A kid I knew did this. He was about 10 or 11 at the time. Took an unloaded (and totally illegal) hand gun from his father's drawer and went hitch-hiking and when someone pulled over, he pulled the gun on him. Guy took him in the car and drove straight to the police station.

Turned out he was trying to run away from his very abusive and neglectful parents and figured the gun would help him "make his way"

The benefit that came out of it was that social services were alerted and he was removed into foster care.