A Brief Introduction To Ammunition_48715

What do we mean by the term 揂mmunition? The Encyclopaedia Britannica defines it as: The projectiles and propelling charges used in small arms, artillery, and other guns. Microsoft Encarta defines it as: Ammunition includes high-explosive shells, anti-tank shells, smoke and signal shells, shells containing chemical agents, and shells with nuclear warheards. Shells filled with propaganda leaflets and shells that deliver vital medical supplies to isolated troops are also fired by cannon. All of the above shows a remarkable ignorance of what ammunition really is, which is: All of those items that are filled or intended to be filled with explosives. All those items that are thrown, dropped, placed or projected with the intention of doing damage to a thing, place or person These things are in any one of the following groups: Small arms ammunition Grenades Mines, naval Mines, land Torpedoes Rockets Demolition explosives Pyrotechnics Bombs Artillery Propelling charges Fuzes Cartridge cases And these groupings are very broad indeed encompassing several sub branches of the ammunition field. Initially the ammunition field consisted of what isn抰 really considered to be ammunition at all, for example: Rocks and Stones Ammunition you ask? Yes! What did the ancient people throw at one another if not rocks and stones? What was loaded into the sling that was used to kill Goliath? A stone! What was dropped through the machicolations in castle walls? Stones and boiling oil and other horrible things that抯 what. What was hurled in the baskets of trebuchets? Big stones that抯 what. And someone had to select the stones and give them a rough dressing to a round shape, or go around the river bank and select the right size stone for throwing or dropping. I contend that all these people in their own way were ammunition workers. Arrows and Spears Ammunition you ask? Yes! What did the ancient people fire at one another if not arrows? What did the ancients throw at one another if not spears? I contend that the ancient village blacksmith making arrows or spear heads was just as much an ammunition worker as Sadie the munitions worker at Woolwich in 1915. The ancient Fletcher putting flights on arrows was surely an ammunition worker. Did not the Romans develop the one-shot spear, the pilum? It bent on impact and was useless for throwing back. Was this not an ammunition item with a great deal of thought put into its manufacture? Quoits Ammunition you ask? Yes! Did not the Sikhs use steel quoits with sharpened edges to hurl at the enemy? Each soldier carried half a dozen of these things and surely these must be considered ammunition! Greek Fire Ammunition you ask? Yes! These mixtures were designed to drench the enemy in fire, burn his ships, set fire to his buildings and generally discomfit his troops. Isn抰 this just an early version of incendiary ammunition? I believe so! I think that where the definitions above err is in connecting the term ammunition and explosives together and making the assumption that ammunition is automatically explosive in some way. For example would you describe an armour piercing shot consisting of a specially shaped piece of hardened steel as explosive? No, yet it is a piece of ammunition used extensively during WWII! Would you describe a long rod, fin stabilised armour piercing shot as explosive? No, yet it was destroying tanks at 2000metres in Iraq not so long ago. During WWI the airmen used to drop small arrow shaped pieces of steel from great heights onto the troops below. They used the effects of gravity for their propulsion system. None of them were explosive but they certainly caused casualties. Surely these must be considered as ammunition! Just where the connection between ammunition and explosives occurred is not a date but a gradual blending of two ideas. It all commences somewhere in China where gunpowder was invented at a time and place unknown. The substance and its formula passed to Europe probably through the medium of the Spanish or Portuguese explorers. It was certainly known in Europe by 1326 as there are extant documents detailing the method of manufacture and some of its properties. It is from this point that the story of ammunition becomes welded to explosives where it has remained ever since. For the first 500 years gunpowder was the explosive and the propellant, it was the medium of fuzes and pyrotechnics. It provided vast amounts of entertainment via fireworks displays and, in later more enlightened times it provided huge nights of entertainment in Guy Fawkes memorials. In the 19th century major movements began to take place in chemistry, metallurgy, optics and allied subjects. There began to take place huge movements in knowledge as people began to gain education and read more. Books proliferated, each book adding a small increment to the growing body of general knowledge. All this added up to a great advance in the sciences of the time. This meant that suddenly new substances were being invented; old substances were being applied to new uses. And swiftly there appeared new explosives to be used along side the old and venerable gunpowder. But these new explosive were different not only in type but in kind. These new explosives didn抰 just explode they detonated. The difference between detonation and explosion is chalk and cheese. They are vastly different phenomena. Now all of a sudden projectiles were being filled with these new explosives and were demonstrating wonderful new power and violence. So much so that within twenty years of the appearance of the new explosives, gunpowder was swept from the position of pre-eminence that it had held for 500 years. Mind you gunpowder is still with us and will probably never be completely dispensed with as it has some applications in which it is unmatched by any other substance. The new explosives forced the explosives engineers to create a new branch of explosives, high explosives. The old gunpowder was relegated to the new position of, low explosive. Amongst all of this new development was the creation of newer and better propellants. This was because the chemical engineers were learning more and more every day. Suddenly propellants could hurl projectiles great distances with an increase in accuracy hitherto undreamt of a scant decade before. The new metallurgy of the day made guns of vastly increased strength so that the new propellants could be utilised to the fullest. The 19th century began with gunners shooting at one another over open sights at ranges of one or two kilometres. It ended with them shooting at one another at twenty or thirty kilometres where they couldn抰 see each other. Later, in the next century the Germans developed guns that put projectiles into the edge of space and had to take into account the earths rotation while the projectile was in flight. Serendipity played a part in the world of ammunition just as it does everywhere else. An engineer noticed that the name carved into a block of explosive was imprinted into the plate on which he was doing some experiments. This led to the development of hollow charge ammunition which gave unbelievable penetration of armour plate, making the tank a less formidable adversary. Explosives now being more chemically stable could be stored for longer periods and in the case of things like mines they could be laid somewhere and confidently expect that some time in the future they would work as intended. The greater stability meant that great stocks could be put aside for future use thus providing an emergency reserve in time of peril. All of these new explosives and ideas were applied to the ammunition field and a whole range of new items appeared and are still appearing today. This is what most people mean when they say ammunition: the cartridges that are used in rifles, pistols, sub-machine guns and machine guns. They are one of the following: Ball: This name is a hangover from the days when the early weapons used a round ball as the projectile. With the advent of the pointed projectile the name stuck to them too even though they aren抰 a ball shape. Today they consist of a metal jacket with a lead core pressed inside. Sometimes the core will be of other materials such as mild steel; this is purely a cost cutting measure. Tracer: These are projectiles with a pyrotechnic element put in place of the core. During flight the element burns giving off either flame or smoke. The emission of these gives the gunner the ability to see where the projectiles are going and he or she can adjust their aim to hit the target. At close range they sometimes have an incendiary effect, but this isn抰 intended. Armour Piercing: These are designed with a hardened steel or tungsten core. They are intended to defeat relatively thin armour plate such as the armoured seats of pilots or the light armour of armoured personnel carriers. They are very limited in what they will penetrate. There are version called semi-armour piercing, these are cartridges that have failed penetration tests but have been put into service with a reduced capability. Incendiary: These are designed to start fires in any flammable material in the target such as fuel tanks, magnesium components in aircraft etc. They are found in several basic types: Ones filled with White Phosphorous Ones filled with a pyrotechnic mixture and some sort of ignition system. Ones filled with either of the above that are ignited on firing and burn on the way to the target. Blank: These are designed to simulate the noise of a ball cartridge. They are used to train troops in fire and movement drills.They are found in several types: All plastic bodies All Brass bodies Hybrids with a mixture of other materials including paper and wood bullets. Drill or Dummy: These are inert cartridges used to train troops in the safe handling of weapons. They are the same shape as a standard cartridge but they are marked as clearly as possible to be a drill type. Grenade Launcher: These are designed to propel grenades from the end of service rifles. These are also very clearly marked to show their intended purpose. Grenades The hand grenade has a long and distinguished career. It originated in the siege warfare of yesteryear but when more mobile warfare came into being they dropped out of favour. Their resurgence came about in WWI when the horrible trench warfare demanded a means of getting at troops in protected bunkers and trenches. The grenade was the answer and since that time they have been part of every soldier抯 equipment. The come in a variety of styles the main types being: Anti-Personal: These are of two types the defensive and the offensive The defensive is designed to be thrown from under cover because its fragmentation pattern is lethal over a fairly large area. This area is wider than the thrower can throw it. This means he or she is in the lethal area if using them in the offensive sense. The offensive is designed to be thrown by the user when he or she is in the open. The lethal range is very small, in some cases being only 4 or 5 metres. In most cases these grenades use only blast as their main effect. Some grenades are designed to be both, being provided with only a blast effect for offensive work and a fragmentation sleeve for use when defending. The thrower puts on the fragmentation sleeve as and when the circumstances dictate. All anti-personnel grenades are about ?a kilo in weight and almost all have a high explosive filling with a time fuze to control its detonation. Most of them today have a smooth body with the fragmentation embedded in a matrix inside. Anti-Tank: These are designed to attack tanks and are almost all provided with a hollow charge. Some are provided with a very large high explosive charge to attain the same result. It is a bit difficult to throw these heavy grenades any great distance. Many of these types are launched from service rifles, meaning that the operator can tackle tanks at a reasonably safe distance. Some of the early versions were designed to be attached to the tank by means of a sticky substance, a very dangerous exercise. Smoke: These are designed for several purposes and these are signalling and screening. Signalling grenades are filled with a compound that produces a coloured smoke when burned. The colour can be varied. In emergencies these types can also be used a screening smoke although they are not as efficient in this respect. Screening smoke grenades are designed to produce a large volume of smoke for the purposes of screening your movements from observation by the enemy. They can also be used as a signalling medium. Some of these screening smoke grenades are filled with White Phosphorus that has a very strong incendiary characteristic although not intended as such. Incendiary: These grenades are designed to destroy targets by fire and they are usually filled with Thermite or some other incendiary material. They burn with an exceedingly hot flame sufficient to melt the best of steels. They can under the right circumstances be used in the anti-personnel role although not intended as such. Practice: These grenades are designed to replicate the functioning of the standard anti-personnel grenades with the exception that they have a very small gunpowder charge that provides no lethal fragmentation. They are designed for use over and over again, each time being recharged and re-fuzed. They are very clearly marked as to being a practice item. Dummy: These are designed to replicate the anti-personnel grenade in all respects except that they have no explosive components and are used purely to train troops in the safe handling and throwing of grenades. Artillery Ammunition Artillery has come a long way from the days of the round cannon ball, a heap of gunpowder and a crude cannon being fired by a hot stick. Today we have a range of projectiles with specific targets in mind and these are: High Explosives: This is the standard projectile fired by most artillery pieces. It is filled with high explosive and is designed to attack personnel, materiel, bunkers and trench systems. It achieves its aims via two effects and these are: Fragmentation Blast. Fragmentation is achieved by designing the body so that it splinters into the optimum size range. Blast accompanies the bursting of the body into fragments. Armour Piercing: Armour piercing shells come in two types and these are: Kinetic Energy Projectiles: Armour piercing (AP) Armour piercing capped (APC) Armour piercing capped ballistic capped (APCBC) Armour piercing discarding sabot (APDS) Armour piercing fin stabilised discarding sabot (APFSDS) These are designed to attack armour plate whether it is on a tank or a ship using only the energy gained from high velocity. They consist of a very hard core protected at the point by what are called penetrative caps and another cap provided to give the projectile a nice ballistic shape. APDS gains great velocity by providing a carrier for the hard core that falls away at the muzzle leaving just the core to fly to the target. APFSDS are the latest versions and are known as magic bullets. They use tungsten carbide as the metal or sometimes depleted Uranium. They possess very high velocity and, being very thin the penetration is very deep. In the case of depleted Uranium there is an added benefit in that the depleted Uranium is Pyrophoric which means it gives off great showers of sparks and flame on impact. Chemical Energy Projectiles: High explosive Anti-tank (HEAT) - these use the clever stratagem of shaping the explosive charge to concentrate the explosive energy in one spot. This gives an enormous increase in penetration. High explosive squash Head (HESH or HEP) - These utilize the phenomena of shock wave reflection in armour plate to cause large pieces of the inner face to break off and fly round inside the vehicle. They can be easily defeated by providing plates of metal hanging on the outside of the tank which is destroyed by the HESH shell but in doing so they protect the tank from the attack. It should be noted that any one of these projectile provides a very large danger area around the outside of the target because the blast is quite large. The fragmentation is minimal as they aren抰 designed to provide fragmentation. Carrier Projectiles: There are a variety of these such as: Smoke Shell Star shell Illumination Propaganda Smoke shell: These carry canisters of smoke composition that are ignited and expelled by a time fuze at a predetermined time. They are designed to produce coloured smoke at the target area for marking purposes, to provide screening effects for troop movements etc. Star shell: These carry pyrotechnic stars that are ignited and ejected at some time in the flight of the shell so that the stars fall to earth as a signal. Illumination: These carry a reasonably large pyrotechnic device attached to a parachute. Using a time fuze the illumination candle is ignited and expelled at a predetermined time and the parachute slowly lowers the candle to the earth. During its descent to the ground it provides illumination over a large area for observation purposes. Propaganda: These carry propaganda leaflets in tightly packed bundles. Using a time fuze they expel the leaflets over the enemy lines. It should be noted that all of the above projectiles carry an added hazard in that the empty body after ejecting its contents represents a lethal piece of steel. They fall to earth from a great height with lots of remaining velocity and as a result can and do cause casualties. Mortar Projectiles: These are the only remaining muzzle loading artillery in use today. They are designed to attack troops in deep trenches and fortifications and behind natural obstacles such as hills. They fire a projectile at a large angle so that it comes to earth in a plunging manner. They fire the following types: High Explosives: These are designed and operate in the same manner as a normal artillery shell. Smoke Projectiles: Once again designed and operate as for a normal artillery shell Illumination: Exactly the same as the artillery version. Mines These are found in two very distinct families: Naval mines and Land mines. Naval Mines Naval mines are those mines laid in water and are all designed to attack ships. All of them use large high explosive charges to achieve their effect. They come in a variety of types: Drifting Moored Antennae mine Land Mines Land mines are found in two distinct families: Anti-personnel and Anti-tank. Anti-personnel are designed to attack the soldier and are usually small, easily concealed and intended to wound more than kill. They come in several types and these are: Simple anti-personnel: These are designed to function when stepped on and simply explode causing damage to the victim. Bounding type: These are designed to spring out of the ground prior to exploding. They are provided with extra fragmentation so that not only the person tripping the mine is injured but some of the people in the vicinity are also injured by the large spread of fragments. Anti-tank: Anti-tank mines are designed to attack tanks and other vehicles. They are large, harder to conceal and usually have a large explosive charge. Their anti-personnel effect is quite large in addition to their main role. Most anti-tank mines rely on a large high explosive charge to attack the underbelly of a tank where the armour is the thinnest. The large charge can also be expected to damage the track system of the tank thus rendering it immobile. Anti-tank minefields are normally sown with anti-personnel mines to provide a nuisance value to the minefield. Anti-tank mines come in several varieties and these are; Off route mine: These are designed to be placed in such a manner at to attack the side of a tank when the tank runs over a firing mechanism situated on the expected path of the tank. Hollow charge mines: These utilise the penetrative qualities of the hollow charge to attack the thin belly of the tank. They are quite often provided with a rod to operate the fuze mechanism thus ensuring the belly is attacked. Should the track run over the mine then it will still operate and destroy the track system. Torpedoes Torpedoes are designed to attack ships by either striking the ship directly or exploding beneath the ship. Those that strike the ship utilise the effect of a large quantity of explosives detonating against the steel plates of the ship and letting in the water. Those that explode beneath the ship utilise the effect of suddenly taking away the supporting water from beneath the ship, this action causes the weight of the ship to break its own keel. They come in several varieties today and these are: Acoustic Acoustic torpedoes come in two types active and passive: Active generates a sound that it can read when it bounces back from a target Passive has a receiver that picks up the sounds generated by the target itself. The signals in both cases is amplified and used to close an electric circuit. Wire guided Wire guided torpedoes are attached to the launching platform by a wire system thatenables the torpedo to be guided to its target. In modern terminology the type of torpedo that does its own searching is called a 揊ire and forget? Torpedoes are also characterised by the method of launching; Air launched Submarine launched Ship launched Demolition Explosives: These items are the application of explosives to perform various demolition tasks. They come in a vast number of shapes, sizes and explosives. Some of the types to be encountered are: Explosive charges Timing fuzes Instantaneous fuzes Detonating cords Detonators Matches for igniting fuzes Explosive Charges: These are designed to be placed in such a way as to destroy some object. They vary from charges as small as 35 grammes to some weighing many tonnes. They come in blocks, cylinders, flat sheets, curved blocks, long strips and the favourite of movie directors, Plastic malleable material. Some specialist charges are made up into lead hollow charges for use in cutting the locks out of doors or clearing a window out of the way for quick entry. Many of them are contained in light tinned plate canisters; some are placed in cardboard boxes. Lots of them are waterproofed so that they may be put in place for demolition at a later date. Timing Fuzes: These are designed for use with detonators and are used to allow the demolition expert to get away from the area when the charge explodes. They consist of a core of compressed gunpowder encased in a waterproof outer covering. The gunpowder core is compressed to a known density that gives a constant burning rate, which permits accurate timing of the moment of explosion. Instantaneous Fuzes: These are made to the same style as timing fuzes but the rate of burning has been adjusted so that their action is very rapid. The speed is usually around 30 metres a second. They are typically used in booby traps so that the victim has no time to react to his or her error. Detonation Chords: These are long thin cords with a core of high explosive with a very high velocity of detonation, usually of the order of 9 kilometres a second. That抯 right 9000 metres a second. They are used to connect multiple charges together so that virtually instantaneous detonation of all the charges is achieved. Short pieces can be used in booby traps to provide even less time for the charge to explode. Detonators: These are very small containers filled with a very sensitive high explosive. They are designed to accept the flash from timing fuze and converting that flash into a detonation for exploding a demolition charge. They come in two types: Non-Electric: These are a simple tube, usually of aluminium with a small quantity of explosives pressed in the bottom of the tube. The top layer is a sensitive primary explosive such as fulminate of mercury the bottom layer is a less sensitive explosive such as CE. The flash from the timing fuze is picked up by the top layer and transferred into a detonation. Electric: These operate in the same manner except that the flash is provided by a match head inside the detonator tube. The initiation of the match head is caused by an electric current. Thereafter all the events are the same. The electric detonator provides the ability to build in a delay element so that explosives used in mining operations can be exploded in tightly controlled sequences. Matches: These are special matches that are designed to burn for a longer time than is found in your normal household match. They are recognisable by their very large heads. There are versions that are called 揗atches fuzee?and these are a very large match indeed. They are designed to burn for quite a long time, in some cases for 5 minutes or so. They permit the demolition person to ignite timing fuzes at widely spaced intervals without the necessity of lighting a match at each site. Bombs All bombs are measured not only by their role but by weight. For example a General purpose bomb can be 20kg, 100kg, and 250kg all the way up to 2000kg. They also can be expressed in terms of capacity thus a high explosive bomb can be classed as a high capacity by virtue of the fact that the case has been reduced to the minimum weight possible and the filling as a result is a large percentage of the overall weight. For example during WWII the British discovered that a bomb doesn抰 need a big strong case, nor a streamline one so they developed the 1814kg 揅ookie?then some bright individual decided to hood two of them together thus creating the 3628kg 揝uper cookie? Needless to say someone finally said 揕ets hook three of them together to make a 揝uper, super cookie?this was done and they were called 揃lockbusters? High Explosive Bombs These come in a variety of types viz; General purpose: These are designed with a view to providing adequate blast with some fragmentation effect. They are used for general purpose bombing of troops and buildings, for attacking oil refineries, transport systems etc. They consist of a high explosive filling inside a steel case that is streamlined and provided with a set of stabilising fins. They can be found in weights up to 3628kg. High Capacity: These are designed to possess a larger blast effect at the expense of fragmentation. They are used to attack factories, canals, refineries and any other target that is susceptible to blast damage. They are usually not streamlined. Deep penetration: These are designed to penetrate as far as possible into the earth before exploding. They are therefore very heavy, very streamlined and have a good quality steel body. They are large so that the filling has a good charge weight ratio. The great historical versions of these are the British medium capacity 5443kg 揟allboy?and the 10,886kg 揋rand Slam?used during WWII. Historically of course the idea of a deep penetration bomb surfaced again in Iraq when the Americans discovered that the Iraqi抯 were hiding in deep bunkers. The Americans took some old naval gun barrels and made bombs out of them with a long delay fuze and good streamlining they were able to reach the hiding people. Incendiary: These are filled with some very flammable material and a light case fitted with a bursting charge designed to rupture the case and scatter the filling thus setting fire to the target. During WWII it was discovered that if you dropped large explosive bombs first and then incendiaries later the explosive bombs would de-roof buildings and let in the incendiaries, which operated more efficiently. Flare: These are designed to produce a large light to illuminate an area so that aerial photography may be carried out. These are sometimes called 揚hotoflash? Target Indicators: These are designed to be dropped on the ground in the vicinity of your target to indicate to the bomber force just where to drop their bombs. They consist of a large quantity of flare material with a long burning time and a distinct colour. Nuclear bombs: These come in two basic types Nuclear and Thermonuclear the difference being that nuclear uses conventional explosives to bring together two pieces of fissionable material of carefully selected weight. Neither of the two is near critical mass, but bringing them together exceeds the critical mass and they begin a chain reaction resulting in nuclear fission. Thermonuclear on the other hand uses a nuclear bomb to cause a mass of hydrogen to be squeezed together thus creating a miniature fusion reactor that proceeds to a fusion reaction. Propelling Charges These are those explosives that are used to drive projectiles from weapons and as such are low explosives. They come in many variations but the major groups are: Single Base - made from nitrocellulose only Double Base - made from Nitrocellulose and Nitroglycerine Triple Base - Nitrocellulose, Nitroglycerine and Guanidine The groupings are based on the basic ingredients used to make the propellant. In addition propellants are graded in accordance with their shape thus: Cordite is made in long spaghetti shaped pieces and much beloved of crime writers as each weapon that is fired leaves the odour of cordite in the air. The problem is that cordite hasn抰 been made for years. Flake is made in little squares. Tubular is made in hollow tubes Multi-tubular is made in cord like pieces with several perforations through it. Some rocket propellants are made in odd shapes like stars or cogged wheels. In addition propellants are graded in accordance with their place of manufacture or the added ingredients thus;Waltham Abbey ModifiedCordite MD (Cordite with mineral detergent added) Fuzes A fuze is a lock that requires very special forces to open. These forces are; A very violent acceleration from a standing start A very high rate of spin A huge push on the base A gradual retardation in flight A massive retardation on impact or graze with the ground. A close approach to a target. Not all of these forces are required for each individual fuze, some use all of them some use only one or two. Fuzes come in various types and these are: Artillery Mortar Bomb Grenade Mine They are characterised by position and by function for example: Point initiated, base detonated Point detonated, super quick. They are characterised by type. Direct impact: These fuzes are designed to function on impact with the target. The problem soon discovered was that they won’t work if they land on their edge. Direct impact and graze: These are designed to overcome the problem mentioned above. They have some mechanism that senses the side impact and operates the fuze as though it had struck the target squarely. Combustion time: These use gunpowder to burn in a very controlled manner to time an amount of flight time. Time and percussion: These combine the elements of combustion timing with an impact element. They are designed to ensure that if the timing element fails then the impact will work and vice-versa. Mechanical time: These are made with a clockwork mechanism that carries out the timing functions of the time combustion fuze. Proximity: These fuzes are sometimes called 揤ariable time fuzes? They are in fact a miniature radio transmitter and receiver that measures the distance from a target and, at the optimum distance it detonates the shell. Adiabatic: These fuzes operate on the principle of the diesel stroke heating a column of air so that it ignites a detonator which burns to detonation. The great problem is that they don抰 function well on soft ground or water, as the diesel stroke doesn抰 get a chance to get into stride. Fuzes characterised by application: Mortar fuzes: These are different in that the mortar isn抰 rifled so the fuze doesn抰 have the violent spin used by artillery fuzes. They use a clever device called a 揃ore riding pin?this is a spring loaded pin that holds safety devices in place while the mortar round is in the bore, but they are released when the pin flies out when it leaves the bore. Mortar fuzes are generally simpler than artillery fuzes as they are limited in the number of dynamic forces available. Aerial bomb fuzes: These fuzes don抰 have any of the violent forces used in artillery fuzes so they use wire safety devices to prevent the fuzes from arming until the moment of dropping. To carry out the arming process once the bomb leaves the aircraft they use little propellers to wind safety devices out of alignment or move other components into alignment with explosives trains. Aerial bombs are characterised by position: Nose fuzed Tail fuzed Grenade fuzes: These are usually of the time combustion type. They don抰 use any violent forces but use simple mechanical devices to retain a striker system until the moment the thrower releases the grenade. Some grenades use the simple burning fuze system whereby the fuze is ignited by a percussion element. Particularly the Japanese type 91 where the thrower struck the fuze against any hard surface which started the fuze burning. They were originally of the impact type but these proved very dangerous in trenches as the thrower could accidentally strike the grenade on the rear wall of a trench. The advent of the time combustion fuze made throwing grenades a much safer proposition. Mine fuzes: These come in two varieties applied to their respective mines, land and naval. Land mine fuzes: These come in two varieties Anti-tank and Anti-personnel. Anti-tank fuzes: These are designed to be operated by a very heavy vehicle of truck or tank dimensions. They usually rely on very strong springs and shear wires to provide the safety after laying. Typically they require pressures in the region of 150 to 200 kilogrammes to make the fuze work. Anti-personnel: Anti-personnel mine fuze are almost always quite small and require only low pressures to operate. Typically around 10 to 30 kilogrammes. Some of these fuzes are designed to cause the mine to be ejected from the ground before detonation. Naval mine fuzes: These come in two basic types; Contact - these operate on the simple procedure of the ship striking a device filled with acid and other chemicals that are mixed by the impact thus creating an electrical system that explodes a detonator. These devices are called 揌erz horns? Influence - These devices are found in various types and some of these are: Magnetic - magnetic influence fuzes operate by sensing the magnetic field of the ship and causing a needle to move and make contact with an electrical circuit. Pressure - pressure type fuzes use the pressure wave in water generated by a ship under way. The pressure wave is used to move a sensitive mechanical device thus closing and electrical switch. Accoustic - acoustic mine fuzes operate by picking up the sound of a ships engines, propellers and general hull noises, amplifying the signal and using it to close an electrical circuit. Cartidges, cases and bags These are the containers for holding the propellant charges that drive the projectiles in artillery, mortar, anti-submarine and engine starter ammunition. They come in two groups and these are; Cartridge cases Charge bags Cartridge cases are usually made from brass, although they may be encountered in steel, plastic or a combination of all three. They come in a huge range of shapes and sizes and they are usually characterised by the calibre of the projectile they are used with and the length of the case. In addition the type of rim is specified also. For example a 37mm case in described as 37x223R, which indicates that it is 37mm in calibre, the case length is 223 mm and it is rimmed. Some of these cartridge cases are immense requiring machinery to handle. These types are usually restricted to use on board ships where weight factors are not an insurmountable problem. Charge bags are made usually from cloth of some type. They are fitted with an igniter on the base to ensure full ignition of the charge. The materials are selected with several conflicting requirements in mind. They must be strong, cheap and leave no burning residue in the barrel. As can be imagined there are very few materials that meet these stringent requirements. Mostly serge and silk are used. Much use is being made of plastic especially in mortar propellant increments. It is to be noted that the subject of ammunition is immense and is still in the process of being created. It is too large to explain in any meaningful way in a brief introduction. But the above is a rough guide to ammunition. Much has been left out for space reasons. Written by: Ammunition Pages - Ammunitions of the World for collectors, historians and general enthusiasts alike. Download the original article and more like it at http://www.ammunitionpages.com/