Cor-Bon's Urban Response Load ammunition is designed for use in close-quarter urban environments such as subdivisions, apartment complexes, and mobile home parks. The .223 Remington 55-grain Urban Response JHP has a specially designed thin jacket with a soft lead core for high velocity, low penetration, and minimum ricochet. It's compatible with all AR-15/M-4 rifles with either 223 Remington chambers or 5.56 NATO chambers.