West of the Cimarron - John Manville

When Lance Turner took on the job of marshal of Vengeance, he knew he would have to rid the town of the lawless elements to make it a decent place for honest people.
But the citizens forgot to tell him that nobody would back him when it came to a showdown with Wayne Patten, the big cattle boss.
There was no posse in Vengeance, no one to ride out with Lance against the hired killers sent by Patten to destroy the marshal.
Then came the showdown, with the lawless bands on the one hand and a lone man on the other...