I'm considering an FN AR. (yes, I know it's an ugly gun) But here's the dilemma. Which barrel to go with? There is a light and a heavy version. Here is a link if you want to look at it: http://www.fnhusa.com/le/products/firearms/family.asp?fid=FNF049&gid=FNG022 The most realistic use will be target practice. I would like to learn to shoot long distance but have little experience. What are the advantages of the heavy barrel? thanks for your input.