goodgrouper has a 338 Thunder an improved version of the 338 RUM with an ABS Carbon wrapped barrel and has reported extesively on it here and is very pleased HeetSekins has an ABS Carbon wrapped barrel on a 300 Win and is also very pleased. Fiiftydriver did the work on googroupers 338.
I believe the thread title is 338 Thunder project quite a lenghty thread, but the short of it is that is is very satisfied with the ABS Carbon Wrapped Barrel. He also used a Thermal Imaging Camera to prove how much faster that the ABS Carbon wrapped barrel dissapated the heat as compared to a all steel barrel
Check out web site: http://home.alltel.net/mdegerness/
or give them a call at: 402-890-2709
range it,check the wind, dial in correction, aim and only one shot