The Single Action Shooting Society is the umbrella organization with several disciplines. You will find different rulebooks (Handbooks) for Cowboy Action Shooting, Wild Bunch Action Shooting, and Cowboy Clays.
There are separate Forums for CAS and WBAS because the rules in many cases are different. The handguns are different, the round counts are different, the pistol load parameters are different.
If you post a question on the Wire Bunch Forum, it will be answered. There are a lot of experienced, helpful shooters there. Sign up! There is a lot of helpful information already posted there.