Grenades have a very long history in warfare. They’ve been around in one form or another since about 700AD, when clay pots of Greek Fire were tossed at people and forts.
A common form of grenade used in later years was simply a cast iron sphere filled with gunpowder, and ignited by a burning fuse.
But the modern grenade as we think of it was an invention of World War One, where the ability to throw a small bomb into a trench, or from a trench into a crowd of troops, was greatly appreciated. The first really successful hand grenade was the British Mills Bomb. It’s great improvement over other grenades was its time fuze. By using a percussion cap to light a powder fuse, the Mills Bomb would consitently explode after a set interval, typically 5 seconds. The striker for the percussion cap was held in place by a lever along the side of the grenade, which was in turn held in place by a pin with a pull ring.
Thus, early on, the model for nearly every hand grenade was set. Almost all hand grenades share some recognizable traits with the British Mills Bomb. Like, the US Mk2 “Pineapple” grenade that saw service throughout WWII and Korea.
The only significantly different design grenades were the German “potato masher” grenades. These consisted of an explosive can on the end of a long wooden handle.
The Mills Bomb/Pineapple grenades and the “potato masher” grenades reflect two somewhat different philosophies about how grenades should be used. The first group are often referred to as “defensive grenades” while the second are sometimes called “offensive grenades.” The distinction lies in the fragmentation pattern versus the throwing range of the grenade. Simply put, the fragments from a defensive grenade would be dangerous to the thrower even if he threw it as far as he could. He would need to take some type of cover when throwing the grenade. The potato mashers, on the other hand, relied more on the blast of the grenade to cause casualties and could be thrown from an exposed position, as one might find themselves during the assault. The only problem was that they didn’t cause nearly as many casualties. The stick grenade was adopted by the Japanese and later by the Chinese communists, and by the Viet Cong and North Vietnamese Army. There are many stories of stick grenades detonating very close to our troops who survived with little or no permanent injury. The same cannot be said of people who have had a fragmentation grenade explode next to them. For this reason, the Soviets adopted a fragmentation type grenade.
You’ve probably noticed the grooves in the casing of the fragmentation grenades. That was designed to ensure the even distribution of fragements when the grenade exploded. The only problem was, it didn’t work. It would take a long time before anyone realized that the way to ensure even distribution of the fragments was to groove the inside of the grenade. Since that is difficult to do, many grenades now wrap the explosive charge with wire, inside the casing, or use BB’s or small ball bearings to provide shrapnel.
The current US grenade, the M67, is spherical, and has embedded fragments to increase its lethality. By keeping these fragments lightweight, they also reduce the effective radius of the grenade to about 5 meters. This makes it somewhat safer to throw. Most soldiers can throw the grenade about 30-35 meters (very roughly, about 100-110 feet). Fragments and parts of the fuse can travel up to 230 meters, so obviously, soldiers still need to take some cover when throwing a grenade.
Notice in addition to the pin holding the lever that there is a small wire safety clip. This serves as a secondary safety device. It is removed by a flick of the thumb before pulling the pin and throwing the grenade.
Some Not Safe For Work Language, so turn down the sound.
As an aside, the Army uses grenade simulators in its excercises to simulate the noise and smoke of a grenade without the fragments. These are basically giant firecrackers.
Fragmentation grenades aren’t the only types in service. Smoke grenades are commonly used as well. Some smoke grenades produce a cloud of white smoke to screen troops from observation. Colored smoke grenades are used for signalling or to mark a position.
Thermite grenades are used to set captured equipment on fire. After Operation Desert Storm, we traveled throughout southern Iraq and destroyed abandoned Iraqi vehicles by placing a thermite grenade on the engine block. The intense combustion would melt the engine.
And has anyone seen a Democratic protest without seeing tear gas grenades?
One of the main drawbacks of grenades is their limited range. We’ll take a look the solution to that problem when we cover grenade launchers.
UPDATE: Commenter Aussietrias has this to say:
Must be interesting to train their use because they’d have to get them over their fear yet not so much as to encourage complacency.
Actually, that is a real problem. Most grenade training is done with practice grenades that have a working fuse, but no explosive. And for the most part, grenade training is somewhat boring. Once you’ve done that, you get to throw two live grenades in basic training, and at later trips to the range. I found that pretty boring as well, because you don’t get to watch the explosions. Still, a boring explosion is better than no explosion at all.
But the problem is real- you can easily blow yourself up. Take a look at these guys.