Well, the original specs for the .308 Win. (pre-64 M70 FW rifle) called for 1/12" twist. This is good for all bullets, up to the 200 grain spitzer flatbase Win. used to load. But personally, I preferred a 1/10" so I could use 220-grain bullets too.
In an old Gun Digest, the author of the article worked that question out. He shot all weights of bullets from 110 to 220 in duplicate rifles to test for "what was the best twist." To make it short, he concluded 1-12 was the best, but in the weights you asked about it was nip and tuck as to what was the best. Lighter, the 1-12 won. Only in 220gr. bullets did the 1-10 come out the clear winner. I built a Model 70 pre '64 to duplicate the Marine Corps sniper riles of Korean war/early VN, complete with the proper Lyman scope. I had a Hart barrel put on it and really worked myself into a lather as to what rate of twist. I went with the 1-12 and it shoots sub minute of angle with Sierra 190 Match Kings. If I had it to do over, I'd still stay with the 1-12, but had I gone the other way with the 1-10, then I just wouldn't shoot anything lighter than 125 gr. bullets. Don't screw yourself into the ground over this, just remember if you want to go heavier than 200 gr. bullets, 1-10. If you want to shoot 110 gr. bullets, go with the 1-12. Anything in between, either is a great choice. IMHO.
Posts: 426 | Location: Nevada | Registered: 14 July 2003
The factory standard is 12" for the .308 Win. I have not needed a faster twist in any of my .308s, but I stick with 180 grain premium bullets.
jim
Actually, I've got a Remington Stainless sporter barrel which replaced the Varmint barrel, along with a classic stock on my Varmint Special 308 that's 1 in 10", but yes, most 308 barrels are a 12 twist. Side note, it's better to overstabilize a bullet than understabilize it, I know, DUH, Jay
Posts: 1745 | Location: WI. | Registered: 19 May 2003
My .308 Win target rifles are 1-10" rate; my Tikka and Sako rifles have a 1-11" rate. I have not had any stability problems with bullet weights up to 200 grains. Have never gone higher in the .308 Win.
Posts: 262 | Location: PA & VA, USA | Registered: 26 June 2003
Lonnie, I would suggest consulting with your riflesmith on what he would recommend based on the bullet you plan to shoot with the rifle. For a hunting rifle I'd opt for the 1-12. For a LR/F-class/Tactical style rifle, 1-11" gets the nod.
