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A hand grenade is any small bomb that can be thrown by hand. A variety of hand grenades exist, the most common being explosive grenades designed to detonate after impact or after a set amount of time.
The word "grenade" derives from the French word for a "small explosive shell". Its first usage in English dates from the 1590s. It is likely derived from Old French pomegranate (influenced by Spanish granada), so called because the many-seeded fruit suggested the powder-filled, fragmenting bomb, or from similarity of shape.
Rudimentary incendiary grenades appeared in the Eastern Roman (Byzantine) Empire, not long after the reign of Leo III (717-741). Byzantine soldiers learned that Greek fire, a Byzantine invention of the previous century, could not only be thrown by flamethrowers at the enemy, but also in stone and ceramic jars. Later, glass containers were employed. The use of Greek fire, or rather variants thereof, spread to Muslim armies in the Near East, from where it reached China by the 10th century.
In China during the Song Dynasty (960–1279AD), weapons known as Zhen Tian Lei (震天雷, "Sky-shaking Thunder") were created when Chinese soldiers packed gunpowder into ceramic or metal containers. In 1044, a military book Wujing Zongyao ("Compilation of Military Classics") described various gunpowder recipes in which one can find, according to Joseph Needham, the prototype of the modern hand grenade. The Chinese also discovered the explosive potential of packing hollowed cannonball shells with gunpowder. The mid-14th-century book, Huolongjing (火龙经, "Fire Dragon Manual"), written by Jiao Yu (焦玉), recorded an earlier Song-era cast iron cannon known as the "flying-cloud thunderclap cannon" (飞云霹雳炮; feiyun pili pao). The manuscript stated that (Needham's modified Wade-Giles spelling):
The shells (pào) are made of cast iron, as large as a bowl and shaped like a ball. Inside they contain half a pound of 'divine fire' (shén huǒ, gunpowder). They are sent flying towards the enemy camp from an eruptor (mu pào); and when they get there a sound like a thunder-clap is heard, and flashes of light appear. If ten of these shells are fired successfully into the enemy camp, the whole place will be set ablaze...
The first cast iron bombshells and grenades did not appear in Europe until 1467. In 1643, it is possible that "Grenados" were thrown amongst the Welsh at Holt Bridge during the English Civil War. The word "grenade" originated during the events surrounding the Glorious Revolution in 1688, where cricket ball-sized iron spheres packed with gunpowder and fitted with slow-burning wicks were first used against the Jacobites in the battles of Killiecrankie and Glen Shiel. These grenades were not very effective (probably because a direct hit would be necessary for the grenade to have effect) and, as a result, saw little use.
However, improvised grenades were increasingly used from the mid-19th century, being especially useful in trench warfare. In a letter to his sister, Colonel Hugh Robert Hibbert described an improvised grenade that was employed by British troops during the Crimean War (1854–1856):
We have a new invention to annoy our friends in their pits. It consists in filling empty soda water bottles full of powder, old twisted nails and any other sharp or cutting thing we can find at the time, sticking a bit of tow in for a fuse then lighting it and throwing it quickly into our neighbours pit where it bursts, to their great annoyance. You may imagine their rage at seeing a soda water bottle come tumbling into a hole full of men with a little fuse burning away as proud as a real shell exploding and burying itself into soft parts of the flesh.
In the American Civil War, both sides used hand grenades equipped with a plunger that detonated the device upon impact. The Union relied on experimental Ketchum Grenades, with a tail to ensure the nose would strike the target and start the fuse. The Confederacy used spherical hand grenades that weighed about six pounds, sometimes with a paper fuse. They also used 'Rains' and 'Adams' grenades, which were similar to the Ketchum in appearance and mechanism. Improvised hand grenades were also used to great effect by the Russian defenders of Port Arthur during the Russo-Japanese War.
The lack of an effective hand grenade and their perceived risk meant that they were regarded as increasingly unnecessary pieces of military equipment. In 1902, the British War Office officially announced that hand grenades were obsolete and had no place in modern warfare. However, within just two years, following the success of improvised grenades in the trench warfare conditions of the Russo-Japanese War, and reports from General Sir Aylmer Haldane, a British observer of the conflict, a reassessment was made and the Board of Ordnance was instructed to develop a practical hand grenade. Various models using a percussion fuse were built, but this type of fuse suffered from various practical problems and were not commissioned in large numbers.
Marten Hale, better known for patenting the Hales rifle grenade, developed a modern hand grenade in 1906, but was unsuccessful in persuading the British Army to adopt the weapon until 1913. Hale's chief competitor was Nils Waltersen Aasen, who invented his hand grenade design in 1906 in Norway, receiving a patent for it in England. He conducted his experiments while serving as a sergeant in the Oscarsborg Fortress. Aasen formed the Aasenske Granatkompani in Denmark, and produced and exported hand grenade in large numbers across Europe in the run up to the First World War. He had particular success in marketing his weapon to the French, and was appointed as Knight of the French Legion in 1916 in honor for the invention.
The Royal Laboratory invented the No 1 Grenade in 1908. It contained explosive material with an iron fragmentation band, with an impact fuse, detonating when the top of the grenade hit the ground. A long cane handle (approximately 16 inches) allowed the user to throw the grenade further than the blast of the explosion.
Improvised weapons were finally replaced when reliable manufactured versions became available. The first modern fragmentation grenade was the Mills bomb, which became available to British front-line troops from 1915. Early in World War I, combatant nations still only had small and relatively unreliable grenades, similar to Hales' and Aasen's design. For example, the Italian Besozzi grenade had a five-second fuse with a match-tip that was ignited by striking on a ring on the soldier's hand. As an interim measure, the troops often improvised their own weapons in the trenches, such as the Jam Tin Grenade.
William Mills, a hand grenade designer from Sunderland, patented, developed and manufactured the "Mills bomb" at the Mills Munition Factory in Birmingham, England in 1915, designating it the No.5. It was described as the first "safe grenade." They were explosive-filled steel canisters with a triggering pin and a distinctive deeply notched surface. This segmentation is often erroneously thought to aid fragmentation, though Mills' own notes show the external grooves were purely to aid the soldier to grip the weapon.
The Mills bomb underwent numerous modifications. The No. 23 was a variant of the No. 5 with a rodded base plug which allowed it to be fired from a rifle. This concept evolved further with the No. 36, a variant with a detachable base plate to allow use with a rifle discharger cup. The final variation of the Mills bomb, the No. 36M, was specially designed and waterproofed with shellac for use initially in the hot climate of Mesopotamia in 1917, but remained in production for many years. By 1918 the No. 5 and No. 23 were declared obsolete and the No. 36 (but not the 36M) followed in 1932.
The Mills was a classic design; a grooved cast iron "pineapple" with a central striker held by a close hand lever and secured with a pin. The Mills was a defensive grenade: after throwing the user had to take cover immediately. A competent thrower could manage 15 metres (49 feet) with reasonable accuracy, but the grenade could throw lethal fragments farther than this. The British Home Guard were instructed that throwing range of the No. 36 was about 30 yards with a danger area of about 100 yds.
Approximately 75,000,000 grenades were manufactured during World War I and remained in use through to the Second World War. At first the grenade was fitted with a seven-second fuse, but during combat in the Battle of France in 1940, this delay proved too long - giving defenders time to escape the explosion or even to throw the grenade back — so the fuse was reduced to four seconds.
The German Model 24 Stielhandgranate stick grenade was a concussion grenade introduced in 1915 and the design developed throughout World War I. A friction igniter was used; this method was uncommon in other countries but widely used for German grenades.
A pull cord ran down the hollow handle from the detonator within the explosive head, terminating in a porcelain ball held in place by a detachable base closing cap. To use the grenade, the base cap was unscrewed, permitting the ball and cord to fall out. Pulling the cord dragged a roughened steel rod through the igniter, causing it to flare-up and start the five-second fuse burning. This simple design continued to evolve throughout the First and Second World Wars, with the Model 24 grenade (popularly known as the "potato masher") becoming one of the most easily recognized of all small arms, and synonymous with the German soldier.
Towards the end of WWII, the M24 was replaced by the Model 43 grenade. This simplified production by making the handle solid and placing the pull cord on the top of the grenade. The head could also be fitted with a sleeve to change it from a concussion to a fragmentation grenade.
During World War II, the United Kingdom used incendiary grenades based on white phosphorus. One model, the No. 76 Special Incendiary Grenade, was mainly issued to the Home Guard as an anti-tank weapon. It was produced in vast numbers; by August 1941 well over 6,000,000 had been manufactured.
The United States developed the Mk 2 hand grenade prior to the war. Nicknamed the "pineapple" for its grooved surface, this weapon became synonymous with the American G.I. However, the heavy, segmented bodies of "pineapple" type grenades result in an unpredictable pattern of fragmentation. After the Second World War, Britain adopted grenades that contained segmented coiled wire in smooth metal casings. Despite this, the Mills bomb remained the standard grenade of the British Armed Forces and was manufactured in the UK until 1972, when it was completely replaced by the L2 series.
Fragmentation grenades are common in armies. They are weapons that are designed to disperse lethal fragments upon detonation. The body is generally made of a hard synthetic material or steel, which will provide some fragmentation as shards and splinters, though in modern grenades a pre-formed fragmentation matrix is often used. The pre-formed fragmentation may be spherical, cuboid, wire or notched wire. Most AP grenades are designed to detonate either after a time delay or on impact.
When the word grenade is used without specification, and context does not suggest otherwise, it is generally assumed to refer to a fragmentation grenade.
Fragmentation grenades can be divided into two main types, defensive and offensive, where the former are designed to be used from a position of cover, (e.g. in a slit trench or behind a suitable wall,) and have an effective radius greater than the distance it can be thrown, while the latter are for assaulting troops and have a smaller effective fragmentation radius.
Modern fragmentation grenades such as the United States M67 grenade have a wounding radius of 15 m (49 ft) – half that of older style grenades, which can still be encountered – and can be thrown about 40 m (130 ft). Fragments may travel more than 200 m (660 ft)
The concussion grenade is an anti-personnel device that is designed to damage its target with explosive power alone. Compared to fragmentation grenades, the explosive filler is usually of a greater weight and volume, and the case is much thinner - the US MK3A2 concussion grenade, for example, has a body of fiber (similar to the packing container for the fragmentation grenade).
These grenades are usually classed as offensive weapons, because the small effective casualty radius is much less than the distance it can be thrown. The concussion effect, rather than any expelled fragments, is the effective killer. In the case of the US Mk3A2, the casualty radius is published as 2 meters (6–7 feet) in open areas, but fragments and bits of fuse may be projected as far as 200 meters from the detonation point.
In addition to on-land use, they have been used as an anti-personnel depth charge around watercraft—and some, such as the US Mk 40 concussion grenade, are specifically designed for use against enemy divers and frogmen. The Mk 40 kills or otherwise incapacitates the target by creating a lethal shockwave underwater.
A range of hand-thrown grenades have been designed for use against armoured vehicles. An early, fairly weak example was the British Sticky bomb of 1940. Following designs such as the German Panzerwurfmine (L) and the Russian RPG-43, RPG-40, RPG-6 and RKG-3 series of grenades all used a HEAT warhead on one end and some method to stabilize flight and increase the likelihood of the 90 degree hit necessary for the shaped charge to be effective.
Due to improvements in modern tank armor, anti-tank hand grenades are generally considered obsolete. However, in the recent Iraq War, RKG-3 anti-tank hand grenades were successfully used against lightly armored U.S. Humvees, Strykers and MRAPs leading to countermeasures such the fitting of "slat" armor or "bird cage" armor to cause any antitank grenade to detonate early.
A stun grenade, also known as a flash grenade or a flashbang, is a non-lethal weapon. The first devices like this were created in the 1960s at the order of the British Special Air Service as an incapacitant.
It is designed to produce a blinding flash of light and loud noise without causing permanent injury. The flash produced momentarily activates all light sensitive cells in the eye, making vision impossible for approximately five seconds, until the eye restores itself to its normal, unstimulated state. The loud blast causes temporary loss of hearing, and also disturbs the fluid in the ear, causing loss of balance.
These grenades are designed to temporarily neutralize the combat effectiveness of enemies by disorienting their senses.
When detonated, the fuse/grenade body assembly remains intact. The body is a tube with holes along the sides that emit the light and sound of the explosion. The explosion does not cause shrapnel injury, but can still burn. The concussive blast of the detonation can injure and the heat created can ignite flammable materials such as fuel. The fires that occurred during the Iranian Embassy Siege in London were caused by stun grenades. The filler consists of about 4.5 grams of a pyrotechnic metal-oxidant mix of magnesium or aluminium and an oxidizer such as ammonium perchlorate or potassium perchlorate.
Sting grenades are stun grenades based on the design of the fragmentation grenade. Instead of using a metal casing to produce shrapnel, they are made from hard rubber and are filled with around 100 rubber balls. Upon detonation the rubber balls, and shrapnel from the rubber casing, explode outward in all directions as a form of less-lethal shrapnel. These projectiles may ricochet. Any people in the way will receive a series of fast, painful stings. Some types have an additional payload of CS gas.
A disadvantage of using sting grenades is that they are not sure to incapacitate a subject, so they are dangerous to use with armed subjects. In addition, there is the risk of serious physical injury, especially from the rubber shrapnel from the casing.
Chemical and gas grenades include smoke grenades and incendiary grenades. Unlike explosive grenades, chemical and gas grenades are designed to burn or to release a gas, not to explode.
Smoke grenades are used as ground-to-ground or ground-to-air signalling devices, target or landing zone marking devices, and screening devices for unit movement. The body is a sheet-steel cylinder with emission holes in the top and bottom. These allow the smoke to be released when the grenade is ignited. Two main types exist: coloured smoke (for signaling) and screening smoke. In coloured smoke grenades, the filler consists of 250 to 350 grams of coloured smoke mixture (mostly potassium chlorate, lactose and a dye). Screening smoke grenades usually contain HC (hexachloroethane/zinc) smoke mixture or TA (terephthalic acid) smoke mixture. HC smoke is harmful to breathe, since it contains hydrochloric acid. Whilst not intended as a primary effect, these grenades can generate enough heat to scald or burn unprotected skin, and the spent casing should not be touched until it has cooled.
Tear gas grenades are similar to smoke grenades in terms of shape and operation. In tear gas grenades the filler is generally 80 to 120 grams of CS gas combined with a pyrotechnic composition which burns to generate an aerosol of CS-laden smoke. This causes extreme irritation to the eyes and, if inhaled, to the nose and throat. (See also the Waco Siege). Occasionally CR gas is used instead of CS.
Incendiary grenades (or thermite grenades) produce intense heat by means of a chemical reaction. Greek Fire could be considered the earliest form of an incendiary grenade, which could be lit on fire and thrown in breakable pottery. The weapon was first used by the Byzantines.
Modern incendiary grenades (or thermite grenades) produce intense heat by means of a chemical reaction. The body is practically the same as that of a smoke grenade. The filler is 600 to 800 grams of thermate, which is an improved version of World War II-era thermite. The chemical reaction that produces the heat is called a thermite reaction. In this reaction, powdered aluminium metal and iron oxide react to produce a stream of molten iron and aluminium oxide. This reaction produces a tremendous amount of heat, burning at 2,200 °C (3,992 °F). This makes incendiary grenades useful for destroying weapons caches, artillery, and vehicles. Other advantages include its ability to function without an external oxygen source, allowing it to burn underwater. Because they are not intended to be thrown, thermite incendiary grenades generally have a shorter delay fuse than other grenades (e.g. two seconds).
White phosphorus (also used in smoke grenades; see above) can also be used as an incendiary agent. It burns at a temperature of 2,800 °C (5,070 °F). White phosphorus was notably used in the No 76 Special Incendiary Grenade by the British Home Guard during World War II.
Thermite and white phosphorus cause some of the worst and most painful burn injuries because they burn so quickly and at such a high temperature. In addition, white phosphorus is very poisonous: a dose of 50-100 milligrams is lethal to the average human.
The Molotov cocktail is an improvised incendiary grenade prepared from a glass bottle filled with gasoline (petrol) ignited by an attached burning strip of cloth when the thrown bottle bursts against its target. The Molotov cocktail received its name during the Soviet invasion of Finland in 1939 Winter War, but had been in use earlier in the decade when used by Franco's troops during the Spanish Civil War. The name originated from Finnish troops during the Winter War. It was named after former Soviet foreign minister Vyacheslav Molotov whom they deemed responsible for the war, and a humorous reference to the Soviet bombs known as "Molotov bread baskets" in Finland.
Practice grenades are similar in handling and function to other hand grenades, except that they only produce a loud popping noise and a puff of smoke on detonation. The grenade body can be reused. Another type is the throwing practice grenade which is completely inert and often cast in one piece. It's used to give soldiers a feel for the weight and shape of real grenades and for practicing precision throwing.
Various fuses (detonation mechanisms) are used, depending on purpose.
Examples of grenades fitted with impact fuses are the German M1913 and M1915 Diskushandgranate, and any British grenade fitted with the Allways fuse such as the No 69 grenade, No 77 grenade and No 82 grenade (Gammon bomb).
In a timed fuse grenade, the fuse is ignited upon release of the safety lever, and detonation occurs following a timed delay. Timed fuse grenades are generally preferred to hand-thrown percussion grenades because their fusing mechanisms are safer and more robust than those used in percussion grenades.
Fuses are frequently fixed, though the Russian UZRGM (Russian: УЗРГМ) fuses are interchangeable and allow the delay to be varied, or even replaced by a pull fuse. This is potentially dangerous, due to risk of confusion. Standard time delay since World War II (specifically post-Battle of France, 1940) is around 4 seconds, though this varies, with some Soviet fuses having delays as low as 3.2–3.5 seconds, while current US grenades have delays in the 4–5.5 second range; previously the Mills bomb (1915) had had a 7-second fuse, which was found to be too long. UZRGM fuses vary from 0 seconds to 13 seconds.
A pull fuse is a zero-delay fuse used in booby traps: when the striker retaining pin is removed, the grenade is immediately detonated. The pin is typically attached to a tripwire.
Beyond the basic pin-and-lever mechanism, contemporary grenades have a number of safety features. Most notable are the safety clip and the bent end of the safety pin. The safety clip was introduced in the M61 grenade (1960s, Vietnam War), and is also known as the "jungle clip" – this provides a backup for the safety pin, in case it is dislodged, notably by jungle growth. This is particularly important because the safety lever is often used as a carry hook, despite the obvious danger this poses. The bent end of the safety pin increases the force required to remove it, reducing the risk of accidental arming.
More fundamentally, ensuring that fatality and casualty radii are significantly lower than the engagement distance – and distance the grenade can be thrown – and ensuring reliable, predictable detonation and blast radius, minimize the hazard.
Modern manufacturers of hand grenades include:
The classic hand grenade design has a safety handle or lever (known in the US forces as the spoon) and a removable safety pin that prevents the handle from being released: the safety lever is spring-loaded, and once the safety pin is removed, the lever will release and ignite the detonator, then fall off. Thus to use a grenade, the lever is grasped (to prevent release), then the pin is removed, and then the grenade is thrown, which releases the lever and ignites the detonator, triggering explosion. Some grenade types also have a safety clip to further prevent the handle from coming off in transit.
To use a grenade, the soldier grips it with the throwing hand, ensuring that his thumb holds the safety lever in place; if there is a safety clip, it is removed prior to use. Left-handed soldiers are advised to invert the grenade, so the thumb is still the digit that holds the safety lever. The soldier then grabs the safety pin's pull ring with the index or middle finger of the other hand and removes it. He then throws the grenade towards the target. Soldiers are trained to throw grenades in standing, prone-to-standing, kneeling, prone-to-kneeling, and alternate prone positions and in under- or side-arm throws. If the grenade is thrown from a standing position the thrower must then immediately seek cover or lie prone if no cover is nearby.
Once the soldier throws the grenade, the safety lever releases, the striker throws the safety lever away from the grenade body as it rotates to detonate the primer. The primer explodes and ignites the fuse (sometimes called the delay element). The fuse burns down to the detonator, which explodes the main charge.
When using an antipersonnel grenade, the objective is to have the grenade explode so that the target is within its effective radius. The M67 frag grenade has an advertised effective kill zone of five meter radius, while the casualty-inducing radius is approximately fifteen meters. Within this range, people are generally injured badly enough to effectively render them harmless. However, these ranges only indicate the area where a target is virtually certain to be incapacitated; individual fragments can still cause injuries as far as 230 meters away.
An alternative technique is to release the lever before throwing the grenade, which allows fuse to burn partially and decrease the time to detonation after throwing; this is referred to as cooking. A shorter delay is useful to reduce the ability of the enemy to take cover or throw the grenade back, and can also used to allow the grenade to burst in the air over defensive positions. This technique is inherently dangerous, due to shorter delay (hence closer explosion), greater complexity (must make sure to throw after waiting), and increased variability (fuses vary from grenade to grenade, and waiting increases the overall variability in delay), and thus is discouraged in the U.S. Marine Corps, and banned in training.
Tactics vary by type of engagement. Urban warfare, particularly attack of built-up areas, involves heavy use of hand grenades: typically a grenade or two is thrown before each transition (such as entering a room or negotiating a stairway), and a World War II battalion fighting in a city frequently used 500 grenades per day.
A key concern is that the grenade is not picked up and thrown back. The USMC preferred technique to prevent this is a hard-throw, skip/bounce technique, where the grenade is thrown hard enough that it bounces or skips around, being hard to pick up and throw back – this is applicable when clearing a room, for instance. In other uses, such to reach upper floors of a building, a grenade may be lobbed for greater distance or accuracy.
Throwing a grenade up stairs is dangerous, due to the risk of it falling back down; it is much safer to throw a grenade down stairs, so it is safer to capture a building from the top, rather than the bottom . Further, grenades generally explode near the floor, causing spalling downwards towards lower floors.
The preferred technique when attacking is to show the grenade to fellow friendly forces, receiving a visual acknowledgement, to avoid alerting the enemy. Alternatively, a voice alert can be given immediately after throwing the grenade, shouting "frag out" (for "fragmentation grenade outgoing") or (in case of dropping a grenade into an enclosed space), fire in the hole – however, this reduces or eliminates the element of surprise. Conversely, on identifying an incoming enemy grenade, friendly forces shout "grenade".
Grenades have often used in the field to construct booby traps, using some action of the intended target (such as opening a door, or starting a car) to trigger the grenade. These grenade-based booby traps are simple to construct in the field as long as instant fuzes are available; a delay in detonation can allow the intended target to take cover. The most basic technique involves wedging a grenade in a tight spot so the safety lever does not leave the grenade when the pin is pulled. A string is then tied from the head assembly to another stationary object. When a soldier steps on the string, the grenade is pulled out of the narrow passageway, the safety lever is released, and the grenade detonates.
Abandoned booby traps and discarded grenades contribute to the problem of UXO. The use of target triggered grenades and AP mines is banned to the signatories of the Ottawa Treaty and may be treated as a war crime wherever it is ratified. Many countries including India, the People's Republic of China, Russia, and the United States have not signed the treaty citing self-defense needs.
Grenades have also been made to release smoke, tear gas and other gases, as well as illumination. Stun grenades are often used to disorient people during entry into a room, especially where hostages or non-combatants may be present.
Some grenades are designed to be thrown longer distances. The German "potato-masher" grenade had a long wooden handle that extended its range by fifty percent. The potato-masher was fired by a friction igniter in the head, activated by a pull string threaded through the hollow handle. Immediately before throwing the grenade, the soldier pulled a small porcelain ball at the end of a string attached to the friction igniter. This started the time fuse, which fired the detonator after a delay. The potato-masher is often incorrectly thought to have had an impact fuse. It did not, but the superficially similar British stick grenade design of 1908 did.
Concussion grenades can also be used as general explosives, for instance for demolition.
Media portrayals of hand grenade use are frequently inaccurate or misleading, due to ignorance of actual function or for dramatic effect.
Common issues include:
Stylized pictures of early grenades, emitting a flame, are used as ornaments on military uniforms, particularly in Britain, France (esp. French Gendarmerie and the French Army), and Italy (Carabinieri). Fusilier regiments in the British and Commonwealth tradition (e.g., the Princess Louise Fusiliers, Canadian Army) wear a cap-badge depicting flaming grenade, reflecting their historic use of grenades in the assault. The British Grenadier Guards took their name and cap badge of a burning grenade from repelling an attack of French Grenadiers at Waterloo. The Spanish artillery arm uses a flaming grenade as its badge. The flag of the Russian Ground Forces also bears a flaming grenade device. Ukrainian mechanized infantry and engineers use a flaming grenade in their branch insignia. The Finnish Army Corps of Engineers' emblem consists of a stick hand grenade (symbolizing demolition) and a shovel (symbolizing construction) in saltire.
The branch insignia of the U.S. Army Ordnance Corps also uses this symbol, the grenade being symbolic of explosive ordnance in general. The United States Marine Corps uses the grenade as part of the insignia for one officer rank and one Staff NCO rank on their uniforms. Chief Warrant Officers designated as a Marine Gunner replace the rank insignia worn on the left collar with a "Bursting Bomb" and a larger "Bursting Bomb" insignia is worn 3/4" above the rank insignia on both shoulder epaulets when a coat is worn. Additionally, the rank insignia for Master Gunnery Sergeant has three chevrons pointing up, with four rockers on the bottom. In the middle of this is a bursting bomb, or grenade. U.S. Navy Aviation Ordnanceman's rating badge features a winged device of similar design.
In the United States, grenades are classed as destructive devices, a form of Title II weapons under the National Firearms Act. They thus must be registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives and are taxed; further, they are illegal in some states (which ban Title II weapons). While in principle it is possible to legally obtain and own hand grenades in some states, in practice they are not generally legal or available.
First known illustration of a fire lance and a grenade
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