Let me know what you come up with for a power supply, most rail guns need something on the order of a nuclear reactor to get them up to speed.
Most rail guns are also shooting something fairly heavy. I’m thinking something light, about the size of a pellet gun pellet. I was also planning on using ferrous material for the ammo, so it wouldn’t need a separate “rail”.
But, right now it’s just a sketch on a napkin. (Ok, several sketches on several napkins.) My current living situation doesn’t allow for building prototype weaponry. I’m working on changing that.