You should notice spin drift at all times when shooting long range. If you have a 8 twist, you'll get more drift than with a 9 twist. I have a target rifle which is a 223 with 6.5 twist barrel for shooting 90 grain vlds. On the first string in the morning when it's dead calm I'm 6" right with my 2840fps load and 3.5" right with the milder 2650 load at 600 yards.
