Kermit,
I took a look at the CLA "chunk gun" and have to believe that Hud Huddleston just built a heavy Kentucky style rifle. Perhaps it was intended to be a match rifle but it certainly doesn't contain many of the specialties I would have included. The stock is more of an offhand style than chunk and the barrel would most likely have been heavier. 12# is pretty light, not unheard of, for a dedicated chunk gun.
Mark