Many may know the story of Jon-Erik Hexum, I didn't so here you go. He was born in 1957 to Norwegian parents and he was a model/actor. He was in Voyager from the Unknown, Phineas Bogg in 'Voyagers!', The Bear (1984), TV Movie with Joan Collins in 'Making of A Male Model,' and his CBS TV show 'Cover Up,' a program about a pair of fashion photographers/models who were actually secret agents.
On the set of 'Cover Up,' Hexum died after shooting himself in the head with a prop gun loaded with blanks , Hexum, who played a weapons expert, was said to constantly be playing with the guns as if they were toys.
He didn't know the blanks use paper or plastic wadding to seal gun powder into the shell, and that this wadding is propelled out of the barrel of the gun with enough force to cause severe injury or death if the weapon is fired at point-blank range. His last words are said to be "Let's see if I get myself with this one."
After several hours of surgery, he was pronounced brain dead and his body was flown to San Francisco with his mom's permission for organ donation. His heart was transplanted to another man after his death.
You can watch a bunch stuff he was in on YouTube