The recording and storing methods of ballistic data differ from each other in coordinates and formats. The current coordinate transform software lacks integration and operability. Combined with the task requirements, several common coordinate systems are summarized. The Bessel algorithm is improved to calculate the azimuth angle by using the transmitting point and aligning point in the earth coordinates. A process is introduced to convert flight altitude to launch coordinate y component through analytic geometry. An automatic ballistic data converting system is designed and implemented based on Matlab and applied to the practical work of the range. It is proved that the proposed method has high model precision to fix the offset within 2°, and has flexible operation for good user experience.