In order to suppress or eliminate gyro instability to improve the flight stability and hit accuracy of spinning projectile, the numerical simulation of virtual flight of M852 projectile and Basic Finner missile model was carried out by using coupled URANS equation and rigid motion equations. The computation results fitted well with the test results. Different initial yaw angle had little effect on the pitching / yaw cycle of M852 bullet, but the larger the initial yaw angle was, the larger the motion amplitude, and the larger the lateral deviation, the faster the speed decreased. For Basic Finner model with low speed rotation, the flight characteristics of different emission velocities were different, and it was embodied in the aspect of velocity evolution, displacement fluctuation and cone amplitude, etc..