Grenade

-A Reading from the Book of Armaments, Chapter 4, Verses 16 to 20:

'Saint Attila raised the Hand-Grenade up on high saying, "O' Lord, bless this thy Hand-Grenade that with it thou mayst blow thy enemies to tiny bits. In thy mercy." And the people did rejoice and did feast upon the lambs and toads and tree-sloths and fruit-bats and orangutans and breakfast cereals … Now did the Lord say, "First thou pullest the Holy Pin. Then thou must count to three. Three shall be the number of the counting and the number of the counting shall be three. Four shalt thou not count, neither shalt thou count two, excepting that thou then proceedeth to three. Five is right out. Once the number three, being the number of the counting, be reached, then lobbest thou the Holy Hand Grenade in the direction of thine foe, who, being naughty in my sight, shall snuff it."'

— "Monty Python", Monty Python and the Holy Grail

Basic Information

"Hand-flung bomb" is not Chinese for grenade!

Etymology & History

Whatever the Chinese may be for it¹ a grenade is, more or less, a hand flung bomb. That is, it is an explosive device designed to be thrown by hand - there are also rifle grenades and grenade launchers, but those tend to use something a little different. Strictly, the "manual version" can be called a hand grenade, but since these are the default type (for the time being) the "hand" is usually assumed.

The name comes from the word for pomegranate - due to the resemblance of early models to the fruit in question - and they seem to appear first in the Eastern Roman Empire in the 8th Century AD. Ironically they contained Greek Fire or naptha at that point and were glass or ceramic shelled - more like molotov cocktails than a modern grenade.

For an explosive filler we need to look to the Chinese, who seem to have had primitive black powder grenades on issue by the 11th century, possible inspired by the Byzantine devices which by then had been copied by their mutual neighbours the Baghdad Caliphate.

Explosive grenades seem to appear in Europe around the 17th Century - the classic "flaming onion" design of a cast iron sphere with a burning fuse poked into the top. Most nations developed hand picked corps of "Grenadiers" to use these weapons … and then, in general, used such elites for other duties, reflecting the fact that the grenades of the time were not much help outside a few limited contexts². The grenade then pops up from time to time, frequently improvised by cunning infantrymen, appearing in the War Between the States, the Crimean War and the Russo-Japanese Wars, until WW1 where the development of trench warfare made the grenade suddenly very useful.

Two main types were developed - the stick grenade, or "potato masher", (consisting of a charge on a long wooden handle for easy throwing), which was mainly used by the Central Powers and the egg grenade (sort of egg shaped) mainly used by the Entente. These were used fairly promiscuously and remained pretty much unchanged into WW2³, after which the stick grenade finally died out, leaving egg types in control of the market.

The Modern Grenade

Modern grenades are perhaps best divided into explosive vs. everything else.

Explosive grenades further divide into offensive and defensive grenades - the former being lighter and generally soft-cased, making them easier to throw further so that advancing troops can throw them ahead of themselves without too much risk of fragments flying back at them. Defensive grenades, by contrast, are designed to be thrown from hardened positions and so are heavier and contain more fragment producing material⁴ in the casing. Some modern designs - termed offensive/defensive grenades have a removable sheath of fragmenting material around an offensive design of grenade. Remove the sheath and you have a usable offensive grenade, keep it on and you have a deadly defensive weapon.

By rule of thumb, explosive grenades can be expected to kill at about 5m from point of detonation and reliably wound out to 15m, but this can vary both in terms of offensive/defensive role and around things like the surface it detonates on. See Inverse-Square Law for some insight into the math behind the radius at which it does damage. Older designs tended to have a larger fragment radius - sometimes more than the distance that they could be thrown by an average soldier. This also tended to be a problem with early white phosphorous grenades (see below).

"Everything else" would normally include the following:

• Chemical Agent (normally CS or similar … not much point to anything else)
• Smoke (white, coloured or white phosphorous)
• Incendiary (white phosphorous, red phosphorous or thermite/thermate)
• Stun (aka. "Flashbang" - designed to stun with bright light and loud noise)
• Stingball (a less lethal weapon that fires a spray of rubber balls - and often CS)
• Paint (mainly a toy, but used for marking work in crowd control)
• Anti-armour (largely obsolete, uses a shaped charge to penetrate vehicle armour)

A grenade will be detonated by one (or both) of two methods:

1. Time delay: the operator starts a timer (usually a chemical fuse) which, after a set delay, fires the charge.
2. Impact: the operator arms an impact sensor which fires the charge when the grenade strikes a hard surface.

Where the two types are combined, the timed fuse generally acts as a backup to the impact fuse.
Ideally a grenade will also have one or more safety devices - a classic, egg style grenade is made safe by the lever (also called the spoon) - once this is released, the timer starts and cannot be stopped. The function of the pin is to hold the lever in place.

Despite the demise of the stick grenade, modern grenades have occasionally been seen with bits of pipe or broom handle glued to the bottom to extend throwing range. Whether or not this is worth the effort is at least debatable.

Application

"Once you pull the pin, Mister Grenade is no longer your friend!"

The most common use for explosive grenades is in clearing the space behind an obstacle, whether that be the parapet of an enemy trench or the wall of a building. The operator arms the grenade and then throws or posts it into the space he wishes to clear where it bursts, attacking any targets present with blast and shrapnel. If the grenade is only expected to travel a short distance, the operator is advised to let any timer that is fitted run down as far as can be safely allowed to prevent the recipients of the grenade from returning it undetonated. Explosive grenades can also be used to attack groups of enemies in the open or as explosive charges to destroy structures as required. Large explosive grenades - or bundles of smaller ones - were often used to attack AFV before specialised anti-armour grenades became available.

"Flashbang"/stun grenades are used in the same way as explosives, but as a less-lethal alternative which incapacitates targets for capture or selective killing - e.g in prisoner rescue or policing situations, typically where there may be friendly or neutral units in the target area.

Smoke grenades are used to generate line of sight obstructions in the traditional manner and the useful secondary properties⁵ of white-phosphorous smoke are never-and-not-at-all used to suppress enemy infantry as well as blocking their LOS, making it a popular source of emergency smoke cover for ambushed troops⁶.

The majority of incendiaries are used more to destroy inanimate objects than as weapons in the truest sense of the word - thermite/thermate devices in particular are placed on top of (or inside) sensitive parts of the target structure and allowed to detonate. Bursting incendiaries such as white or red phosphorous are more used for starting terrain fires.

Chemical agent grenades are almost all⁷ CS style irritants and incapacitants and they and stingball grenades are mostly used for civil order work to suppress or disperse mobs. The customs and usages of warfare (mainly the Hague Conventions) preclude the use of chemical agents in conflict under the majority of circumstances.

Anti-armour grenades are an obsolete application of shaped charge armour piercing technology⁸, mostly introduced during WW2 and made obsolete in the course of the same conflict because they were unable to keep pace with improvements in vehicle armour.

Grenades can also be used for booby trapping - attaching a tripwire to the pin, or placing the grenade in a tin can and removing the pin are favourites. They can also be used as an anti helicopter trap (by tying a ribbon of cloth to the pin and leaving it on a suspected landing site where the ribbon will get pulled into the helicopter's rotors and arm the grenade).

Grenades are also very useful in night fighting - throwing a grenade generates no muzzle flash and thus attracts no return fire. The detonation, on the other hand, will often draw jitter fire from all sides, hopefully luring the enemy into a friendly fire battle whilst the thrower slips away⁹.

"Close only counts in horseshoes and hand grenades."

Sources

Bibliography

1. full source reference

Game and Story Use

• Very much a military weapon, grenades will cause a great deal of alarm if used in general business. Expect people in general not to be prepared for their use and to be very unhappy about it.
• Traditionally sane people ship grenades without the fuse/detonator assembly fitted. If a PCs is going to get roasted on a black market deal, he just gets the grenades…
• Some historical grenades have been as dangerous to the user as the target - a good proportion of the Japanese production in WW2 had an alarming level of variation in how long the alleged five second fuse took to burn down¹⁰ and the 'all ways' impact detonator in the Italian "Red Devil" grenades (also from WW2) might go off on impact … or a few seconds later … or when the grenade was next moved … or never … or even whilst it was being thrown. You could never tell…
  • Likewise, the British "sticky bomb" - an anti-tank grenade consisting of a substantial explosive charge covered in high grade adhesive. The idea was that the operator removed the safety cover, pulled the arming pin, stuck it to the target and sought cover - the problem being that it was heavy (and therefore hard to throw far enough to be outside the blast radius) and could stick to virtually anything, including the user, with the fuse burning…
• Recent news suggests that Ukrainian forces have given obsolete 1950s era anti-tank grenades a new lease of life by using drones to drop them on top of Russian AFVs.

Footnotes

1. Possibly shou liu dan

2. Generally siege warfare and naval boarding actions

3. The British Army introduced the Mills Bomb in 1915 as the "Grenade #5". By 1917 it had evolved into the "Grenade #36M". This was finally declared obsolete in 1972.

4. A note: the notching on the shells of "pineapple" style grenades has been demonstrated to have essentially no effect on fragmentation. Notching the inside does help, but is prohibitively expensive so modern grenades tend to rely on a coil of wire or ball bearings packed into the filler. The external notches are best used for their original purpose: making the grenade easier to grip when wet and/or muddy. There's also an interesting Austrian design (the ARGES 84, now only made on licence in Pakistan) that involves making the casing out of ball bearings in a resin matrix - the matrix vapourises on detonation and the balls appear to be released in a fairly even pattern. This isn't on general issue for anyone yet, but is interesting concept technology.

5. Specifically a rain of burning fragments that are very hard to extinguish

6. "Use your 'phos bombs to make smoke as close to the enemy as possible to create maximum obstruction to his lines of sight"

7. the Japanese produced a grenade that dispensed hydrogen cyanide vapour and had it on inventory during WW2 but evidence of its use is sketchy - captured training manuals suggest that it may have been intended as an anti-tank-weapon and some accounts suggest that it may have been used against British tanks in Burma on at least one occasion but official data is hard to come by.

8. At least the effective ones were, a variety of inferior designs simply used a contact explosion.

9. This arcanist has done this. Several times. If only with training grenades.

10. some captured examples tested by allied armourers seemed to have, effectively, a 0-second fuse