The violent explosion of a grenade creates smoke and dust, with a modest flash in daylight; at night a more significant flash may dazzle those nearby. Most grenades cause casualties (dead and wounded) by blast and fragmentation. Blast can cause severe injuries. It is much reduced in the open, but within enclosures blast is greatly magnified. Blast can be reflected from hard surfaces and is more pronounced in such circumstances than in a muddy field. Injuries resulting from blast overpressure include concussion and shock, while explosive flash can result in lacerations, dismemberment, internal injuries, eye and ear damage, and burns.
Fragmentation is the real casualty producer, however. When detonated, a grenade’s body produces dozens to hundreds of fragments – AKA splinters or shrapnel. (The latter term is technically incorrect, but commonly used. Invented by a Royal Artillery officer, Henry Shrapnel, in 1784, shrapnel was an artillery projectile filled with a bursting charge and lead balls (shrapnel); it was designed to burst in the air to shower troops from above.) The more fragments produced the greater the number of casualties, and casualties are more severe owing to multiple wounds. Fragment size is important – too small and they may inflict only minor wounds. Explosives with an extremely high brisance can shatter the grenade’s body to such an extent that some fragments will be no larger than grains of sand. Small fragments may not have sufficient mass and velocity (3,000ft/sec and greater) to pierce thick clothing or penetrate a human body deeply enough to damage organs. Large fragments can travel too far, however, and endanger exposed friendly troops. Fragments weighing at least 0.15g (2.3 grains) and measuring at least 3mm (0.12in) in diameter are considered the minimum to inflict incapacitating wounds. Multiple wounds from small fragments are generally necessary to incapacitate the target. As an example, the US M26/British L2 frag has a fragmentation pattern of 3.7 fragments per square meter (1.2sq yd) at 5m (5.47yd) and only 0.9 fragments per square meter at 10m (10.94yd). The fragments struck with an energy of about 86J (63.43ft lb) at 5m – sufficient force to penetrate thick clothing and deeply enough into the body to damage organs.
US Marines, sheltered by a purpose-built concrete grenade-throwing pit, are pictured during training in the M67 grenade at Camp Lemonnier, Djibouti, in January 2008. Note the mid-air separation of the safety spoon from the rest of the grenade. Grenade explosions are not the massive, gasoline-enhanced fireballs often depicted in movies. Also, in contrast to Hollywood portrayals, a single grenade will seldom blow off a tank tread, lift a car off the road, disintegrate a building, or blast gaps through barbed wire. (US Navy)
Casualty radius is subject to much variance. The criteria for determining the number of casualties produced within a given radius varies by country and errs on the high side. Casualty radius is usually defined as a radius from the point of detonation in which at least 50 percent of standing personnel are killed or incapacitated. At least a quarter of a grenade’s fragments are absorbed into the ground and others go straight up. Deep mud or snow can “smother” some of a grenade’s effects. Dense vegetation can “dampen” blast and fragmentation. Of course, when it is stated that a grenade’s casualty radius is 5m (5.47yd), that does not mean there were no casualties outside of that. A grenade bursting over the heads of troops would cause more casualties in a wider radius than on the ground. Results in the field usually do not replicate test-center statistics. Secondary fragmentation (gravel, rocks, masonry, wood splinters, glass, etc.) propelled by the blast also causes injuries.
Fragmentation and blast effects are not consistent in a 360-degree radius. Most grenades were oval- or can-shaped and fragmentation generated from the ends was less than from the sides, resulting in uneven patterns. Two extreme examples are found in Stephen Ambrose’s Band of Brothers describing the effects of German Stg 24 stick grenades. The first event occurred in Normandy:
A German potato masher sailed into the trench; everyone dived to the ground. “Joe, look out!” Winters called to Toye. The grenade had landed between his legs as he lay face down. Toye flipped over. The potato masher hit his rifle and tore up the stock as it exploded, but he was uninjured. “If it wasn’t for Winters,” Toye said in 1990, “I’d be singing high soprano today.” (Ambrose 2002: 97–98)
The second event took place in the Netherlands: “Other Germans pitched grenades of their own over the dyke. Alley got blown to the ground by a blast of shrapnel that left thirty-two wounds in his left side, face, neck, and arm” (Ambrose 2002: 189).
It is extremely difficult to make a meaningful comparison between grenades and other types of weapon in terms of their ability to inflict casualties. Grenades are essentially HE-delivering “micro weapons,” that is, while destructive to point targets, they are not widely destructive like artillery and mortar barrages. In World War I, the British Army recorded that 2.19 percent of its casualties were caused by grenades as opposed to 58.51 percent caused by shells and mortar bombs. In the equivalent statistics for World War II, grenades were included in a much larger category also covering mortar bombs, aerial bombs, and artillery shells; 75 percent of casualties were attributed to this larger category, with a further 15 percent being attributed to blast, crush, phosphorus and other miscellaneous causes (Holmes 2004: 210). During World War II the US Army suffered 0.5 percent dead and 2.5 percent wounded to grenades. A further 0.2 percent were killed and 0.5 percent wounded by booby traps, many of which were made from grenades. The ratio is small when compared to over 50 percent killed by artillery and over 30 percent by small arms. Determining the numbers of casualties caused by grenades is difficult owing to poor record-keeping in the field and recording wounds only as “fragmentation” (which could be caused by many munitions). Casualties listed as caused by “booby traps” may have been from grenades too. In Vietnam the United States lost 4,100 men to grenades and mines. Additionally, almost 7,400 were lost to “multiple fragmentation wounds,” which no doubt included grenades. To the infantryman in the line, however, grenades provided an invaluable extra dimension to the damage he could inflict in the immediate combat range of action that concerns the soldier – approximately 50yd – much more so than the rifle and bayonet.
Before deploying to South Korea, US Marines practice building clearing with a practice grenade in a mock Korean village at California’s Camp Pendleton in 1953. The reality is that an actual detonating fragmentation grenade would kill or wound all three men owing to large fragments penetrating the light wooden wall. Structures with thin wooden or thatch walls will not stop grenade fragments. Clearing a room by tossing in a grenade and sheltering outside behind thin walls results in friendly casualties. The use of blast (offensive) grenades reduces this possibility. While all armies, until recent years, have taught soldiers to fire shoulder weapons right-handed regardless of their dominating arm, it was recognized that forcing a left-handed soldier to throw right-handed was ineffective and dangerous. Left-handed throwers typically grip a grenade upside-down so the arming pin is on the opposite side of the fuse as it would be when held right-handed, allowing it to be pulled with the opposing (right) hand. (Tom Laemlein/Armor Plate Press)
For troops in the attack the best defense against grenades is to keep moving and avoid being pinned down within grenade range. Of course, enemy fire and obstacles can hamper a unit’s movements. If receiving grenade barrages and other enemy fire and obstacles permit, the attacking unit should move out of the area. Grenade battles – what the Germans called a Schneeballschlacht (snowball fight) – should be avoided. If in the open and grenades land nearby, troops should hug the ground with the helmet toward the grenade and protect the face with the arms.
World War I-era German grenadiers practice throwing stick grenades steep and high to overcome a barrier. Note the practice grenades hung in the wire mesh thrown at them by other practicing grenadiers. They practice throwing with their rifles slung, as they would be in combat. This type of barrier was erected in front of trenches prone to enemy trench raids and grenade attacks. (Tom Laemlein/Armor Plate Press)
There are more options in the defense, time and materials permitting. The parapet of a foxhole or trench may prevent grenades from being tumbled into the position. The parados protects soldiers firing forward if grenades land behind the position. During World War I the front edge of trenches were squared rather than sloped to help deflect grenades. The Germans learned to dig narrow trenches, making them harder to grenade. Wire mesh could be erected in front of vulnerable trench sections and sloped inward. This mesh had to be high enough that a grenade thrown over it would land behind the trench. Exposed trench sections with a probability of being captured had a 1ft mesh of wire over them; if captured, the mesh could be bombed out as it did not deflect grenades, but prevented occupiers from throwing grenades.
Mesh can be placed over firing ports or windows to deflect grenades. This of course could be shot out by an automatic weapon, but it will protect from grenades during the initial assault. If a firing port is at ground level, a small pit can be dug in front of it to catch rolling grenades and prevent debris from artillery from blocking the port. Mesh, bed frames, mattresses, or boards can block windows. Building defenders expecting attackers to grenade rooms can erect a hasty “corner barricade” in a corner out of sight from the door. This would be built of furniture and mattresses – anything to stop fragments. Once the grenade detonated the defenders would fire on anyone entering the room from the door’s blind side. During World War II US and Japanese troops sometimes dug grenade sumps in foxhole and pillbox bottoms into which grenades could be kicked.
During World War I bombing posts were prepared behind forward trenches from which grenadiers could bomb out the captured trench. Bombing posts were also prepared to cover sections of front-line trench to block attackers moving down the trenches. Sandbags and timbers were stockpiled to build barricades. The final protective wire – a barbed-wire barrier closest to the defensive position – is typically just outside of grenade range of the positions to prevent the attackers from ranging them – 20–40m (22–44yd) – considering the enemy will be most likely throwing from the prone. Of course the enemy outside the wire will be beyond the defenders’ grenade range. Instead, this is covered by grenade launchers and machine-gun and mortar final protective fires, plus booby-trapped grenades in the wire. Close-in dead spaces that cannot be covered by direct-fire weapons, approaches such as gullies and ditches, and dense concealing vegetation can be designated target areas and individuals assigned to grenade them. Grenades can be thrown short of the wire if the enemy begins crossing it.
At a 3rd Armored Division armored rifle company’s ammunition distribution point, Mk IIA1 fragmentation grenades are ready for issue. Some have been packed in an M1932 musette bag. Among the frags is an M15 WP grenade. (Tom Laemlein/Armor Plate Press)
A reality of grenades is the fact that the delay – typically 4–5 seconds – allows a quick and agile enemy to throw back a grenade, what the Germans called a leih-Ei (loaned egg). Clearly, this is risky as it is not known how much time remains. Of course, if the enemy combatant is unable to immediately exit the structure or foxhole when a grenade enters, there is little choice. Individuals attempting to return a grenade have lost hands, arms, and lives. Others have thrown themselves on grenades to protect comrades. Some even survive, although horribly wounded. Body armor, helmets, or even a rucksack have saved soldiers. This has occurred both in combat and in training accidents. In US service the Medal of Honor is awarded, while Britain presents either the Victoria Cross (posthumously) or George Cross (survived) and France the Croix de guerre. Soviet (and then Russian) soldiers are honored as a Hero of the Soviet Union (or Russian Federation); Israel awards the Medal of Courage, its second-highest valor medal, to those in combat, or the Medal of Distinguished Service to those involved in a training accident. Until 1945 Germany granted the Iron Cross, its grade depending on what earlier grades the recipient had received. During World War II, Japan had no such consideration for those sacrificing themselves for comrades. They sacrificed themselves for the Emperor, considered to be an honor in itself.
Extra precautions are necessary with dud grenades – “blinds” in British parlance, and Blindgänger in German – also termed a Eunuch, Leisetreter (“pussyfoot”), or zahmer Tommy (“Tamer Tommy” – a dud explosive munition). Typically, duds are caused by the primer or detonator failing, or the delay fuse failing to ignite. Percussion grenades with a firing pin may have jammed the pin and if disturbed might activate. Dud delay-fused grenades are especially dangerous. No dud grenade should ever be moved. If possible they should be marked and engineers or explosive ordnance disposal personnel will take care of them, usually with demolition charges – this is known as being “blown in place.”
Especially in the early days of mass-produced grenades, inherent design flaws could make such weapons very dangerous to the user. One German infantry officer who fought on the Somme, Landwehr-Leutnant M. Gerster, recalled the steady improvement in the variety and quality of hand grenades during 1915:
The makeshift hand grenades available on the outbreak of war disappeared gradually. Factory-made types replaced them: the discus grenade, which gradually disappeared too; the ball-shaped grenade, later relieved by the lighter egg grenade, which could be thrown further and the stick grenade. The safety device of the stick grenade was a constant source of concern and anger for the company commanders. Despite all care, again and again the firing cord was accidentally caught and pulled on exiting dugouts, or when passing along trenches revetted with wooden hurdles. This ignited the grenade without the carrier being aware of the fact, thus putting him in mortal danger. The star screw catch, which was introduced after much experimentation, finally produced a splendid solution to a problem which was far from insignificant for the infantry. (Quoted in Sheldon 2007: 79)
Although some subsequent commentators have rated the World War I-era German stick and egg grenades more highly than the Mills Bomb in terms of throwing range, at the time both sides appear to have viewed the British grenade to be the superior weapon – not least owing to its lethal fragmentation effect. The Germans found they were hampered by the sheer length and size of the stick grenade, and by the lack of throwing skills among new recruits. In October 1916 one German officer reported that his men consisted “almost two-thirds of replacements, who had no acquaintance with hand grenades, and therefore did not stand a chance against the British, who are very well trained in this respect. Our few good grenade-throwers had been reassigned almost immediately, and we received nobody to take their place” (quoted in Duffy 2007: 281).
During the early days of mass-produced, mass-issue grenades, new types could arrive at the front too late to see widespread service. After a campaign that saw the widespread use of improvised grenades by both sides, the Allied evacuation of the foothold at Gallipoli in 1915–16 coincided with Mills Bombs finally appearing at the front:
… the officers took a last look along the line. A lieutenant … heard the sound of bombs exploding. He found a lone Australian trying out the new Mills bomb grenades, which had only just arrived and were rationed because they cost the fabulous sum of 17 shillings and sixpence each. “It’s a pity not to use them,” the lone bomber explained, “they’re great.” (Quoted in Carlyon 2003: 634)
Untold millions of grenades have been expended in combat since World War I. Grenades were in constant demand. Units in the defense stockpiled grenades in forward positions, be they foxholes or defended buildings, and reserve stocks were held at each echelon: company, battalion, and regiment/brigade. Grenades would be stockpiled in fallback positions as well. Units in the attack typically required each man to carry 2–4 grenades; more were carried in bulk by reserve units, often in boxes, buckets, or sandbags. Resupply carrying parties also brought additional grenades forward. Such practices could make the carrier particularly vulnerable to enemy fire, as one German machine-gun officer, Reserve-Leutnant Borelli, recalled of his service on the Somme in July 1916:
My machine gun crews suffered heavy casualties because the British, who were sheltering in the craters directly to our front, could not be brought under fire and so were able to throw grenades with impunity … Our shortages of grenades and flares made themselves felt and it was not until dawn that we could see the individual groups of British troops lying on the ground and seeking cover in the shell craters … It seemed that the British carried large stocks of grenades on their waist belts because we saw that often our bullets were causing explosions. (Quoted in Sheldon 2007: 193–94)
The US Army issued the three-pocket grenade carrier from late 1944. The carriers were safer, protected the arming pin from accidentally being snagged, provided mud and weather protection, made grenades easily accessible, and negated the need to tape pull rings or levers. These carriers were also used in Korea. The US Marine Corps issued a similar two-pocket carrier. (Tom Laemlein/Armor Plate Press)
Amid such shortages it was routine for troops to use captured grenades against their former owners. If not formally trained to use enemy grenades, units in combat quickly had to learn how to employ them safely. Even where grenades were available, hastily trained troops found them dangerous to use, as the Soviets found during the battle for Stalingrad in 1942–43:
Not surprisingly, there were many accidents caused by untrained soldiers. The second-in-command of a company was killed and several men were badly wounded when a newly arrived recruit mishandled a grenade. Others were killed when soldiers, mainly from Central Asia, tried to fit captured German detonators in their own grenades. “Further weapon training is needed,” the chief of the political department reported to the military council of Stalingrad Front. (Quoted in Beevor 1999: 153)
Hand-grenade throwing range is limited by physical properties. Weight is of course a factor, but unlike other weapons’ capabilities – affected by propellant, projectile design, barrel length, etc. – the range of grenades is limited mostly by the thrower’s strength, agility, proficiency in throwing techniques, and even the clothing and equipment he wears. Grenades are close-range weapons and the average 30–40m (33–44yd) range was seen as sufficient in most cases. A strong and proficient thrower using a lighter grenade might achieve 50m (55yd). There are of course always circumstances in which more range is desired. This led to rifle grenades being developed at the turn of the century, at the same time hand grenades were recognized as still of value.
The first type of rifle grenade involved a cup discharger being fitted to a rifle’s muzzle. The grenade, often a modified hand grenade, was inserted in the cup and launched using bulletless cartridges with a special propellant charge. It is important to note that grenade-launcher cartridges were not technically “blank” cartridges as so often reported. Some countries used launcher cartridges with solid or hollow soft-wood bullets that shattered when fired. These were not substitutes for metallic bullets intended to be fired at personnel as is sometimes rumored. Another type was the spigot launcher, involving a tube being attached to the rifle’s muzzle and the use of grenades fitted with a tailboom. The tailboom, which included stabilizing fins, was slid onto the launcher tube. This allowed the range to be adjusted, up to a point. The farther down the tube the tailboom was slid, the longer the range. Rifle grenades could be fired horizontally to provide direct fire, or indirectly, with the rifle’s butt planted on the ground and angled upward. Some were provided with special sights to set the elevation, but often this was simply estimated. They were not generally accurate weapons. Their range was typically 75–150m (82–165yd) for indirect fire. For direct fire, used against armored vehicles, pillboxes, or crew-served weapons positions, they were seldom effective beyond 100m (110yd).
Three äusserst Feldgrau (“extremely field gray,” i.e., very experienced) front-line German soldiers on the Eastern Front show two of the commonest means of carrying hand grenades. An Stg 24 stick grenade is stuck in the belt of the left man and an Eihgr 39 egg grenade is suspended by a carrying ring on its bottom fastened to a cartridge pouch’s securing strap on the right man. Stick grenades in the belt were easily accessible for throwing, but made it difficult to run at a low crouch or during a low crawl. Also, grenades were easily lost when crawling, and the fuses could be jammed with mud, dirt, snow, or vegetation debris. (Courtesy of Concord Publications)
Rifle grenades supplemented hand grenades, filled the range gap between hand grenades and light (50–60mm) mortars at company level, and also, at the beginning of World War II, served as barely adequate AT weapons. In the opening years of that conflict, the first munitions developed by most armies bearing the new AT shaped charge were rifle grenades. These soon became obsolescent against tanks, but were still effective against light armor and hardened structures. Rifle grenades also included antipersonnel (HE/frag), screening and marking smoke, illumination, signal flares, and tear gas models. Many countries developed grenade projectors – light, simple mortars – on the eve of World War II to replace or supplement rifle grenade launchers at platoon level. Some could provide direct fire, not just indirect fire. Although a few countries retained weapons of this type in the post-war years, they mostly fell from use by the end of World War II as their small projectiles were insufficiently potent – not much more powerful than a hand grenade – and were too heavy and short-ranged. Rifle grenades, too, were largely phased out by the 1970s, being replaced by under-barrel 40mm grenade launchers (UGL) as well as by single-shot, throwaway, shoulder-fired AT rocket launchers. The 40mm UGL was pioneered by the United States, with the M79 and M203 developed during the 1960s eventually leading other countries to produce them.
There are few truly new types of grenades. HE/fragmentation grenades remain the mostly widely used type, being true multipurpose weapons. Pure blast grenades – that is, grenades with thin, light, limited fragmenting bodies – have all but fallen from use. Many modern HE/fragmentation grenades have smooth bodies of thin materials, even plastic bodies, and it is often assumed that since they lack “fragmentation” segmentations that they are blast grenades when in fact they contain efficient fragmentation liners. The idea of impact-detonated grenade fuses occasionally reemerges, but as before, they are largely rejected by the troops owing to their inherent dangers.
Colored smoke grenades are still very much in use. Hazardous pyrotechnic mixtures, especially zinc and sulfur, are being replaced by safer materials, and denser, more vivid, and longer-duration smoke compounds are under development. With all the turmoil found in the world since World War II, it is no wonder that riot-control or tear-gas grenades have come into wide use. Usually can-shaped, such grenades contain densely packed CS powder, virtually the worldwide standard for tear gas. They are not limited to only the armed forces, being used by law-enforcement and internal-security forces as well. Burning tear-gas grenades become extremely hot, making it hazardous for protesters to pick them up and throw them back. Riot-control grenades used by law-enforcement agencies are developed and produced by commercial enterprises and can be quite innovative. One example is the US Federal Laboratories Model 515 triple-chaser tear-gas grenade. After impacting it breaks into three sections, with each bouncing in different directions to skitter about; this makes them almost impossible to throw back and spreads CS over a larger area. The same firm also produces a burning type CS grenade that additionally generates dense white smoke to further confuse and disorientate rioters. Extremely dense burning-type smoke grenades are also available to blind rioters. Another type of riot-control grenade is the bursting type. These are spherical grenades with frangible plastic bodies, thrown to airburst over the heads of rioters and quickly saturate a large crowd. An example of this type is the US M25A2 with a baseball-sized bursting frangible body. Another is the softball-sized XM47E3 with a rubber body. It is rubber so that when thrown into a crowd it is less likely to injure a person. They spew CS through a small port and spin the grenade erratically on the ground.
As with all armies the Germans found grenade expenditure to be much heavier than anticipated during World War II. Their own production could not keep up and they readily made use of captured and impounded grenades. Here an Obergrenadier, an assistant squad leader of a rifle squad (Schützengruppe), collects the day’s allotment of German- and Soviet-made grenades from the company ammunition supply point (Munitionsausgabestelle), dealt out by the Feuerwerker (armorer NCO), an Unterfeldwebel. The Obergrenadier wears the carrying pouches for rifle grenades (Tragetaschen für Gewehrgranaten). Each of the two bags held four stick grenades or several rifle grenades or other types of grenades. They were also locally made using a pair of sandbags with scrap webbing and rope. Stick grenades were also carried on the person in jackboot tops, belt, tunic front, or strapped to entrenching-tool carriers. In the foreground feet is a cluster charge (Geballte Ladung) made up of six Soviet RG-42 grenades with the fuses removed and wired around a Stg 24 stick grenade. Although this arrangement was meant to employ stick-grenade heads with the handles removed, it was common to use captured grenades instead. The cluster charge was intended to be thrown into tank treads or pillbox firing-ports for considerable blast and fragmentation. Similarly, two stick or egg grenades could be wired or taped together, one ignited, and thrown into rooms or pillboxes to provide more devastating blast and fragmentation effects – as a double grenade (Doppel-Granate) or doorknocker (Türklopfer) – not shown. The Feuerwerker divided up the daily allowance of grenades allotted by battalion and then divided them up between the company’s nine squads – leading him to be called the Waffengott (“weapons god”). Today’s allotment is comprised of: Stg 24 stick grenades (five fragmentation sleeves were issued in each case); a few of the Nb Hgr 39, appearing similar to the Stg 24, but with a white band, and burning for 100–120 seconds; some Eihgr 39 nA grenades, temporarily suspended by their rings from the securing straps of the Obergrenadier’s cartridge pouches; and a couple of Soviet RGD-33 Dyakonov hand grenades with fragmentation sleeves. Also issued is a carton of four Blendkörper 2H (“blinding smoke pots 2H”), one of which he is examining. It released dense white smoke when shattered against a tank and the titanium tetrachloride (FM) filler came into contact with air. It generated smoke for 15–20 seconds; intended to blind tank crews, the strong acidic smoke could be drawn into the tank to drive out the crew. Both steel and wooden grenade containers were to be returned through the supply system for reuse.
The most recent addition to the irritant chemical grenade family is an Indian-made crowd-control grenade introduced in 2010. It is packed with finely ground seeds of the bhut jolokia chili pepper (AKA ghost pepper), declared by the Guinness Book of World Records to be the hottest pepper in the world. The weaponized bhut jolokia measures 855,000–1,050,000 units on the Scoville scale, twice as hot as the next fieriest pepper, the Mexican red savina habanero pepper at 350,000–1,050,000. When the grenade bursts it spreads a non-toxic mist that burns the eyes, nostrils, and mouth so severely it causes temporary blindness, airway irritation, and breathing difficulties. The idea came from the pepper’s longtime use to ward off rogue elephants. Peppers were burned in fires and the vapor drifted in the smoke – downwind from the elephant-harassed village.
Stun or flash-bang grenades are mainly employed for counterterrorist operations, especially when hostages are involved. Police also use them in hostage situations and they can be used for riot control. They should not be used around children or the elderly, but in dire situations they might have to be resorted to. They also have application in military operations, again, especially where civilians are involved such as during urban combat. The use of stun, burning-type riot control, and smoke grenades in violent civil disturbances, must be employed with caution. They can ignite flammable materials, create panic among rioters – causing a confused situation to get completely out of control – and affect the elderly, children, and those with respiratory problems. Smoke and tear gas displaces oxygen in confined enclosures and can lead to suffocation.
A newer type of riot-control grenade is the sting grenade, such as the US commercially produced Combined Tactical Systems Model 9590 sting-ball grenade. This is a spherical, rubber-bodied grenade containing 105 .31-cal hard plastic balls. The grenade airbursts, showering the pellets on the crowd and separating the fuse assembly from the body. After a brief delay, the fuse body detonates with a brilliant and loud flash-bang charge. They can also contain tear-gas powder mixed with the plastic pellets. The pellets are quite painful, even when wearing medium-weight clothing.
Adopted in 1995, the US M84 stun grenade creates an extremely loud 170–180dB at 5ft, louder than a shotgun muzzle blast or space shuttle launch (an ambulance siren or jet engine is 120dB and a rock concert is 100dB and up). Noise pain threshold is 120dB and permanent ear damage is caused at 140dB collected simultaneously with a 6–8 million candela flash. Double-hearing protection – insert-type hearing protectors plus earmuff-type hearing protectors – is recommended for friendly personnel in the vicinity. The M84 is reported to effectively stun and disorientate individuals within 5–9m (5–10yd). The M84 weighs 8.33oz, is 5.25in high, and 1.73in in diameter. The M201A1 fuse has a delay of 1–2.3 seconds. The 0.16oz charge is a magnesium/ammonium nitrate pyrotechnic mixture. While its shape is unique, the M84 is identified by OD body (early ones had a back body) with a light-green band. It has double arming rings for surer safety; the circular one is pulled first, then the triangular. (Public Domain)