Giant on Horseback — Lewis B. Patten

Ruthlessly, Clint Morgan had built up the giant Sombrero Ranch until it was the biggest and the best in all the New Mexico Territory. But a shadow fell over the range land when Clint's bastard son, Morgan Lamb, arrived from the East, bringing with him painful memories from the past. Drunk with hatred and a lifelong thirst for revenge, Lamb's stepfather tries to break up the Morgan empire. HIs wife's son by another man would get hell--or nothing at all, and he'd hire as many gunslingers as necessary to do the job.