Multi STage Coil Gun

[brandonND]

For the Science fair this year I am making a Multi Stage (5 to be exact) Coil Gun, I have it all planned with diagrams, sketchs, and most of the parts gathered, except for the part of the circuit that turns the coil off automaticly so the next one can grab the projectile therby increasing its speed. The total power that my coil gun will be running on is 63 volts and 75.3 amps/hour. Each stage will run at 10.5 volts and 12.55 amps with the last one being double that. I would like to use batteries not capacitors. The batteries and wires will be on the inside of cage made of smaller plastic tubing running through the circular discs of plastic that will hold the wire in place. It will be controlled by a single button and a set of two switches on a control box that will be connected by about five feet of white tubing. It will be like a turret, as I will make it on a slight slant and it will be blanaced on four legs that I can rest on a desk or w/e.

 

I have everything planned out except how to wire it so that each section shuts down as the "bullet" passes through. I have already made a single one but Making one like this is my current project and short of wiring up lasers I cant see how to do it. I think I may be able to get it so tha the diode can cause it to break, but Im not sure how.