Author's note #1: In the late 1800s, a Gunfighter was known as a "Shootist."
Author's note #2: This story is written in a simulation of the dialect of the period. Therefore, do not be overly concerned about verb tenses, etc. Words are spelled in the modern manner, so that should make the story easy to read. In general, the only contractions will be "ain't" and "y'all." Also, "must of" was in standard usage over "must have."