I don't really have a dog in this fight in regard to barrel thickness and accuracy. However, this whole discussion made me curious and so i did a google search using "accuracy of thick rifle barrels." You do get quite a bit of stuff indicating that a thick barrel tends to be more accurate for the reasons discussed by Ridge Runner. I have attached one such discussion below. Dunno how expert these guys are, however.....

http://answers.yahoo.com/question/in...9051127AAh3oYT