Effects of Cylindrical Structure on Bullet In-Bore Action Process

Abstract

Abstract To explore the effects of bullet cylindrical difference on in-bore dynamic engraving resistance and muzzle swing, a finite element model of bullet-barrel interaction is built. With the proposed model, real bore bottom pressure curves are obtained through experiments. In the numerical simulation, the in-bore motion processes of two all-copper bullets with different cylindrical structures are reproduced according to the real bore bottom pressure curves, so as to qualitatively analyze the relationship between bore pressure curves and bullet in-bore motion. The association between curve inflection points and bullet motion is identified, and the engraving forces of the two bullets are found to exhibit roughly the same trend. In addition, there is an abnormal phenomenon that the bullet with a shorter engraving length should have a larger engraving force. This is due to the interaction between the shape of bore pressure curves and the engraving process, as well as the larger muzzle swing caused by straight slotted structures that have a shorter engraving length. The findings of this study can provide a basis for the design of internal ballistics and the further analysis of the effects of in-bore motion on external ballistics.