Originally Posted by Topshot
What is the accuracy like at 1000 yards. Comparing the 1 : 11 twist to the 1 : 9 twist rifles?
If the 1 : 9 is more accurate than the 1 : 11 twist, it might be an indication that the 1 : 11 twist is slightly unstable and this is showing up as an aparent lower B.C.
Stability and drag can change trajectories so I'm not surprised that the BCs are different.
A faster twist does not allways mean better accuracy.The heaver bullet needs to rotate at
a optimum RPM and velocity will effect the required twist rate.
If you tried to shoot the lightest bullet (A 110gr)in a 1 in 9 it would probably over rotate the bullet and accuracy would fall off at the velocities that the RUM could push it.
If you only shoot the heaviest bullets in the RUM then a 1 in 9 will be ok, for all round bullet
weights the 1 in 10 is ideal and for the lightest/fastest bullets the 1 in 11 is the better choice
but the 1 in 11 somewhat limits you on bullet selection.
So Each twist rate has it's place and bullet weight and velocity will normally determine
the best twist for its use.
J E CUSTOM