BILLINGS, Mont. (AP) — The superintendent of a rural Montana school district says he was showing students his black powder muzzleloader when he accidentally fired the weapon into a classroom wall during a history lesson.

Dwain Haggard, who used to be a Civil War re-enactor, was showing the gun to five students in Reed Point High School's American history class Friday when it fired.

No one was injured, and Haggard says he can't explain how the weapon was loaded.

He says he usually fires a cap during the demonstration, but this time there was a loud bang and the room filled with smoke.

The ball shot through the "o'' in the word "North" on a wall map.

Haggard says none of the students' parents was upset with him. He described the incident as "bitter irony" because he has tried to increase safety in the school district west of Billings.