Penetration efficiency and collateral damage characteristics of powder-type door-breaking projectile reinforced by non-metal inner ribs

In modern anti-terrorism operations, rapidly entering the room often requires breaching doors. Door-breaking projectiles can destroy locks or chains to facilitate this. However, traditional shotgun-fired door-breaking projectiles may cause collateral damage with their steel shot and fragments. So, this paper presents a new LCD (low collateral damage) breaking projectile. It uses an internally ribbed porous thin-walled non-metallic cylinder as the carrier and is filled with high-density metal powder. This structure ensures stability during firing, boosting penetration. After breaching, the metal powder quickly loses kinetic energy, reducing collateral damage. Ballistic tests and numerical simulations were done to study the breaching and collateral damage of this new projectile on steel targets. The effects of powder material, initial kinetic energy, and internal ribs were examined. The penetration and energy-absorption mechanisms of the porous cylinder with metal powder were analyzed. Results showed that a 2-order ribbed breaking projectile needs less initial kinetic energy and causes non-lethal collateral damage. This projectile, with its internal support, maintains stability during firing, enhancing penetration. After breaching, the metal powder's kinetic energy rapidly diminishes, lowering collateral damage. The study found that the 2-order ribbed projectile is efficient, needing less initial kinetic energy and causing non-lethal damage.