A.K.A. Rail Gun
A coil gun is a gun that works by very rapidly firing high powered electromagnets to accelerate a metal
projectile. They generally use from 300 to 10,000 volts, and are pulsed for only a few milliseconds.
Due to the need for very high power for only a short period of time, they generally use capacitors as a
power source. The easiest (and cheapest) way to build a coil gun it to use a spool of ~28 gauge wire from
Radio Shack, wind a few hundred coils around a straw, and then use the capacitor from a used disposable
camera to fire it. Check your local Costco for used disposable cameras. They are usually free.
Premise: Make an entirely electric gun to accelerate a bullet to the highest possible velocity.
Danger Level (0-5): 2.5
Fun (0-5): 3.5
Cost Range: $1 to $5
More Detailed Sources: