The anti-rethrow performance， which is realized through rapid ground motion of the projectile， is a critical operational effectiveness indicator for combustion-type anti-riot ammunition. To effectively simulate and evaluate this performance， a gas diffusion model within the projectile cavity was established based on the typical structure and composition of an anti-riot colored smoke projectile. The gas velocity and pressure at the orifices were obtained using computational fluid dynamics （CFD） methods， from which the thrust was calculated via the jet thrust formula. Subsequently， a dynamic model of the projectile ground motion was developed and solved using finite element numerical simulation to analyze the movement of the ammunition. To further validate the simulation accuracy and compare the effects of different projectile structures on the anti-rethrow performance， experimental measurements using actual projectiles were conducted to analyze the projectile motion trajectory， and additional simulations were performed to investigate the influence of varying orifice numbers， diameters， and inclination angles on the projectile’s travel distance and vertical displacement. The results demonstrate that the numerical simulation results for the typical projectile structure agree well with the experimental data， with only a 4.96% discrepancy in projectile displacement. During the numerical simulation， the variations in the orifice outlet velocity， orifice wall pressure， and cavity pressure tend to stabilize 6 s after ignition and smoke generation， which corresponds to the projectile entering a steady rotational motion after 6 s under actual operating conditions. Furthermore， the orifice diameter and the number of orifices significantly affect the projectile motion process： a reduction in orifice diameter tends to induce significant irregular oscillations in the vertical displacement curve； a smaller number of orifices leads to higher orifice wall pressure， higher outlet velocity at the orifice， and consequently greater thrust. Based on a comprehensive consideration of the anti-rebound performance， a configuration with four orifices， a diameter of 3 mm， and an inclination angle of 40°–50°， or a configuration with three orifices， a diameter of 3 mm， and an inclination angle of 40°-50°， is recommended. This study can effectively guide the future design of the anti-rethrow performance for such ammunition.