Grit and Bullets was inspired by Microlite2020 which in turn was inspired by Microlite20. If you are familiar with Microlite20 the primary difference is the replacement of the four (or in some versions five) set Skills with Backgrounds chosen by the player. Also, rather than races there are Classes.
It seems to me that there are three sub-genres of Western themed role playing games:
The core rules of Grit and Bullets was designed with realism in mind, although I don’t know how realistic any RPG can ever be. The Characters are heroic but not super human. They are competent but not incapable of error and failure. In fact the Characters are rather more vulnerable as compared with other well known role playing games, and can suffer debilitating wounds that take time to heal. However, if you want to play a more Cinematic or Weird West game there are optional rules to be found in the Appendix area at the end of this booklet that hopefully will provide you with what you are looking for.
Grit and Bullets on DrivethruRPG ($4.99)