A factory barrel will normally come with the 1-10.
If I was going a custom barrel and shooting 220s and under then I would go with a 1-11 or even 1-12.
Now I know a bunch will jump out and say no, but you will have less RPM stress on the bullets and especially in a magnum they will shoot great.
it was always thought that we had to have a 1-10. That might be correct if you are shooting a 220 at 2750 fps. Slower velocitiy requires a faster twist to stabilize.
Sierra recommends a 1-9 for example with their 240s. That is correct if you are shooting in the 2700 fps range. Up the velocity of over 2850 and the 1-10 shoots absolutely great.
JLK for exampe now recommends the 1-12 twist for their 210s and magnums.
Sierra recommends a 1-9 for example with their 240s. That is correct if you are shooting in the 2700 fps range. Up the velocity of over 2850 and the 1-10 shoots absolutely great. BH
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Until you get to about 1500 yards and they are all over the place,just ask BJ Bailey, as he tried them in his 10 twist Rum and they shot fine until he got to about 1500 yards
Accuracy and Stability requires twist and velocity. Lose one and you will lose the accuracy and stability.
Now other guys pushing 240s at 3000 and over have zero problems going past 1500 with accuracy. You will need a case that has enough capacity to push them with enough velocity to maintain stability. Ssame with any case/bullet combo, at some point they are unstable.