03-28-2023, 04:38 PM
When Bill Alexander did the initial testing with different barrel lengths for 6.5 Grendel, he found that 1/8.75 and 1/9 stabilized the LR bullets fine from 20 and longer barrels.
For 18 and shorter, he went with 1/7.5 twist.
I recall that my first 16 AA barrel was the tight 1/7.5 twist, and was very predictable at 1200yds with 123gr A-MAX.
My 17.6 Lilja with 1/8 twist is predictable out to 1000yds at 6600ft elevation/23.4 hg, but Im not sure what it does after that. Im trying to recall if Ive stretched it out past 1000yds and am drawing a blank.
For 18 and shorter, he went with 1/7.5 twist.
I recall that my first 16 AA barrel was the tight 1/7.5 twist, and was very predictable at 1200yds with 123gr A-MAX.
My 17.6 Lilja with 1/8 twist is predictable out to 1000yds at 6600ft elevation/23.4 hg, but Im not sure what it does after that. Im trying to recall if Ive stretched it out past 1000yds and am drawing a blank.
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com