03-17-2011, 08:13 PM
cmdc Wrote:How well does the 1:9 twist stabilize the heavier bullets?
CM:
Not well. For a 1/9 twist you are pretty safe with bullets as long as the 123 Sierra / Lapua. I would think something as long as a 130 or particularly a 140 are too long for a 9 twist but are ideal for a 8 twist.
Don't worry about it. When guys start blasting 140's, the bullet takes up so much cartridge space that its velocities are pretty dismal. When using an AR-15 frame and magazine, the Grendel cartridge is pretty much maxed out in terms of efficiency with bullets that by default are the 120's. I contend that probably the best bullet weight in terms of potential velocity from a Grendel case is 110 or 115 grains but you won't find these commercially made.
LR1955