Killing Time by British author Jack Giles (
Fantastic Fiction) is his standalone historical western action adventure novel, this one a complex tale of wrongdoing and revenge involving lawmen and robbers and murder and a self-appointed Grim Reaper

in unexpected combinations, apparently very twistily intertwined according to the customer reviews, free for a limited time courtesy of publisher Endeavour Press' Pioneering imprint.
This was originally published in 1994 by Robert Hale under the title
The Fourth Horseman.
Currently free @
Amazon (available to Canadians & in the UK and pretty much everywhere else Amazon sells worldwide, since this is being done via their KDP Select exclusive-or-else program)
Description
Friday The Thirteenth.
Close to midnight.
The Government Agent Willard Dull is reading a book at the hotel bar when a man in black comes in.
As the stranger retired to his room, Dull took a look at the register.
The man had signed himself as 'Death' from 'Hell'.
Before midnight chimed, two men were dead, both killed by the man in black.
Dull suddenly realises that all his plans to trap a gang of payroll robbers are about to fall apart — unless he can stop Death from reaping a grim harvest…
Killing Time is a tense and thrilling Western about justice in an unforgiving land and time.