Specifics of building a multi-stage coilgun? Answered
So I recently decided that I wanted to build a coilgun. I already knew how they function, and after some light research, I've got the main design already laid out.
What I'm looking for now is some more detailed input on the exact power requirements, circuitry, etc.
Specifically: Firing a standard .177 steel BB, I want to use many small coils in series as opposed to one/few large ones. From my understanding, this will provide better end speed while keeping each coil's power draw relatively lower, and thus safer. (Am I right about this?) How many coils should I use, what would be overkill, etc?
Each coil will be triggered sequentially by a IR LED/photocell trigger system rigged through tiny holes drilled across the barrel. Will a simple on/off circuit suffice, or will the projectile pass by too quickly for the full charge to release? If so, I assume I need a system to trigger a full discharge when tripped. Correct or not, and if so, how?
I'm also considering fitting an extra gate at the end to trigger a circuit to bleed any remaining charge. Ideas on this?
What size of capacitors should I use, and how would I charge them? The only thing Google can seem to turn up is camera flash circuits, but I'd much rather have one tailor-built to the system's exact levels. I'm going to use a press/hold switch to charge them, and would like an automatic shutoff with an LED that comes on when they are charged, but turns off when I release the button. Kind of like a camera flash, actually.
I'd like to fit it with a re-chargeable battery. What sort of power is required here? How many firings would I likely get per charge, etc?
What sort of muzzle velocity can I expect? I don't want to kill bears with it, but soda cans would be nice. I don't want to waste my time fabricating it only to be able to stop it with my eyeball.
Lastly, are there any other points of concern or things I should know?
Thanks for any input, and if everything ends up coming together nicely, I'll be sure to properly document the process for everyone's enjoyment. :)