Ballistic knife

A ballistic knife is a knife with a detachable blade that can be ejected to a distance of several yards (one yard equals approximately one metre) by pressing a trigger or operating a lever or switch on the handle. Spring-powered ballistic knives briefly gained notoriety in the United States in the mid-1980s after commercial examples were marketed and sold in the United States and other Western countries. Since then, the marketing and sale of ballistic knives to civilians has been restricted or prohibited by law in several countries.

History and usage

In its spring-propelled form, the blade of a ballistic knife is theoretically capable of being fired to an effective range of around 5 meters (about 16 feet) at a speed of 63 km/h (39 mph). Ballistic knives using compressed air or gas propulsion to fire the blade can be made somewhat more powerful, and do not suffer from spring fatigue over time.

In addition to spring, air, or gas propulsion, the blade of a ballistic knife may also be propelled by an explosive charge, such as a blank pistol cartridge.