Does anyone have an instructable for a coil gun using multiple coils?

If anyone could link me to a site that has a circuit diagram for a coilgun with multiple coils I would be much obliged, as I have designed what I think the circuit should look like, but I am not 100%, and so before I waste time, money and effort on building this thing I want to check that it's right. If you can link me to an instructable-esque site, that would be awesome, but anything is fine.