Ace we have been over this one a couple times and Jim is correct for 250 yard shooting you definitely do NOT need a 1:7 twist or even a 1:8 as 200 to 250 yards is when most high B.C. bullets start to settle down. You only need to find the right bullet combo your barrel will like.69 grain to 75 grain is plenty to get to 250 yards. 900 yards may be a different storybut for 250 1:9 is good.