Originally Posted by ernierod
Thanks people for all the good advice. I will be shooting up to and occasionally 1,000 yds. I am thinking Remington 700. Will have a choice between SPS/26"/Heavy bbl-1:12 twist OR Rem 700SS Milspec 5R type rifling-24"-1:11.25 twist. I am aware that, most likely, the 1:10/1:11.25 twist will handle heavier bullets better than the 1:12 twist bbl but I am a beginner in LR shooting and don't really know how important heavier bullets are to the long range-(700+ yards) shooting in the accuracy department.Thanks for opinions. Erod
Note that heavier bullets in any cartridge make it harder to shoot accurately. This is why many top long range competitors quit using Sierra 190's in favor of the 155. With less recoil, the rifle moves less when the bullet's going down the barrel.
Optimum twist rates for Sierra's 30 caliber match bullets from a .308 are:
135 gr., 1:14
150 & 155 gr., 1:13
168 & 175 gr., 1:12
180 & 190 gr., 1:11
200 gr., 1:10
220 gr., 1:9
240 gr., 1:8
I wouldn't spin any bullet any faster than what stabilizes it. Any more will cause excessive jump of the muzzle axis as it exits the barrel. This is caused by the slight imbalance all bullets have and the centrifugal forces they have is quite a bit. Well, there may be 10 in a box of 100 that are perfectly balanced, but you'll need a tool to spin them a few dozen thousand RPM's plus a sensor to detect the unbalanced ones; all without damaging the bullet.
Friend of mine tested some 30 caliber match bullets for balance and kept those few that were perfect. Shot from a .308 Win. at 600 yards, most of the 10-shot groups were 1.25 inch and smaller, some around .75 inch.