For a high school Physics project, I am supposed to create an electromagnetic device (like a generator, a motor, a Magnetohydrodynamic boat, etc.) I was thinking about building a Gauss gun, but was wondering if I could replace the individual magnets with electromagnets. I have a bunch of 1/2" by 2" bolts, and I have access to a bunch of magnet wire. I coiled wire around one of the bolts until it was about an inch in diameter, and hooked it up to a 9v battery. It's magnetic, and is able to suspend about two or three 1/2" steel balls in a vertical line. What do you suggest to make my electromagnets more powerful, and how should I arrange them to work optimally in a Gauss gun?