Follow the Texans — Marshall Grover

In the Arizona Territory, Bosworth County was in a state of tension, its citizens living in fear. Six soldiers and two civilians had been wantonly murdered. An entire shipment of repeating rifles, capable of swift and accurate fire, had been hijacked.
Army Intelligence was baffled. The county law officers were becoming desperate. And then, as quietly as a raging Texas tornado, Larry and Stretch arrived. The West's rowdiest troubleshooters were buying into a grim intrigue ready to risk their lives in a fight to the finish against the forces of lawlessness.

Leonard Frank Meares (February 13, 1921 - February 4, 1993)
Sydney born Len Meares aka Marshall Grover, published around 750 novels, mostly westerns. His best-known works feature Texas trouble-shooters Larry and Stretch. Before starting to write, Meares served in the Royal Australian Air Force, worked in the Department of Immigration and sold shoes. In the mid-1950s he bought a typewriter to write radio and film scripts. Inspired by the success of local paperback westerns, he wrote Trouble Town, which was published by the Cleveland Publishing Company in 1955.
His tenth yarn, Drift! (1956), introduced Larry Valentine and Stretch Emerson. In 1960, he created a brief but memorable series of westerns set in and around the town of Bleak Creek. Four years later came The Night McLennan Died, the first of more than 70 westerns (sometimes called oaters) to feature cavalryman-turned-manhunter Big Jim Rand.