i am finally getting a new barrel from either Shilen or Bartlein Barrels, i have a Remington 700 30-06 and now it comes to the twist and grain size and my brain hurts from so much reading and thinking. I will be hunting whitetail and hogs with it along with a lot of range. 150 grain are fast but little weight but the big 200-220 have weight but no speed. I don't know what the size will do to the range though, but i don't plan on shooting much over 600-700 yds because i have no place that is that wide open here. what size would yall suggest and twist?