With the increasing demand for precision strike capability, the guidance transformation of conventional munition has become the main direction of munition research. The characteristics of high rotation and high speed of rotary stabilized missile make it a difficult point in guidance research. To solve this problem, a Spin-Stabilized Projectile with an aft control kit (ACK) is studied in this paper, and a dual-spin ballistic model (DSBM) is established. The accuracy of the dual-spin ballistic model is verified by actual flight tests. Based on the simulation model, the uncertainty sources of the trajectory parameters were studied, especially the uncertainty sources of the translational motion of the projectile’s centroid and the spin rate of the ACK. This paper provides the basis for the research of navigation, guidance and control of rotary stabilized missile with guidance stern.