On a battlefield filled with distinctive sounds—the concussive WHUMP of artillery, the crack of rifles—nothing made quite an impression like the fifty, slower and lower than the staccato chatter of 7.62mm and 5.56mm machine guns. Anyone who’s ever fired a .50 caliber machine gun can instantly recognize its immutable THUB-THUB-THUB. While it may be the bass beat of death, I happen to find it soothing.