Hand grenade

M67 fragmentation grenade, a widely used modern hand grenade.

A hand grenade is any small bomb that can be thrown by hand. Hand grenades are classified into three categories, explosive grenades, chemical and gas grenades.^[1] Explosive grenades are the most commonly used in modern warfare, and are designed to detonate after impact or after a set amount of time. Chemical and gas grenades are designed not to explode, but to burn or release a gas.^[1]

Grenadiers were originally soldiers who specialized in throwing grenades.

Etymology

"Small explosive shell", 1590s, from Modern French grenade, meaning "pomegranate", and from Old French pomegrenate (influenced by Spanish granada). So called because the many-seeded fruit suggested the powder-filled, fragmenting bomb, or from similarity of shape.^[2]

Chemical and gas grenades

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.^[1]

M18 smoke grenade		M7A2 CS gas grenade

Smoke

Main article: Smoke grenade

Smoke grenades are used as ground-to-ground or ground-to-air signaling 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, colored smoke (for signaling) and screening smoke. In colored smoke grenades, the filler consists of 250 to 350 grams of colored 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.

Riot control

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 grenade

Incendiary

Main article: Incendiary device

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.

A common improvised incendiary grenade is the Molotov cocktail.

History

See also: Early thermal weapons

Byzantine Empire

The first incendiary grenades appeared in the Eastern Roman (Byzantine) Empire, not long after the reign of Leo III (717-741).^[3] 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.^[3] Later, glass containers were employed. Byzantine hand grenades with Greek fire in the 10th to 12th centuries are on display in the National Museum at Athens. 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.^[3]

Hand grenades filled with Greek fire; surrounded by caltrops. (10th-12th c. National Historical Museum, Athens, Greece)

World War II

During World War II, the United Kingdom used incendiary grenades based on white phosphorus. The grenade, called 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.^[4]

The grenade could either be thrown by hand, or fired from the Northover projector, a simple mortar; a stronger container was needed for the latter and the two types were colour-coded. As any breakage of the flask would be dangerous, storage under water was recommended.

Molotov cocktail

The Molotov cocktail is an improvised incendiary grenade prepared from a glass bottle filled with gasoline (petrol) ignited by a 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.

Explosive grenades

Explosive grenades are designed to detonate after impact or after a set amount of time.^[1]

Fragmentation

Main article: Fragmentation grenade

The fragmentation grenade (commonly known as a frag) is an anti-personnel weapon that is designed to disperse shrapnel upon exploding. The body is made of hard plastic or steel. Flechettes, notched wire, ball bearings or the case itself provide the fragments. When the word grenade is used without specification, and context does not suggest otherwise, it is generally assumed to refer to a fragmentation grenade.

These grenades were sometimes classed as defensive grenades because the effective casualty radius of some matched or exceeded the distance they could be thrown, thus necessitating them being thrown from behind cover. The Mills bomb or F1 grenade are examples of defensive grenades where the 30–45 m casualty radius^[5] matched or exceeded the 30 m that a grenade could reasonably be thrown.

Modern fragmentation grenades such as the United States M67 grenade have a wounding radius of 15 m (half that of older style grenades, which can still be encountered) and can be thrown about 40 m. Fragments may travel more than 200 m.^[6]

Concussion

US sailor undergoing grenadier certification with a concussion grenade

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. The case is far thinner and is designed to fragment as little as possible. The overpressure produced by this grenade when used in enclosed areas is greater than that produced by the fragmentation grenade. Therefore, it is especially effective in enclosed areas.

Thousands of concussion grenades were dropped into the rivers of Vietnam by sailors of the Brown Water boats. Landing Craft Utility (LCU) or Yard Freight Utility (YFU) boats always kept several cases of concussion grenades aboard to discourage sapper teams from swimming down the river and attaching or placing mines under the boats. Patrol Boat River (PBR) and other armed river boats could provide some sentry protection above water, but concussion grenades could disable an enemy approaching underwater. A swimmer would be immediately disabled by breaking ear drums and blood vessels in the eyes if within range of the concussion grenade. Common practice was to drop concussion grenades all night at irregular times (four or five per hour) to discourage swimmers from timing the interval between drops.

These grenades are usually classed as offensive weapons because the effective casualty radius is smaller than the distance it can be thrown on land. The concussion effect is more lethal than fragmentation, but its power drops more rapidly with range on land as well. The effective range to disable a swimmer under water in a shallow river is about 10-20 meters.

The US MK3A2 concussion grenade is filled with TNT and has a body made of tarred cardboard. It came with a "spoon" on the top—a spring-loaded arming device that was activated by pulling a ring on a cotter pin that held the spoon to the grenade's side. Once the pin was removed, the thrower had to keep the spoon in place by holding it against the grenade. Once the spoon was released, the spring flipped it away from the grenade and a timed fuse chemical reaction started that would usually set the grenade off within four seconds. Holding the grenade to the count of two might be an advantage over tossing it overboard immediately into shallow water. If the concussion grenade sank to the bottom and penetrated into the mud, it was less effective than detonating at the depth that an enemy sapper would be swimming.

The term concussion is often erroneously applied to stun grenades. This is not descriptive of the effects caused by the grenade. The term concussion is used because the grenade relies on its explosive power to create casualties. The Mk 40 is a TNT filled concussion grenade specifically for use against enemy divers and frogmen. The grenade is designed to be employed essentially as an anti-personnel depth charge, killing or otherwise incapacitating the target by creating a lethal shockwave underwater, similar to that of a full-size depth charge.^[7]

Anti-tank

Main article: Anti-tank grenade

Soviet RPG-43 antitank grenade schematic showing armor defeating shaped charge

The first anti-tank grenades were improvised devices. The Germans were the first during World War I to come up with an improvised anti-tank grenade, taking their "potato masher" and taping two to three more of the explosive heads without the handle to create one complete grenade. In combat, after arming, the grenade was lobbed on top of the vehicle where the armor was thin.

During World War II, various nations made improvised anti-tank grenades by putting a number of defensive high explosive grenades into a sandbag. Due to their weight, these were normally thrown from very close range or directly placed in vulnerable spots onto an enemy vehicle.^{[citation needed]} Another method used by the British Home Guard in 1940 was to place a high explosive in a thick sock and cover the lower part with axle grease and then place the grease covered part in a suitable size tin can. The anti-tank sock was pulled out, the fuse lit and the sock thrown against the side of the vehicle where it would adhere until the explosion. It caused internal spalling of the armor plate, killing or injuring the tank crew inside.^[8] By late 1940, the British had brought into production a purpose-built adhesive anti-tank grenade - known as the sticky bomb.^[9]

During World War II, when tanks overran entrenchments, hand grenades could be and were used by infantry as improvised anti-tank mines by placing or throwing them in the path of a tank in the hope of disabling a track. While this method was used in desperation, it usually proved more dangerous to the soldier on the ground than to the crew of the tank.

Purpose-designed anti-tank grenades invariably use the shaped charge principle to penetrate tank armor. In military terminology, warheads employing shape charges are called high explosive anti-tank (HEAT) warheads. Because of the way shaped charges function, the grenade must hit the vehicle at an exact right angle for the effect to work most efficiently. The grenade facilitates this by deploying a small drogue parachute or fabric streamers after being thrown.

Britain developed the No 74 ST Grenade, popularly known as a sticky bomb, in which the main charge was held in a sphere covered in adhesive. In anticipation of a German invasion, the British Army asked for ideas for a simple, easy to use, ready for production and cheap close-in antitank weapon. The ST Grenade was a government sponsored initiative, by MIR(c), a group tasked with developing weapons for use in German and Italian occupied territory, and they placed the ST Grenade into mass production at Churchill's insistence, but seeing how it was operated, the British Army rejected it for the Home Guard much less their regular forces. The No 74 Grenade was later issued to troops as an emergency stop-gap measure against Italian tanks in North Africa, where it proved—to the surprise of many—highly effective. Later in the war, French partisans used the No 74 effectively in sabotage work against German installations.^[10]

Shortly after the German invasion of Russia in 1941, the Germans introduced the Panzerwurfmine(L), a HEAT grenade that could destroy even the heaviest tanks. The grenade was tossed overhand to land atop the tank. After release by the thrower, spring-out canvas fins stabilized it during its short flight. The Panzerwurfmine(L) was lethal, and inexpensive to manufacture, but required considerable skill to throw accurately and was issued only to specially trained infantry tank-killer teams.^[11] It did not take long after the Russians captured the German Panzerwurfmine(L) to come out with their own HEAT grenade. In 1940, they developed a crude anti-tank grenade that used the simple blast effect of a large high explosive charge, designated RPG-40, which was stabilized in flight by a ribbon released after it was thrown.^[12] The RPG-43 of 1943 was a modified RPG-40 with a cone liner and a large number of fabric ribbons for flight stabilization after release. In the last year of the war, they introduced the RPG-6, a total redesign of the RPG-43 with an improved kite-tail drogue in the handle and a standoff for the HEAT warhead, drastically increasing both accuracy and penetration causing catastrophic damage to any tank if it impacted the top. The Russian RPG-43 and RPG-6 were far simpler to use in combat than the German Panzerwurfmine(L)and did not require extensive training.

After the end of World War II, many eastern European nations engineered their own versions of the RPG-6, such as the East German AZ-58-K-100. These were manufactured in the tens of thousands and given to 'armies of national liberation', seeing combat worldwide, including with the Egyptian Army during 1967 and 1973.^[13][14][15]

In the final two years of World War II, the Japanese developed a crude HEAT hand grenade. The grenade had a simple 100 mm diameter cone HEAT warhead with a simple "all the way" fuse system in the base. It had what looked like the end of a mop head on the tail end of the warhead. A soldier would remove the anti-tank grenade from its sack, pull the pin, and throw it gripping the mop-head as the handle. This was dangerous, as there was no arming safety after release. Penetration was reported only around 50mm.^{[citation needed]}

In the late 1970s, the U.S. Army was worried about the lack of emergency anti-tank weapons for issue to its rear area units, to counter isolated enemy armored vehicles infiltrating or being air dropped. When the US Army asked for ideas, engineers at the U.S. Army laboratories suggested designing a derivative of the East German AZ-58-K-100 HEAT antitank grenade. This concept was called "HAG" for High-explosive Anti-armor Grenade. While the civilian engineers working for the US Army thought it was a great idea, it was rejected out of hand by almost all senior US Army officers who had in the past commanded troops in the field as being more dangerous to the troops who used them than the enemy vehicles that would be targeted, so, the idea was shelved by 1985.^[16][17]

The most widely-distributed anti-tank grenades today are the Cold War era Russian designs of the 1950s and 1960s, mainly the RKG-3.

Due to improvements in modern tank armor, anti-tank hand grenades are generally considered obsolete. However, in the recent Iraq War, the RKG-3 made a reappearance with Iraqi insurgents who use them primarily against U.S. light vehicles. This has led the U.S. to apply additional armor.^[18]

History

See also: History of gunpowder

China

Earliest known representation of a gun (a fire lance) and a grenade (upper right), Dunhuang, 10th century CE.^[19]

In China during the Song Dynasty (960–1279AD), weapons known as Zhen Tian Lei 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.^[20]

The first cast iron bombshells and grenades did not appear in Europe until 1467.^[21] Within a couple centuries of this, the Chinese had discovered the explosive potential of packing hollowed cannonball shells with gunpowder. Written later by Jiao Yu (焦玉) in the mid 14th century book of the Huolongjing (火龙经, "Fire Drake Manual"), this manuscript 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...

—^[22]

This text of the Huolongjing was also important for the understanding of the Chinese hand grenade in the 14th century, as it provided much more detailed descriptions and even printed illustrations of the grenade bombs used.^[23]

Production of Sidolówka hand grenades in an underground Armia Krajowa facility in Lwów during World War II.

Europe

In 1643, it is possible that "Grenados" were thrown amongst the Welsh at Holt Bridge during the English Civil War. The word "grenade" originated in the Glorious Revolution (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.^[24] 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.

French troops using a catapult to throw hand grenades during World War I.

However, trench warfare favored the grenade. In a letter to his sister, Colonel Hugh Robert Hibbert, described an improvised grenade employed during the Crimea War (1854–1856):

{{quote|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.^[25]

American Civil War

In the American Civil War, both sides used hand grenades equipped with a plunger that detonated the device upon impact. The North 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.

1900s

One of the first widely used percussion hand grenades was designed about 1903 by a colonel of the Serbian army, Miloš Vasić. In 1912, Colonel Vasić further redesigned his hand grenade into "Vasić" M.12 model. They were adopted by the Serbian army in 1912, just in time to be used in the 1st and 2nd Balkan War (1912–1913) and extensively used by Serbian infantry in World War I.^[26] That grenade was popular under name of "Vasićka" (by its designers name), or "Kragujevka" (by its place of manufacture, the military-technical works in Kragujevac, Serbia). The Vasić design was further developed into a series of new hand grenades that lasted until far after the end of World War II.^[27]

The most infamous employment of the "Vasić" hand grenade occurred not long before the assassination of Archduke Franz Ferdinand in Sarajevo in 1914, when a conspirator threw one at the Archduke's car. The grenade bounced off and exploded under a following vehicle, wounding about 20 people. Franz Ferdinand and his wife were shot to death by another conspirator later that day. Austro-Hungarian authorities confiscated a couple of "Vasić" grenades from would-be assassins, using them to support accusations that Serbia was a participant in the murderous plot—the act that led to the outbreak of WWI.^{[citation needed]}

World War I

Section of the Stielhandgranate Modell 24

Early in World War I, both sides only had small grenades of a pre-war design. For example, in Italy, the Besozzi grenade had a five-second fuse with a match-tip that was ignited by striking on a ring on the soldier's hand.^[28] As an interim measure, the troops often improvised their own, such as the Jam Tin Grenade. These were replaced when manufactured versions such as the Mills bomb, the first modern fragmentation grenade, became available to British front-line troops.

Mills bomb

Main article: Mills bomb

36M Mills bomb from 1942

The Mills bomb was developed at the Mills Munitions Factory in Birmingham, England and was described as the first "safe grenade." Approximately 75,000,000 grenades were made during World War I. They were explosive-filled steel canisters with a triggering pin and a distinctive deeply notched surface. This segmentation was thought to aid fragmentation and increase the grenade's deadliness. Later research showed that the segmentation did not improve fragmentation. Improved-fragmentation designs would later be made with the notches on the inside, but at the time, this would have been too expensive to produce. The external segmentation of the original Mills bomb was retained, since it did provide a positive grip surface. This basic "pin-and-pineapple" design is still used in some modern grenades. On the other hand, the U.S. M67 fragmentation grenade has a smooth exterior, which is more suitable for being rolled or for throwing in a flat arc.

George Orwell in Homage to Catalonia^[29] used the word “bomb” to denote hand grenades used during 1936-37 trench warfare when he was a militia soldier in the Spanish Civil War. He noted their similarity to the "Mills bomb" [see above]. Only once did he use the word “hand-grenade", describing street fighting in Barcelona, May 1937:

“The din was so loud that I made sure someone must be firing at us with a field gun. Actually it was only hand-grenades, which made double their usual noise when they burst among stone buildings.”^[30]

Parallel to the Mills bomb and its similar counterparts, the Germans issued the "stick hand grenade" (Stielhandgranate Modell 24), which featured an explosive charge encased in a metal can and mounted on a wooden shaft for throwing. 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.

Design

Hand grenade fuse system		Modern Israeli grenade cutaway. Note the lack of ball-bearing and explosive filler in the practice grenade (right).

French F1 percussion grenade

Most grenades explode, projecting shrapnel, i.e., pieces of the casing, serrated wire, or an incendiary material. Some, such as smoke grenades, merely burn, releasing smoke for masking, marking, or signaling. CS riot grenades function the same way. Grenades contain an explosive or chemical filler and have a small opening for a fuse. In modern hand grenades, the fuse is lit by an internal device rather than an external flame.

Hand grenades have five characteristics:

• Short range
• Small effective kill radius, roughly 8 meters
• Large effective casualty radius, roughly 15 meters
• Delay element that permits safe throwing
• Hard shell that lets them ricochet off hard surfaces, like walls, before detonating

Hand grenades have:

• A body that contains the filler
• A filler, the chemical or explosive for fragmentation
• A fuse that ignites or detonates the grenade

Detonation mechanism

Percussion

A percussion grenade detonates upon impact with the target. Classic examples of percussion grenades are the British Gammon bomb and No 69 grenade. Some percussion grenades have a conventional pyrotechnic fuse fitted as a backup detonation device.

Timed fuse

In a timed fuse grenade, the fuse is ignited upon release of the safety lever. Timed fuse grenades are generally preferred to hand-thrown percussion grenades because their fuzing mechanisms are safer and more robust than those used in percussion grenades.

Manufacturing

Modern manufacturers of hand grenades include:

• Diehl ^[31] (Germany)
• Mecar ^[32] (Belgium)
• Rheinmetall ^[33] (Germany, formerly Arges, Austria)
• Ruag ^[34] (Switzerland)

Using grenades

1944: An American soldier throwing a live "pineapple" hand grenade at the training range of Fort Belvoir

2005: U.S. Army grenade training during initial entry training includes throwing both dummy and live hand grenades, range instructor at right observes an M67 grenade in flight. The Grenade as well as the safety lever can be seen

A classic hand grenade has a safety handle or lever (known colloquially as the spoon, due to its size and shape) and a removable safety pin that prevents the handle from being released. 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. This is called the death grip, because releasing the lever could (and probably would) make the grenade detonate, killing the thrower. 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 with a pulling and twisting motion. He then throws the grenade towards the target. An over-arm throw is recommended but may not be suitable for every combat situation. 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. For the M67 fragmentation grenade used by several NATO nations, the effective kill zone has a five meter radius, while the casualty-inducing radius is approximately fifteen meters.^[35] Fragments can fly as far as 230 meters. Usually people in a 15 meter radius are injured enough to effectively render them harmless.

Cooking off is a term referring to intentionally holding onto an armed grenade after the pin has been pulled and the handle released; allowing the fuse to burn partially to decrease the time to detonation after throwing. This technique is used to reduce the ability of the enemy to take cover or throw the grenade back. It is also used to allow the grenade to burst in the air over defensive positions.^[36] This technique is inherently dangerous, since fuses may vary from grenade to grenade. Because of this the U.S. Marines (MCWP 3-35) describe cooking-off as the "least preferred technique," recommending a "hard throw, skip/bounce technique" to prevent an enemy returning a grenade.

A call is usually given upon deploying a grenade, to warn friendly forces. Some yells, such as frag out or fire in the hole, signal that a grenade has been deployed. In any instance the purpose is to warn fellow soldiers to take cover. In the U.S. Military, when a grenade is dropped into an enclosed space like a tunnel, room, or trench, the person dropping the grenade yells fire in the hole to warn that an explosion is about to occur. Standard U.S. military procedure includes calling frag out to indicate that a fragmentation grenade has been deployed. Yelling the word "Grenade!" is used to warn others to seek cover from an enemy grenade that has landed in the immediate vicinity.

Grenades are 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 using readily available materials. 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.

Discarded RGD-5 hand grenade (live but unfuzed) in Northern Kuwait

Abandoned booby traps and discarded grenades contribute to the problem of unexploded ordnance. The use of trip wire-triggered grenades (along with land mines in general) is banned under the Ottawa Treaty and may be treated as a war crime wherever it is ratified. India, the People's Republic of China, Russia, and the United States have not signed the treaty despite international pressure, citing self-defense needs.

Grenades have also been made to release smoke, tear gas and other gases, as well as illumination. Special forces often use stun grenades to disorient people during entry into a room.

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.^{[citation needed]} 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.

Other variants

Stun

M84 stun grenade

Main article: Stun grenade

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.

These grenades are designed to temporarily neutralize the combat effectiveness of enemies by disorienting their senses. The flash of light 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 extremely loud blast produced by the grenade adds to its incapacitating properties by disturbing the fluid in the ear.

IDF stun grenade

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

Sting grenades (also called rubber ball grenades or hornet's nest grenades) are based on the design of the fragmentation grenade. But instead of using a metal casing to produce shrapnel, they are made from two spheres of hard rubber. The smaller, inner sphere houses the explosive charge, primer, and detonator, and the outer sphere is the grenade casing. The space between the two spheres is filled with many small, hard rubber balls. Upon detonation the rubber balls explode outward in all directions, each one packing a sting. The balls bounce off hard surfaces so can appear to come from all sides, and can thus be likened to a swarm of hornets. Any people in the way will receive a series of fast, painful stings. The subject is forced to take cover from the blunt force of the projectiles. Some types have an additional payload of chemical agents like CS gas.

The advantages compared to a flashbang are:

• The subject does not need to be looking at the grenade for it to take full effect in outdoor areas.
• Sting grenades are much more likely to cause a subject to either fall or lower themselves in pain, thus providing good sight lines to unaffected targets in the area.

This makes sting grenades ideal for containing small groups of rowdy prisoners, providing a shooting opportunity when a suspect is hiding behind cover, or in allowing SWAT teams to clear small rooms.

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. This is because sting grenades rely on the body's reaction to adverse stimuli (pain and blunt force trauma) rather than denial of sensory input. A person with sufficient mental focus can concentrate enough to ignore being hit by a sting grenade's payload, whereas a stun grenade will physically affect vision and sense of orientation. The effective range of a sting grenade is limited compared to a stun grenade. In addition, there is the risk of serious physical injury as the target is being pelted with actual objects capable of inflicting harm, and not just being deafened/blinded.^{[clarification needed]}

Sting grenades are sometimes called "stinger grenades," which is a genericized trademark as "Stinger" is trademarked by Defense Technology for its own line of sting grenades.

Impact stun

A more recent development is the blank-firing impact grenade (BFIG). Preferred in many situations, especially training, for two main reasons; they are re-usable, and therefore more economical, because the charge is a standard ammunition blank, and they are subject to very few transport restrictions when unloaded. The BFIG contains a mechanism to fire a blank cartridge when dropped at any angle onto a hard surface from a height of a metre or more. Firing will occur in any combination of positions only on impact.^[37]

Grenades as ornamentation

Grenade on a kepi of the French Army

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. 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 also uses the grenade on their uniforms: 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. 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.

See also

• Nils Waltersen Aasen, the creator of the modern hand grenade
• Rocket-propelled grenade
• Rifle grenade
• Grenade launcher
• Satchel charge
• Technology of the Song Dynasty

References

Notes

1. ^ ^{a b c d} "Grenade". Encyclopedia Britannica.
2. ^ http://www.etymonline.com/index.php?term=grenade
3. ^ ^{a b c} Robert James Forbes: "Studies in Ancient Technology," Leiden 1993, ISBN 978-90-04-00621-8, p.107
4. ^ Northover Projectors - WO 185/23, The National Archives
5. ^ (Ukrainian) [1]
6. ^ Federation of American Scientists. M67 FRAGMENTATION HAND GRENADE
7. ^ Dockery 1997, p. 188.
8. ^ A 1941 issue of LIFE magazine showed a series of photo on how to make such antitank grenades along with X shaped slit trenches to protect the grenade thrower
9. ^ Ian Hogg "Grenades & Mortars" page 38 Ballantine Books 1974
10. ^ Ian Hogg "Grenades & Mortars" page 39 Ballantine Books 1974
11. ^ Chris Bishop "Weapons of World War II" page 207-208 Barnes and Nobles Books 1998
12. ^ Denis H.R. Archer "Jane's Infantry Weapons" page 462
13. ^ Chris Bishop "Weapons of World War II" page 214 Barnes and Nobles Books 1998
14. ^ Denis H.R. Archer "Jane's Infantry Weapons" page 464-465
15. ^ Note - see the External Images on the HAG in the "Anti-tank" section of this article for a detail drawings and how Russian anti-tank grenades operate
16. ^ Eric C. Ludvigsen "Association of the United States Army GREEN BOOK 1984-85" page 348
17. ^ As this type of anti-tank grenade had been successfully employed by other armies in the Second World War, one can only conclude that cultural factors influenced the decision of the senior officers. As it was, the decision left many rear-area U.S. units with no heavier "anti-tank weapon" than the M2 heavy machine gun.
18. ^ Schogol, Jeff (October 20, 2009) "MRAPs modified to deflect RKG-3 anti-tank grenades". Stars and Stripes (newspaper)
19. ^ "The Genius of China," Robert Temple
20. ^ Joseph Needham: Science and civilization in China: Vol. 5; Part 6: Chemistry and chemical technology; Military technology: missiles and sieges, Cambridge University Press 1994, ISBN 0-521-32727-X
21. ^ Needham, Volume 5, Part 7, 179.
22. ^ Needham, Volume 5, 264.
23. ^ Needham, Volume 5, Part 7, 179-180.
24. ^ Cramb, Auslan (23 Feb 2004). "Battlefield gives up 1689 hand grenade". Scotland Correspondent. http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2004/02/23/ngren23.xml&sSheet=/news/2004/02/23/ixhome.html. 
25. ^ "The National Archives, records of the UK government". Letters of Hibbert, Hugh Robert, 1828-1895, Colonel, ref. DHB/57 - date: 14 June 1855. http://www.a2a.org.uk/search/records.asp?cat=017-dhb&cid=3-1-3#3-1-3. Retrieved 2006-08-09. 
26. ^ "Istorijat". Zastava-arms.co.yu. http://www.zastava-arms.co.rs/english/zastava.htm. Retrieved 2008-12-26. ^{[dead link]}
27. ^ LEXPEV. "Yugoslavian hand- and riflegrenades". Lexpev.nl. Archived from the original on 2008-08-04. http://web.archive.org/web/20080804042526/http://www.lexpev.nl/grenades/sovietbalkan/yugoslavia/index.html. Retrieved 2008-12-26. 
28. ^ How the Modern Grenadier is Armed: an ancient practice that was revived by the trench fighting of the great war, Popular Science monthly, January 1919, page 14, Scanned by Google Books: http://books.google.com/books?id=HykDAAAAMBAJ&pg=PA14
29. ^ Pub. 1952; cf. Chap VII
30. ^ ibid. Chap. X, p128
31. ^ http://www.janes.com/articles/Janes-Infantry-Weapons/Diehl-DM-51-offensive-defensive-hand-grenade-Germany.html
32. ^ http://www.mecar.be/content.php?langue=english&cle_menus=1156765274
33. ^ http://www.rheinmetall-defence.com/index.php?fid=3313&lang=3
34. ^ http://www.ruag.com/en/Ammotec/Defence_and_Law_Enforcement/Handgranades/HG_85-Linie
35. ^ United States Army Field Manual 3-23.30, Grenades and Pyrotechnic Signals (2005 revision), page 1-6
36. ^ United States Army Field Manual 3-23.30, Grenades and Pyrotechnic Signals (2005 revision), pages 3-11 to 3-12
37. ^ "Impact Stun Grenade from HFM Pyrotechnics:". Hfmgroup.com. http://www.hfmgroup.com/professionalsupplies/product-specs/impact-grenade.html. Retrieved 2008-12-26. 

Bibliography

• Needham, Joseph (1986). Science and Civilization in China: Volume 5, Part 7. Taipei: Caves Books, Ltd.

External links

• Getting Good With the Grenade - November 1944 Popular Science article with complete history, cutaway and illustrations
• Mecar - Belgian manufacturer of various grenade types
• Pakistan Ordnance Factories - licensed manufacturer of Arges grenades
• Film of exploding grenade - taken using ultra high-speed photographic technique (2/3 million frames per second)
• How Grenades Work - from HowStuffWorks
• CenturioLight c/o Centurio Products Group - manufacturer of the electronic flashbang's "BAD"
• Exploded view of a modern Arges 73 hand grenade
• Accidental hand grenade blast injuries in the Transkei region of South Africa: A case report - (WARNING: graphic content)