I have a 16.5" Fluted Green Mountain on my gun and I have only shot with it once, I can see that it has AMAZING accuracy potential. If you are willing to spend the money, an Rimfire Technologies Quantum barrel are some of the best barrels out there. You would probably have to go to the states to get one, but they are a light THM barrel. I have also heard good things overall with the Butler Creek 20" Fluted or Non fluted STEEL barrels....stay away from their carbon fibre....unless you want the equivalent of a 10/22 shotgun