A 32-year-old Walton County man didn’t break any laws Saturday when he shot his lawn mower filled with an explosive, but he did lose his leg below the knee, the sheriff’s office said.

About 3:50 p.m., David Presley of Monroe shot an old lawn mower loaded with three pounds of Tannerite, according to the Walton County Sheriff’s Office. The lawn mower exploded.

His neighbor, Lydiah Mays, was inside when it happened.

“I heard him scream and so I came downstairs and we were all like looking out the front window,” Mays told Channel 2 Action News Thursday.

Two of Presley’s friends had helped him to a vehicle and had driven him to the bottom of the driveway in the 2200 block of Emmett Doster Road by the time deputies arrived. He was picked up from there and flown to Grady Memorial Hospital. He was missing his left leg.

It was not clear why Presley shot a lawn mower filled with an explosive, but Walton County Sheriff Joe Chapman told Channel 2 you’re supposed to put less than a pound of Tannerite into a target you want to shoot and stand at least 100 yards away.

Tannerite is the brand name of a binary explosive marketed primarily for making exploding targets for firearms practice, Walton County Fire Rescue Battalion Chief Craig League told the Loganville Local News. The mixture combines ammonium nitrate and aluminum powder. These powders are not flammable and are generally stable, when subjected to a lesser force than a high-velocity bullet, League said.

“You would’ve had to be on drugs or something to think it was a good idea to play with that and try to blow up a lawnmower,” Mays told Channel 2.

Presley used three times the recommended amount and only stood 25 yards away, Chapman told Channel 2.

Though League called the use of Tannerite dangerous for amateur use, League said serious injuries resulting from its use are relatively rare.

Deputies receive two to five calls a week related to the explosive.

“If you hear a loud boom and it shakes your home, your windows, and the china in your cabinets rattle around, then there is a good chance one of your neighbors is shooting Tannerite,” League said.