Assault Riffle Bullet-Experimental Characterization and Computer (FE) Modeling

This paper describes the development of a finite element model for the 7.62x39 mm mild steel core (MSC) bullet. The derivation of the numerical model is based on results of compression testing performed on bullet components and bullets. The material constants needed are obtained using an iterative approach, where numerical models of the compression tests are carried out to match the force displacement response of the tested structures. Later, these set of constants are refined by comparing predicted deformed shapes against those observed during ballistic impact experiments. Numerical simulations of the 7.62x39 mm MSC bullet impacting a semi-infinite rigid plate are carried out over a range of impact velocities, and the predicted deformed shapes compared to experimental shapes obtained with the help of high speed photography. Soft recovery of cores and jackets are also used to perform comparisons with predicted results. It was found that our constitutive and damage models, implemented in ABAQUS Explicit, were able to accurately predict deformed shapes and failure modes without any predefined defects in the element mesh.