just my 2 cents worth here. My 9 twist will not shoot anything below 69 grains.I tried the 50-55 etc and anything past 100 yards were not worth a darn.Now the 69 sierras were minute of angle out to 300 yards..I have a new 7 twist barrel now,but haven't done much testing with that one yet..Let us know how you made out with them..