Blake Wardell, 26, was with a few friends at a home in Anderson County, S.C. when they decided to try on the bulletproof vest and have someone shoot it, deputy coroner Don McCown told Fox affilliate WHNS.
Wardell bled to death after the bullet missed the vest and wounded him in the chest.
His friend, Taylor Ann Kelly, 18, has been charged with involuntary manslaughter, according to police.
Kelly could face up to five years in prison.
Police have classified Wardell's death as a homicide and said drug and alcohol use were not involved in the incident. Police were still investigating the shooting.