Site returns 500 for me. But this reminds me of my own coilguns I made as a kid. Disposable camera flash circuits connected to a set of solenoids wrapped around

Site returns 500 for me. But this reminds me of my own coilguns I made as a kid. Disposable camera flash circuits connected to a set of solenoids wrapped around a thin pvc pipe. Accelerated using a cascade triggering of each solendoid in series. Contact pairs directly in the pipe to close the next solenoid circuit when the metal slug reaches them.