The word caliber (American English) or calibre (British English) comes from the Italian calibro, itself from the Arabic quâlib, meaning mould. ... For the geometric term, see diameter. ... A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ... cm redirects here, alternate uses: cm (disambiguation) A centimetre (symbol cm; American spelling: centimeter) is an SI unit of length. ... Mid-19th century tool for converting between different standards of the inch An inch is an Imperial unit of length. ...

Due to problems of manufacture, the lower size limit for shells is a calibre around 20 mm, used in aircraft cannon and on armoured vehicles. Smaller explosive projectiles exist, but they are rare. The largest shells ever fired were those from the German super-railway guns, Gustav and Dora, which were 800 mm (31.5") in calibre. Very large shells have been replaced by rockets, guided missile, and bombs, and today the largest shells in use are 203 mm (8 inches). Guns of that size are uncommon; 155 mm (6 inches) is the largest calibre in common use. A railway gun (also called railroad gun, and formerly called a railgun durring World War I and World War II) is a large artillery piece, designed to be placed on rail tracks. ... The Germans, visible near the base, prepare to fire the gun Schwerer Gustav and Dora were the names under which the 80-cm K (E) siege cannon was known. ... You may mean rocket, as in vehicles, missiles or aircrafts which obtain thrust by the reaction to the ejection of a fast moving exhaust from within a rocket engine. ... This article or section should be merged with Missile guidance A guided missile is a military rocket that can be directed in flight to change its flight path. ...

Gun calibres are standardized around a few common sizes, especially in the larger range, mainly due to the uniformity required for efficient military logistics. Shells of 105, 120, and 155 mm diameter are common for NATO forces' artillery and tank guns. Artillery shells of 122 and 152 mm, and tank gun ammunition of 100, 115, or 125 mm calibre remain in use in Eastern Europe and China. Most common calibres have been in use for many years, since it is no small feat to change over ammunition stockpiles. Powerful cannon designed to be mounted in a tank as primary armament. ...

The weight of shells varies greatly. A 150 mm (6") shell weighs about 50 kg, a 203 mm (8") shell weighs either 100 kg or 146 kg (concrete demolition variant). Of the largest calibres, used exclusively on battleships, a 280 mm (11") shell weighs about 300 kg, and a 460 mm (18") shell weighs over one and a half tonnes. The two types of projectiles used with the Nazis' Dora mega-gun measured 5 and 8 tonnes, respectively.

Old-style United Kingdom classification by weight

Historically, shells were often described in pounds in the UK, e.g., as "two-pounder ammunition", or "2-pdr". Usually this refers to the actual weight of a high explosive (HE) shell, but confusingly, this was not always the case. Some were named after the weights of obsolete shell types of the same calibre, or even obsolete shell types that were considered to have been functionally equivalent. Also, non-HE shells fired from the same gun, but of different weight, were assigned the same poundage. Thus, conversion from "pounds" to actual barrel diameter requires consulting a historical reference. Officially the pound is the name for at least three different units of mass: The pound (avoirdupois). ...

Types

There are many different types of shells. The principle ones include:

High explosive (HE)

The most common shell type is high explosive, commonly referred to simply as HE. HE shells have a strong steel case, a bursting charge, and a fuse. When the fuse initiates the shell, the bursting charge shatters the case and scatters hot, sharp fragments of steel at high speed. Most of the damage is caused by being struck by these fragments, rather than directly by the blast. Depending on the type of fuze used the HE shell can be set to burst on the ground, in the air above the ground, or after penetrating a short distance into the ground (either to transmit more ground shock to covered positions, or to reduce the spread of fragments). This article is concerned solely with chemical explosives. ... Steel framework Steel is a metal alloy whose major component is iron, with carbon being the primary alloying material. ... In an explosive device, a fuse is the part of the device that causes it to function. ...

Armour-piercing (AP)

In naval warfare and older anti-tank shells, the shell had to withstand the shock of punching through armour plate. Shells designed for this purpose had a greatly strengthened case with a specially hardened and shaped nose, and a much smaller bursting charge or even no bursting charge for smaller calibres. A further refinement of the design improved penetration by adding a softer metal cap to the penetrating nose giving APC (Armour piercing - capped). The softer cap took away some of the initial shock that would otherwise shatter the round. However the best profile for the cap was not the best for flight. To restore aerodynamics a further hollow cap was added to give APCBC (APC + Ballistic Cap). Explosive AP shells were sometimes distinguished by appending the suffix "-HE" or "/HE". Solid shot AP projectiles were so uncommon, that for unnecessary repetition the suffix "-HE" is usually not used; all projectiles can be assumed to have even small explosive charge. Plain AP shell is now very rarely seen except in naval usage, and is uncommon even there. See also: Armor-piercing shot and shell Anti-tank, or simply AT, refers to any method of combating military armored fighting vehicles, notably tanks. ... A hoplite wearing a helmet, a breastplate and greaves (and nothing else). ... An Armour piercing shell is a type of ammunition designed to penetrate armour. ...

Armour-piercing, discarding sabot (APDS)

APDS was developed by the United Kingdom and put into British service in March 1944 with their 6 pdr and 17 pdr anti-tank guns. For increased penetrating power a high velocity round was required, this in turn required a stronger material (such as tungsten) to withstand the greater shock of impact. Such a shot was too heavy at full bore to be accelerated to a sufficient muzzle velocity, so a lightweight outer carrier, the Sabot, (French shoe) which filled the barrel was fitted around the smaller-diameter shot. This gives the projectile a higher acceleration in the gun's barrel, due to the larger surface area for the gases to impinge upon relative to its weight. Once outside the barrel, the sabot is stripped off by a combination of centripetal force and wind, giving the shot low drag in flight. For a given caliber, this type of ammunition can effectively double the anti-tank performance of a gun over those using "simple" shot. 1944 was a leap year starting on Saturday (link will take you to calendar). ... The 17-pounder (17-pdr) was a 77 mm anti-tank gun developed by the United Kingdom during World War II. It was the best Allied anti-tank gun of the war, able to defeat all German armor and the equal of all their guns up to the massive 88... Anti-tank, or simply AT, refers to any method of combating military armored fighting vehicles, notably tanks. ... A centripetal force is a force pulling an object toward the center of a circular path as the object goes around the circle. ...

A further refinement of the same concept is the armour-piercing, fin stabilised, discarding sabot (APFSDS). In this the projectile is made long and thin to increase its sectional density and thus penetration. However once a projectile is more than about ten times longer than it is wide, spin stabilisation becomes ineffective, so the projectile is instead stabilised by fins attached at its base, and is fired from an unrifled barrel. An APFSDS projectile looks like a big metal arrow. APFSDS projectiles are sometimes made from tungsten, but the most effective types are made from depleted uranium. Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... General Name, Symbol, Number Tungsten, W, 74 Chemical series Transition metals Group, Period, Block 6 (VIB), 6, d Density, Hardness 19250 kg/m3, 7. ... Depleted uranium (DU) is uranium which contains a reduced proportion of the fissile isotope U_235 and (usually) the highly radioactive but rare isotope U_234, compared to natural uranium. ...

APDS and APFSDS rounds are solid "shot" and contain no explosive charge and are not therefore "shells".

Armour-piercing, composite rigid (APCR)

A variation on the APDS theme. A solid high-density metal core surrounded by a full bore shell of lighter material. In effect a discarding sabot that doesn't discard.

High explosive, anti-tank (HEAT)

HEAT shells are a type of shaped charge used to defeat armoured vehicles. They are extremely efficient at defeating plain steel armour but are becoming less useful with the growing prevalence of composite and reactive armour. The power of the shell is independant of the velocity of the shell and is as effective at 1000 metres as at 100 metres. A HEAT charge is most effective when detonated at a certain, optimal, distance in front of the target and HEAT shells are usually distinguished by a long, thin nose probe sticking out in front of the rest of the shell, e.g., PIAT bomb. High explosive anti-tank, more commonly known as HEAT, rounds are made of an explosive shaped charge that uses the Munroe effect to create a very high velocity jet of metal in a state of superplasticity that can punch through solid armor. ... A shaped charge is an explosive charge shaped to focus the released energy. ... This article or section should include material from Explosive reactive armour Reactive armor or explosive reactive armour (ERA), is a type of armour used primarily on tanks to lessen the damage from explosions caused from missile warheads, exploding shells, grenades, or dropped bombs. ... PIAT in use by Canadian troops The PIAT, for Projector, Infantry, Anti Tank, was one of the earlier anti-tank weapons based on a HEAT shell. ...

High explosive, squash head (HESH) or high explosive, plastic (HEP)

A HESH shell is another anti-tank shell also developed by the United Kingdom. It is has a very thin case, and an unusually large charge of a plastic explosive. It is designed to flatten against the face of the armour, and detonate at the time that transfers the maximum shock into the armour plate. When the compressive shock reflects off the air/metal interface inside the tank, it is transformed into a tension wave which spalls a "scab" of metal off the inside of the plate and throws it into the tank. Thus a HESH shell can defeat a tank even without penetrating the armour. High explosive squash head, also known as HESH or HEP (in US usage, for high-explosive, plastic), rounds are a type of anti-tank explosive. ... Plastic explosive (or plastique) is a specialised form of explosive material. ... Spall are flakes of a material that are broken off a larger solid body. ...

HESH is completely defeated by spaced armour (provided that the plates are individually able to withstand the explosion), but remains popular in some armed forces because vehicles without spaced armour are still common, and it is also the most efficient shell at demolishing brick and concrete.

Cluster shells

Like cluster bombs, an artillery shell may be used to scatter smaller submunitions, including anti-personnel grenades, anti-tank top-attack munitions, and landmines. These are generally far more lethal against both armor and infantry than simple high explosive shells, since the multiple munitions create a larger kill zone and increase the chance of achieving the direct hit necessary to kill armor. Most modern armies make significant use of cluster munitions in their artillery batteries. Cluster bomb exploding A cluster bomb is an air-dropped bomb that ejects multiple small submunitions (bomblets). ... The word grenade can mean:- The well-known hand grenade commonly used by soldiers. ... A landmine is a type of mine which is placed onto or into the ground and explodes when triggered by a vehicle or person. ... The US M1A1 Abrams tank is a typical modern main battle tank. ... Infantry in the First World War Infantry (or Infantrymen) are soldiers who fight primarily on foot, using personal weapons. ... Cluster bomb exploding A cluster bomb is an air-dropped bomb that ejects multiple small submunitions (bomblets). ...

Artillery-scattered mines allow for the quick deployment of minefields into the path of the enemy without placing engineering units at risk, though artillery delivery may lead to an irregular and unpredictable minefield with more duds than if mines were individually emplaced. Signatories of the Ottawa Treaty have renounced the use of artillery-scattered mines. A landmine is a type of mine which is placed onto or into the ground and explodes when triggered by a vehicle or person. ... The Ottawa Treaty or the Mine Ban Treaty (formally the Convention on the Prohibition of the Use, Stockpiling, Production and Transfer of Anti-Personnel Mines and on their Destruction bans completely all anti-personnel landmines (AP-mines). ...

Chemical

Chemical shells contain just a small explosive charge to burst the shell, and a larger quantity of a chemical weapon. Signatories of the Chemical Weapons Convention have renounced such shells. Dressing the wounded during a gas attack by Austin O. Spare, 1918. ... The Chemical Weapons Convention is an arms control agreement which outlaws the production, stockpiling and use of chemical weapons. ...

Non-lethal shells

Not all shells are designed to kill or destroy. The following three types are designed to achieve particular non-lethal effects on the battlefield. They are not completely harmless, however; smoke and illumination shells can accidentally start fires, while all three types can cause minor damage (or potentially kill) if property or a person is unlucky enough to be struck by the discarded carrier.

Smoke

The smoke shell is designed to create a smokescreen. The main types are bursting (usually filled with white phosphorus, WP) and base ejection (a shell which scatters smoke grenades). A U.S. Army Humvee laying a smoke screen A smoke-screen is a release of smoke in order to mask the movement or location of military units such as infantry, tanks or ships. ... This article is about the chemical element. ... The word grenade can mean:- The well-known hand grenade commonly used by soldiers. ...

Illumination

Another non-lethal shell type is illumination. An illumination shell has a fuze which ejects the "candle" (a pyrotechnic flare emitting white, coloured, or infrared light) at a calculated altitude, where it slowly drifts down beneath a heat resistant parachute. These are also known as starshell. Pyrotechnics is a field of study often thought synonymous with the manufacture of fireworks, but more accurately has a wider scope that includes items for military and industrial uses. ... Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ... The Apollo 15 capsule landed safely despite a parachute failure. ...

Carrier

The carrier shell is simply a hollow carrier equipped with a fuze which ejects the contents at a calculated time. They are often filled with propaganda leaflets, but can be filled with anything that meets the weight restrictions and is able to withstand the shock of firing. Famously, on Christmas Day 1899 during the siege of Ladysmith, the Boers fired into Ladysmith a carrier shell without fuze, which contained a Christmas pudding, two Union Jacks and the message "compliments of the season". The shell is still kept in the museum at Ladysmith. North Korean propaganda showing a soldier destroying the United States Capitol building. ... 1899 was a common year starting on Sunday (see link for calendar). ... The Siege of Ladysmith was a famous battle in the Boer War, taking place between 2 November 1899 and 28 February 1900. ... Afrikaners are white South Africans of predominantly Calvinist Dutch, German, French Huguenot, Friesian and Walloon descent who speak Afrikaans. ... Christmas pudding is the dessert traditionally served on Christmas day in Britain and Ireland, as well as in some Commonwealth countries. ... Flag Ratio: 1:2 The Union Flag or Union Jack is the flag most commonly associated with the United Kingdom of Great Britain and Northern Ireland and was also used throughout the former British Empire. ...

Unexploded shells

The fuze of a shell has to keep the shell safe from accidental detonation during storage, (possibly rough) handling, and violent launch through the barrel, then reliably detonate it at the correct time. To do this it has a number of safety mechanisms which are successively withdrawn under the influence of the sequence of firing.

Sometimes, one of these safety mechanisms is not disabled during the shell's flight, and the shell fails to detonate on impact. Such a shell is called a blind or UXO. (An older term, "dud", is discouraged because it implies that the shell cannot detonate). Blind shells often litter old battlefields (sometimes burrowed a short distance into the earth), and are extremely hazardous. For example, there is at least one type of blind which can be detonated by a shadow passing across it on a hot day, and most types can potentially be detonated by even a small movement. Unexploded ordnance (or UXOs) are explosive weapons (bombs, shells, grenades, etc. ...

If a blind shell is discovered, it should be avoided, other people warned of its presence, and it should be reported to the local police or armed forces for safe destruction. The armed forces of a state are its military organization. ...