In this paper, a study was made to improve the speed of the coil gun. Coil guns are being actively studied around the world because they are based on the development of low-cost space launch vehicles. In order to maximize the speed of the launch vehicle, this study adopted the largest coil of the AWG standard. In order to select the optimal number of turns and the length of the launch vehicle, matlab, a commercial numerical analysis program, was used to select the number of turns and lengths that can maximize the speed of the launch vehicle.