Ballistics gelatin, also known as ballistics gel, is a analog for the tissue of living organisms which is made from gelatin which is dissolved in water, allowed to set, and then chilled so that it becomes very dense. As the name implies, ballistics gel is used to test firearms, although it is also used in experiments where people want to approximate the amount of damage something will cause to a body without actually using a body. Several companies manufacture ballistics gelatin to very exacting standards for organizations like the Federal Bureau of Investigation (FBI), and it is also possible to make a similar version at home.
When ballistics gel is made, the proportion of gelatin to water is designed to produce a block of gelatin which will closely mimic the muscle tissue of an animal. In some experiments, bones from pigs or other animals will be suspended in the gelatin while it sets so that the experiment more closely mimics a real body, since most bodies do not walk around without bones. After the gelatin has set, some organizations test it with a standard firearm to ensure that it has been made to the proper specifications; the organization uses existing data on bullet penetration to calibrate the ballistics gel.
One of the most common uses for ballistics gel is in testing of new firearms. A firearms company may want to see how effectively a weapon will penetrate a body at varying distances, for example. Ballistics gelatin can mimic the composition of a human body, but it is also used in testing of firearms and bullets designed for other animals, ranging from birds to elephants. Bullets are also designed for a wide range of uses; a company might want to design a bullet that penetrates without causing a great deal of damage, for example, so that the bullet could be used as a nonlethal device.
Organizations may also use ballistics gel when they try to understand the mechanics of a crime. Confiscated weapons may be fired into ballistics gel to obtain bullets for study, for example, or an organization might be curious to know more about the conditions when a bullet was fired. By using blocks of ballistic gel as human stand-ins, investigators can get a better picture of a crime scene, and they may learn more about the positioning of the victims and the weapon.
If you'd like to try your hand at making ballistics gel at home, start by purchasing gelatin powder from your local store. Mix up a solution of one part gelatin to nine parts water according to the instructions of the manufacturer, and chill for around 36 hours to allow the gelatin to completely set. Since gelatin does not smell very pleasant, you can add cinnamon or another pleasant smelling spice to the mixture. This recipe is not as precise as that used by ballistics professionals, but it is a pretty close approximation, and you can always eat it if it doesn't turn out right.
Incidentally, this wiseGEEK author recommends that you take a firearms safety course before handling any weapons, and that you observe basic firearms safety and etiquette, whether or not ballistics gel is involved. Please remember this cardinal rule of gun safety: never point a gun at something you don't want to shoot.