Sam Peckinpah nailed it pretty good in 1962 with Ride the High Country, then hit it dead center a few years later with The Wild Bunch.
And the previous film They Came to Cordura, one of Gary Cooper's last, touches on some of the same points.
To a bystander in the face of such men- there have been a few women in the club, too- particularly a bystander or observer who is unarmed, those beings might as well be an entirely seperate species. The lesson there is to not be one of those caught unarmed.
-archy-/-
...Tex never drew his gun, but he never lost a gunfight.