Joseph V. Loughrey, 44, of Sharpsville, brought a 9mm Taurus pistol and a rifle to Trig's Reloading Den in East Lackawannock Dec. 8 to try to sell them, but the store owner said she didn't buy guns.
Loughrey said he had emptied the handgun but hadn't realized a bullet remained in the chamber as he carried the gun while getting back into his pickup outside the store, the Pittsburgh Post-Gazette reported.
Loughrey's son, Craig Allen Loughrey of Fredonia, was in the passenger seat when the pistol fired and the bullet struck him in the chest.
Police had said Loughrey could be charged with manslaughter or negligence. The Mercer County state's attorney's office said no charges would be filed, the newspaper said Wednesday.