I served with a draftee, Theodore Kopinski, a steel worker from Buffalo, NY who was on guard duty at an ammo dump after a string of unfavorable personal events, so he was not in a happy mood.
I was not there for this event but this is what several vouched was the story.
It was in a heavy rain when a military sedan pulled up to the gate. Kopinski opened the gate, checked credentials in the pouring rain and admitted the vehicle.
Rather than close the gate and then reopen it in the rain, he ducked into the guard shack to watch for the vehicle to return.
He saw it, went out to stand by the gate and wait for the vehicle to be checked out....sign said all vehicles must stop at the gate.
Well, the vehicle just went on through, throwing a big splash of muddy water on Kopinski. This was the last straw, it was told.
As was the procedure back then, he had been issued 3 rounds of 7.62 which were loaded, and fired a round at the back of the vehicle....and scored a hit on the trunk.
At his trial, he was charged with failure to close the gate, not with shooting, which, it was said, he was justified in doing since the vehicle did not stop.
Busted to E2 and probably other company level disciplinary action...don't remember.
Stopped issuing any ammo for guards after that too.