How can I get a higher projectile velocity for my coilgun?

I made a coilgun using 8 capacitors of 50V and 4700uf connected in parallel and powered by 4 batteries of 9V each. The coil is wound around a plastic tube over a length of 2 cm. However the projectile (an iron nail of 1 inch just popps out of the tube). How can I fire it at a higher velocity?   

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More power. You have a decent capacitor bank but your not giving it enough power. A single capacitor on that setup will give you the same result. You need to boost the voltage to give you what you need. A single disposable camera flash circuit with it's single capacitor and being charged off an AA battery will give you a better kick than your current setup.
coilgunfreak (author)  mpilchfamily4 years ago
Do you suggest adding one more 9V battery in series?