The Gun Smith — C.J. Petit

Mack Smith had left his shop in Pueblo and was just an hour or so from reaching his brother's ranch for his annual visit when he felt the bullet slam into his head, and when his eyes finally opened, he found himself flat on his back on the bottom of a ravine. What the hell had happened? He was only a gunsmith, not a gunfighter. Who would want him dead?
When he discovered the reason for the mistaken assassination, it led to bigger changes in his life than he could ever have imagined, and the end to lots of other lives.