A projectile launching apparatus and methods for use with an aerosol spray device containing a flammable liquid. The apparatus comprising a chamber and a tube, the tube fixedly attached to an opening in the chamber. Inside the chamber is a spark gap connected by an electrical cable to a spark power source, the cable having sufficient length to permit the spark power source to be located away from the chamber. A method comprising the steps of sliding the projectile over the tube; spraying some of the flammable liquid into the chamber; activating the spark power source, thereby igniting the mixture of air and flammable liquid, the ignition of the mixture of air and flammable liquid thereby propelling the projectile rapidly away from the projectile launcher apparatus.