I am currently building me a precision AR as a range toy/varmint gun. I do plan on doing a load development for it when I finally get it built but I need help deciding on what type of barrel I am going to get. I have decided on the Shilen barrel chambered in 223 wylde in 20 inch length. The question is that I have not found enough information on should I go with the 6 groove or the 4 ratchet of the barrel. Price is not an issue as they are both the same cost but I know that I am only going to get one barrel so any information I could get would be helpful. My Google fu seems to be weak in this as I have not found any real information of the pros and cons of either rifling grooves.