One of the most outstanding reenactor websites on the internet is dedicated to this storied unit, the 26th Regiment North Carolina Troops.
Your ancestor, as well as, many of his relatives are listed on the rosters on this site and there is a lengthy and in-depth history of the unit also available.
I would suggest you contact their unit historian who should certainly be able to give you more info on "The Chatham Boys".
26th Regiment North Carolina Troops
BTW, I was watching Battlefield Detectives on Monday on the History Channel and they had a program dedicated to Gettysburg. In one scene a park ranger/historian was standing on the edge of Willoughby Run at Gettysburg telling the story of the loss of four 26th NC colorbearers. The rocky-bottomed, creek is no more than twenty feet across in the picture and in this short space four men fell and passed the colors of this unit. I know the history of the 26th at Gettysburg and its horrific losses, but this visual of such tremendous loss just by the colorbearers in such a small place, really brought home what a terrible day July 1st, 1863 was for these North Carolina boys.