The development of a bullet simulating projectile for body armor testing

The standardized ballistic testing methodologies for Personal Protective Equipment that are currently used, incorporate the use of common mass production projectiles. The discrepancies in their attributes, material composition, geometry, assembly, production tolerances, introduce extra variability in their responses, for the stochastic physical phenomenon, that is ballistic impact. A prototype of a Bullet Simulating Projectile (BSP) was developed for replacing commercial 9mm projectiles, strongly limiting the unknown variables that normally manifest themselves in ballistic impact tests. The effectiveness of the proposed BSP design was examined against soft protection targets in terms of penetrability and induced behind armor blunt trauma (BABT). The proposed BSP design was used versus multilayered non-crimp aramid fabric packs backed against Weible red plastilina. The resistance to perforation and the BABT were measured and compared with commercial 9mm projectiles. A finite element model was developed for investigating the local response of multilayered non-crimp aramid fabrics against the 9mm Parabellum projectile and the BSP. The fabric is presented as a dual ±45o angle-ply yarn based model with its yarns being interconnected using cohesive formulation elements. The results were compared with the experimental data.