Gotcha!!! I see you hiding behind those trees at 1800 yards with my bigeyes. (Just kidding). Anyway, the question is the number of grooves. Does it mean it depends on which caliber and the bullet weight? or just your preference? I think 3 grooves is a good investment. "Less is better" because it will give you less error? If you create 6 grooves, you try to do your best to make it all even. (That would not be a problem for button tool). Six grooves will give more friction on the bullet, correct? What do you recommend for 300gr. Matchking?