Spring-gun

To reduce fatalities by using this trap, non-lethal calibers are often used, or the spring-gun is fitted to fire less lethal ammunition.

For example, in the United States, most spring-guns are loaded with non-lethal caliber or shot to avoid liability arising from the use of deadly force in the protection of a property interest.

Posting clear and unmistakable warning signs as well as making entry to spring-gun guarded premises difficult for innocent persons, such as high walls, fences and natural obstacles, are significant ways to reduce potential tort liability arising from the spring gun's wounding of a careless or criminal intruder.

The subsequent outrage by the local population proved to be the final act of the Gunpowder Incident, leading Governor Dunmore to flee the city to a British warship and declare the Commonwealth of Virginia in a state of rebellion.

While they managed to avoid land mines, they did trip a spring-gun, killing one of Rene's friends.

[5] In 1990, one man in a group of four burglars was killed during a burglary by a spring-gun that was set up by a business owner in Colorado.

A spring alarm gun used as an anti-poaching device in the Bay of Islands in New Zealand. The device has a solid bracket for attaching to a post, and a triggering device with tripwire arms.
Non-lethal spring-gun as alarm
US patent for a spring-gun mousetrap