In 1860 he appears as Oliver Salmons, born 1813, in Reed Creek District of Hart County GA. Based on his age and family, we could expect to see his son Benjamin in the Confederate military but not Oliver.

In any case, I don't find the name among Georgia Confederate soldiers. More interesting, he's not in the 1864 Georgia militia register, which strongly suggests that he's not in the state due to death or removal before that time.