LEDE SECTION

Fragmentation grenades ("frags") are probably the most common in modern armies, and when the word grenade is used in everyday speech, it is generally assumed to refer to a fragmentation grenade.^{[citation needed]}

History

Gunpowder

The mid-14th-century book Huolongjing (火龍經, Fire Dragon Manual), written by Jiao Yu (焦玉), recorded an earlier Song-era cast-iron cannon known as the "flying-cloud thunderclap cannon" (飛雲霹靂炮; feiyun pili pao). The manuscript stated that (Needham's modified Wade-Giles spelling):

In the American Civil War, both sides used hand grenades equipped with a plunger that detonated the device on impact. The Union relied on experimental Ketchum Grenades, which had a tail to ensure that the nose would strike the target and start the fuze. The Confederacy used spherical hand grenades that weighed about 6 lb (2.7 kg), sometimes with a paper fuze. They also used 'Rains' and 'Adams' grenades, which were similar to the Ketchum in appearance and mechanism.

Development of modern grenades

As an interim measure, troops often improvised their own grenades, such as the jam tin grenade.^{[citation needed]}

Fragmentation grenade

Improvised grenades were replaced when manufactured versions became available. The first modern fragmentation grenade was the Mills bomb, which became available to British front-line troops in 1915.^{[citation needed]}

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, and 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.^{[citation needed]}

The Mills had a grooved cast-iron "pineapple" with a central striker held by a close hand lever and secured with a pin. A competent thrower could manage 15 m (49 ft) with reasonable accuracy, but the grenade could throw lethal fragments farther than this; after throwing, the user had to take cover immediately. The British Home Guard was instructed that the throwing range of the No. 36 was about 30 yd (27 m) with a danger area of about 100 yd (91 m).

Approximately 75,000,000 grenades were manufactured during World War I, used in the war and remaining in use through to the Second World War. At first, the grenade was fitted with a seven-second fuze, but during combat in the Battle of France in 1940, this delay proved too long, giving defenders time to escape the explosion or to throw the grenade back, so the delay was reduced to four seconds.^{[citation needed]}

The F1 grenade was first produced in limited quantities by France in May 1915. This new weapon had improvements from the experience of the first months of the war: the shape was more modern, with an external groove pattern for better grip and easier fragmentation. The second expectation proved deceptive, as the explosion in practice gave no more than 10 fragments (although the pattern was designed to split into all the 38 drawn divisions). The design proved to be very functional, especially due to its stability compared to other grenades of the same period. The F1 was used by many foreign armies from 1915 to 1940.^{[citation needed]}

Stick grenade

Stick grenades have a long handle attached to the grenade proper, providing leverage for longer throwing distance, at the cost of additional weight.^{[citation needed]}

The British introduced their No. 1 grenade in 1908. It had been designed on reports of Japanese weapons used in the Russo-Japanese war. The handle was very long and a streamer tied to the end was used to ensure the fuse hit the ground properly.^{[citation needed]}

The term "stick grenade" is commonly associated with the German Stielhandgranate introduced in 1915 and developed throughout World War I. A friction igniter was used; this method was uncommon in other countries but widely used for German grenades.^{[citation needed]}

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 spark and start the five-second fuze burning. This simple design (popularly known as the "potato masher") continued to evolve throughout the First and Second World Wars, with the Model 24 grenade becoming one of the most easily recognized of all German small arms. The German Model 43 grenade was a low-cost version introduced late in the war.^{[citation needed]}

Other stick grenades were made, including the Russian RGD-33 and Model 1914 grenades, and the British sticky bomb.^{[citation needed]}

Further development

The United States developed the Mk 2 hand grenade before the war, nicknamed the "pineapple" for its grooved surface. This weapon was widely used by American G.I.s. The heavy, segmented bodies of "pineapple" type grenades produce 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 replaced by the L2 series.^{[citation needed]}

Explosive grenades

Fragmentation

When the word grenade is used without specification, and context does not suggest otherwise, it is generally assumed to refer to a fragmentation grenade.^{[citation needed]}

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) against an open area outside, and have an effective kill radius greater than the distance they can be thrown; while the latter are for use by assaulting troops, and have a smaller effective radius.^{[citation needed]}

The Mills bombs and the French/Soviet F1 are examples of defensive grenades. The Dutch V40, Swiss HG 85, and US MK3 are examples of offensive grenades.^{[citation needed]}

High explosive (offensive)

The high explosive (HE) or concussion grenade is an anti-personnel device that is designed to damage, daze or otherwise stun its targets with overpressure shockwaves. 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).^{[citation needed]}

Some concussion grenades with cylindrical bodies can be converted into fragmentation grenades by coupling with a separate factory-made payload of fragments wrapped around the outside: a "fragmentation sleeve (jacket)", as shown in the WW2 Splitterring sleeves for the stick grenade and M39 "egg hand grenade".^{[citation needed]}

Anti-tank

A range of hand-thrown grenades have been designed for use against heavy armored vehicles. An early and unreliable example was the British sticky bomb of 1940, which was too short-ranged to use effectively. Designs such as the German Panzerwurfmine (L) and the Soviet RPG-43, RPG-40, RPG-6 and RKG-3 series of grenades used a high-explosive anti-tank (HEAT) warhead using a cone-shaped cavity on one end and some method to stabilize flight and increase the probability of right angle impact for the shaped charge's metal stream to effectively penetrate the tank armor.^{[citation needed]}

Stun

Main article: Stun grenade

A stun grenade, also known as a flash grenade or 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 a distraction grenade.^{[citation needed]}

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.^{[citation needed]}

These grenades are designed to temporarily neutralize the combat effectiveness of enemies by disorienting their senses.^{[citation needed]}

When detonated, the fuze-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 generally cause fragmentation 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 g (0.16 oz) of a pyrotechnic metal-oxidant mix of magnesium or aluminium and an oxidizer such as ammonium perchlorate or potassium perchlorate.^{[citation needed]}

Chemical and gas

Smoke grenades are used as ground-to-ground or ground-to-air signaling devices, target or landing zone marking devices, and to create a smoke-screen for concealment. 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. There are two main types, one producing coloured smoke for signaling, and the other is used for screening smoke. In coloured smoke grenades, the filler consists of 250 to 350 g (8.8 to 12.3 oz) of coloured smoke mixture (mostly potassium chlorate, lactose and a dye). Screening smoke grenades usually contain HC (hexachloroethane/zinc) or TA (terephthalic acid) smoke mixture and white phosphorus (WP) and red phosphorus (RP). HC smoke contains hydrochloric acid and is harmful to breathe. These grenades can become hot enough to scald or burn unprotected skin, particularly the phosphorus type grenades.^{[citation needed]}

Tear gas grenades are similar to smoke grenades in shape and operation. In tear gas grenades, the filler is generally 80 to 120 g (2.8 to 4.2 oz) 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. Occasionally CR gas is used instead of CS.

Incendiary grenades produce intense heat by means of a chemical reaction. Seventh-century "Greek fire" first used by the Byzantine Empire, which could be lit and thrown in breakable pottery, could be considered the earliest form of incendiary grenade.^{[citation needed]}

The body of modern incendiary grenades is often similar in appearance to that of a smoke grenade, though generally smaller in size. The filler can be various chemicals, and while white phosphorus is well known, red phosphorus is also used for a number of reasons, not least because it is more stable and requires ignition, making it a safer option for the troops using it. White phosphorus was used in the British No. 77 Mk. 1 and in a solution form for the British Home Guard's No 76 special incendiary grenade during World War II.^{[citation needed]}

The Molotov cocktail is an improvised incendiary grenade made with a glass bottle typically filled with gasoline (petrol), although sometimes another flammable liquid or mixture is used. The Molotov cocktail is ignited by a burning strip of cloth or a rag stuffed in the bottle's orifice when it shatters against its target which sets a small area on fire. The Molotov cocktail received its name during the Soviet invasion of Finland in 1939 (the Winter War) by Finnish troops after the former Soviet foreign minister Vyacheslav Molotov, whom they deemed responsible for the war. A similar weapon was used earlier in the decade by Franco's troops during the Spanish Civil War.^{[citation needed]}

Design

Various fuzes (detonation mechanisms) are used, depending on purpose:

Impact

Examples of grenades fitted with contact fuzes are the German M1913 and M1915 Diskushandgranate, and British grenades fitted with the No. 247 "All ways" fuze - these were the No. 69 grenade, No. 70 grenade, No. 73 grenade, No. 77 grenade, No.79 grenade and No. 82 grenade (Gammon bomb).^{[citation needed]}

Instantaneous fuze

These have no delay and were mainly used for victim actuated booby traps: they can be pull, pressure or release switches. Booby traps are classed as mines under the Ottawa Treaty.^{[citation needed]}

Timed fuze

In a timed fuze grenade, the fuze is ignited on the release of the safety lever, or by pulling the igniter cord in the case of many stick grenades, and detonation occurs following a timed delay. Timed fuze grenades are generally preferred to hand-thrown percussion grenades because their fusing mechanisms are safer and more robust than those used in percussion grenades. Fuzes are commonly fixed, though the Russian UZRGM (Russian: УЗРГМ) fuzes are interchangeable and allow the delay to be varied, or replaced by a zero-delay pull fuze. This is potentially dangerous due to the risk of confusion by operators.^{[citation needed]}

Beyond the basic "pin-and-lever" mechanism, many contemporary grenades have other safety features. The main ones are the safety clip and a locking end to the release pin. The clip was introduced in the M61 grenade (1960s, Vietnam War), and was also then known as the "jungle clip" – it provides a backup for the safety pin, in case it is dislodged, eg. by jungle flora. This is particularly important as poorly trained troops have been known to use the safety lever as a hook from which to suspend the grenade, despite the apparently obvious danger this poses. The 2016 US ET-MP uses a user-settable timed electronic fuze, though neither the fuze nor grenade have yet been accepted into service anywhere in the world.^{[citation needed]}

Use

The classic hand grenade design has a safety handle or lever (known in the US forces as a 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 an explosion. Some grenade types also have a safety clip to prevent the handle from coming off in transit.^{[citation needed]}

To use a grenade, the soldier grips it with the throwing hand, ensuring that the thumb holds the safety lever in place; if there is a safety clip, it is removed prior to use. Left-handed soldiers 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. They then throw the grenade towards the target. Soldiers are trained to throw grenades in standing, prone-to-standing, kneeling, prone-to-kneeling, and alternative 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.^{[citation needed]}

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 fuze (sometimes called the delay element). The fuze burns down to the detonator, which explodes the main charge.^{[citation needed]}

Within this range, people are generally injured badly enough to effectively render them harmless. 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 m (750 ft) away.^{[citation needed]}

This technique is inherently dangerous, due to shorter delay (meaning a closer explosion), greater complexity (must make sure to throw after waiting), and increased variability (fuzes vary from grenade to grenade), and thus is discouraged in the U.S. Marine Corps, and banned in training.^{[citation needed]} Nonetheless, cooking a grenade and throwing one back is frequently seen in Hollywood films and video games.^{[citation needed]}

Tactical applications

Tactics vary by the type of engagement. Urban warfare, particularly the attack of built-up (fortified, buildings etc.) areas, involves the heavy use of hand grenades: typically a grenade or two are thrown before each transition (entering a room or navigating a stairway).^{[citation needed]} A World War II battalion fighting in a city frequently used 500 grenades per day.^{[citation needed]}

A key concern is that the grenade is picked up and thrown away or back at the thrower. The USMC's 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 as to reach upper floors of a building, a grenade may be lobbed for greater distance or accuracy.^{[citation needed]}

Throwing a grenade upstairs is dangerous, due to the risk of it falling back down; it is much safer to throw a grenade downstairs, so it is safer to capture a building from the top, rather than the bottom.^{[citation needed]} Grenades generally explode near the floor, causing spalling downwards towards lower floors.^{[citation needed]}

The preferred technique in the US forces when attacking is to show the grenade to nearby friendly forces, receiving a visual acknowledgment, to avoid alerting the enemy. Alternatively, a voice alert can be given immediately after throwing the grenade, shouting "frag out"^{[citation needed]} (for "fragmentation grenade outgoing"); this reduces or eliminates the element of surprise. Conversely, on identifying an incoming enemy grenade, friendly forces shout "grenade".^{[citation needed]}

Booby traps

Grenades have often been 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.^{[citation needed]}

Abandoned booby traps and discarded grenades contribute to the problem of unexploded ordnance (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.^{[citation needed]}

Cultural impact

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.^{[citation needed]}

The branch insignia of the United States 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 marine gunners replace the rank insignia worn on the left collar with a "bursting bomb" and a larger "bursting bomb" insignia is worn 3⁄4 inch (2 cm) 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.^{[citation needed]}

Legislation

In the United States grenades are classed as destructive devices, a form of Title II weapons under the National Firearms Act. They must consequently be registered with the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF), are taxed, and are illegal in states that ban Title II weapons. While in principle it is possible to legally obtain and possess hand grenades in some states, in practice they are not generally available.^{[citation needed]}