I made a air soft moartor that shoots about 100-150 ft in the air and it only costs about forty american dollars. I came up with this simple design myself and I don't want some dude that will copy my idea without reading this to build this. If you want the directions comment and ask for them. It shoots a nerf pocket rocket or anything you can fit in the barrel. The power sourse is a bike pump and you only need about thirty psi at the most. Takes me about 10 pumps with my bike pump.