Cord, a gunslinger hired to do jobs outside the Army's jurisdiction, and his partner Pico are sent by the Army post commander to to find who is selling Indians rifles and ammunition.; Cord and Pico are sent across the Rio Grande river into Mexico to hunt down a renegade Army sergeant who is using "by-the-book" Army tactics to lead a gang of bandits.; Cord, Amby, and Billy spend the night in Amby's store to find out who's been stealing chewing tobacco from her storeroom.; Facts about Indians' ingenuity in converting discarded Army rifle shells into reloadable ammunition.; Facts about civilians who lived on western Army posts.