This strength protected the life of a Special Forces advisor in El Salvador when a Hartsfield knife stopped a 7.62×51mm NATO rifle bullet fired by a guerrilla. Hartsfield's blades were zero-ground, meaning there is no secondary bevel edge on the knife, which allows the knife to cut without parasitic drag.
This exceptional strength safeguarded the life of a Special Forces operative in El Salvador when a Hartsfield knife effectively deflected a 7.62×51mm NATO rifle bullet fired by a guerrilla. The distinctive zero-ground construction of Hartsfield's blades facilitated efficient cutting without hindrance.