Abstract: To study the high-strain-rate plastic deformation and fracture failure of the projectile belt at the slope during the dynamic impact extrusion process of cased telescoped ammunition, considering the particularity of the secondary ignition of the cased telescoped ammunition and the combustion of the gunpowder program, with the bottom pressure of the projectile and the one-load speed of the projectile obtained from the test taken as the initial boundary conditions of the numerical simulation model, a three-dimensional finite element model was built based on the structural characteristics of the body tube and the cased telescoped ammunition, large deformation and damage effect of the material. Based on the LS-DYNA software, the dynamic engraving process of the cased telescoped ammunition was studied using an explicit numerical calculation method. The variation law of projectile impact extrusion resistance was obtained, and the forming process and stress strain characteristics of the grooves on the surface of the elastic belt were analyzed. The results show that when the copper belt of the cased telescoped ammunition is violently engraved into the slope chamber, it undergoes a process from elastic deformation to plastic deformation and finally to fracture failure. When the elastic belt is completely engraved into the body tube full depth rifling, the entire dynamic impact engraving process is over, and a deep groove is formed on the surface of the elastic belt, which closely adheres to the body tube rifling, during which the impact engraving resistance shows a strong nonlinear change.