Annotation: Security forces weapons’ designing is an actual problem since antiterrorist and law enforcement activities appear more important issues in modern conflicts. Meanwhile, police and other security forces over the globe still apply combat weapons while providing law enforcement, antiterrorist, and other force domestic actions. Probable injuring of irrelative persons is well known problem of law enforcement and other security forces' firearms usage practice. The ways to advance firearms usage safety when there is risk of ricochet are considered. It is determined that projectile's material density influences on ricochet velocity. The procedure to provide safe after ricochet parameters of a projectile by projectile's material matching is designed. Common dependencies and methods of external and terminal ballistics are applied.