I did an experiment using an air cannon to find the drag exhibited on a cylindrical projectile using different mass/density and pressure/velocity. However, I was not able to obtain light gates at the time, so now I have no measurement for velocity. This is necessary for my results, and I was wondering if anyone could help me in calculating it. I have all dimensions and volumes of the components to the air cannon and projectile, distance and time of flight of the projectile, air pressure within the gas chamber and launch angle. If anyone could help me calculate the exit velocity of the projectile it would be greatly appreciated.