In order to provide a reference for studying the problems about projectiles entering water problem at high speed across the medium, this paper uses numerical simulation software to conduct a numerical simulation study on the turning process of the elastoplastic projectile with geometric symmetry and series of head cutting angles. The force mechanism of the projectile’s turning into the water is analyzed, and the influence of the cutting angle on the projectile’s entry into the water is revealed. Finally, we found out that the geometrically asymmetric structure can make the projectile’s underwater movement more smooth, also, within a certain range, the greater the cutting angle is, the smoother the projectile’s underwater turning process is.