I know how to make it bounce. What exactly do you need it to do? Explode after a certain amount of bounces or explode after a certain amount of time? And how high do you want it to bounce?
Also the Bullet Shape doesn't need a joint, unless you want to animate it. Unless a collision mesh is added everything happens at the central axis (at the x=0, y=0, z=0 point in Milkshape)