Retribution at Black Gap by the late British author John Russell Fearn (
ISFDB,
Wikipedia,
SFE) is his vintage standalone western historical action adventure novel, this one another town takeover story, as a murderous man takes charge of a newly-discovered gold mine by offing the owner, and recruits local labour with the help of assorted ne'erdowells and his reluctant stepson, who of course decides to betray him for the beautiful daughter of an opposing rancher, as you do, only to find that his evil stepfather's control may be harder to overturn, free for a limited time courtesy of publisher Endeavour's Pioneering imprint.
This was originally published in 1950 by Scion under the title
Bonanza, and was later reprinted by Robert Hale as part of their Black Horse Western line using the pseudonym Frank Russell.

Also, I hereby point you all to
Bob the Angry Flower's Quick Guide to the Apostrophe, which sadly, the cover designer could have used, even though technically, the proper non-apostrophization of “whose”, a vestigial case form, is not covered by it.
Currently free @
Amazon (available to Canadians & in the UK and pretty much everywhere else worldwide that Amazon sells, since this is being done via their KDP Select exclusive or else program)
Description
Kirk Stebbings is a killer with big ideas…
After murdering the owner of a newly discovered gold-mine, he sees his chance to seize control and hit the big-time.
Fearless and without mercy, he takes over the ramshackle little town of Black Gap, Arizona.
Recruiting local workers to exploit the mine, Stebbings is aided by sundry gun-hawks and – reluctantly – by his young stepson, Hank.
But not everyone is going to sit back and watch Stebbings continue his brutal reign.
He soon meets opposition from local rancher and preacher Bill Westlake, and rival saloon owner Rex Carbine.
Westlake vows to smash Stebbings’ golden grip over the territory, restoring peace, law and order to the land.
But as their campaign to undermine Stebbings gets underway, they are met with violent and murderous reprisals.
Upon meeting the beautiful young Ruth Westlake, Hank abandons his evil stepfather and decides to join Westlake in the mission to take down Stebbings.
But Stebbings is a man who will stop at nothing to keep his tight hold on control.
And with the local sheriff and townspeople under his command, are Westlake and his family fighting a losing battle?
A classic tale of the American West, the fight between good and evil plays out in Retribution at Black Gap, but who will triumph?