Gauss Gun (aka Coil Gun)
A Gauss Gun is a weapon that fires projectiles using electricity instead of combusion or air pressure. The basic concept is to dump a ton of energy into a coil as fast as possible, generating a strong magnetic field to “suck” the projectile through the coil. The trick is to design your coil properly so that the coil is off by time the projectile leaves it, or you end up with a giant, non exciting solenoid. The cheapest way for the hobbiest is to use large capacitors and a large circuit breaker for a switch. If you have some money, Silicon Controlled Rectifiers (SCRs) are the way to go, allowing less energy to be wasted during switching.
This is my overall setup:
The 3.5kj capacitor bank cart:
Closeup of the parallel SCRs and back EMF Diode:
My water resistor, consists of aluminum foil and salt water. Allows discharging the bank slowly and then keeping it discharged:
The setup for shooting things: