Bullets for a Ranger, by Bradford Scott (epub/Kindle/pdf)
Ghosts range -- fearsome figures in gleaming armor, spirits of the conquistadores -- are striking terror into the herdsmen of Texas' Matagorda Bay country.... But maybe, a skeptical Slade told himself, they're not ghosts -- just smart owlhoots wrapped in tin plate.... So the Ranger ace went "ghost"-hunting -- with hot lead and fighting fury!
But Slade didn't know how close he himself would come to being made a ghost....