James Looney, 40, of Imperial shot himself while demonstrating the safety mechanisms on three guns, Sheriff Glenn Boyer told KSDK-TV, St. Louis, in a story aired Tuesday.
Looney put two guns to his head and pulled the triggers to show his girlfriend they would not fire with the safety catch in place, witnesses said.
The third gun fired, Boyer said, adding deputies believed Looney had been drinking.
Looney had planned to take his girlfriend to a shooting range the next day but insisted on her learning firearm safety the day before, Boyer said.
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