Only once I have had to threaten with a gun. 20 years ago there was a knock at our front door and it was a woman saying she had been raped and that 3 men had her car. She got away by telling them she needed to go to the bathroom and was let out of the car outside of our place. I rang 911 and reported it. A few minutes later there was a knock at my door and it wasn't the police. It was the 3 men who she accused of rape. I just tapped the barrel of my 9MM Beretta on the frosted glass on the front door and told them to leave or I would shoot. They left. The 9MM was actually broken at the time and wouldn't have actually worked, but they left and were stopped a couple of minutes later by the police. But I could have probably tapped anything metal on the glass and threatened to shoot and they would still have gone away.