Coil gun

A coil gun is similar in concept to a rail gun that lacks rails. It works on the principle of magnetic levitation. A projectile which has a strong magnetic field is placed inside a long chain of hollow coils of wire. When a coil is switched on, the object experiences a force pulling toward the center of the coil. When the projectile nears this point, the coil is switched off and the next coil switched on.

Like rail guns and ram accelerators, coil guns have been proposed for use in delivering payloads to space.