Max Brand 
The Big Trail [EPUB ebook] 

They said Big Tom Fuller was dumb as a post. They said he couldn’t pour rainwater out of a boot if it had instructions on the heel. They said he couldn’t hold a job if it had handles. But he was strong as an ox and mighty handy with a gun when he had to be.

Then he met Oliver Champion—a lone rider in a lawless land. Champion was following a dream, looking for a place he’d never seen. And someone like Big Tom would come in mighty handy in case of trouble. So he hired Fuller for more money than the kid ever made. And soon the two were riding a bloody trail of strange justice.