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View Full Version : Best Weight Bullet For .308 1 in 12" Twist?


inGobwetrust
February 10, 2001, 11:34 PM
In general, what bullet weight works best in a 1 in 12" barrel?

Dave R
February 11, 2001, 12:33 AM
Shoot, now I'm gonna have to go measure the twist in my barrel...

My .308 is 1 in 12". My rifle (Rem 700) shoots tighter groups with 180gr. bullets. Next best groups with 165-168gr. Widest groups with 150gr.

From what I hear from folks who are supposed to be smarter than me, its not supposed to be that way. Theory is that tighter twists (1-10" for example) stabilize heavier bullets better than the slower twists. But that's what my gun does. Your mileage may vary.

Part of the fun is trying different loads to see what works best for you.

Paul B.
February 11, 2001, 01:10 AM
Dave R. I think your Remington barrel has a 1 in 10 inch twist. That's standard for Remingtons. It has been said that a 1 in 12 inch twist will not stabilze the heavier bullets. That's strange, as my Winchester model 70 in .308 with 1 in 12 inch twist will, repeat will stabilize heavy bullets, including the sierra 220 gr. round nose bullet. I even get a velocity of 2350 FPS. However, I doubt it would stabilize the 200 gr. spitzers and spitzer boattail. Groups with the Sierra run 3/8 inch average.
My favorite .308 load uses the Speer 165 gr. SPFB, but the rifle can and does shoot heavier bullets very well.
Paul B.

orsogato
February 11, 2001, 02:17 PM
What model Rem 700s do you have in .308

The ADL and ADL synthetic have 1 in 10 twists,

The 700 VLS, VS have 1/12 twists.

My lasts months issue of rifleman which I think the wife pitched I believ said that USMC m40 sniper rifles use 1/12 twists. I am pretty sure they use like a 155 grain or 168 grain match bullet for sniping.

1/12 should stabilize even the slightly heavier bullets

inGobwetrust
February 11, 2001, 03:50 PM
Orsogato, I just got a Rem. 700 LTR. The twist rate is 1 in 12 as far as I can tell. Was wondering if 150 gr. ballistic tips would work well with it. I also like the Federal Premium 165 gr. soft points.

By the way, I would think that the LTR would be an ideal vehicle for the .260 Remington, is this a project someone has tried?

Dave R
February 11, 2001, 06:03 PM
I have the ADL synthetic, so must be 1 in 10". Guess I should've used a ruler instead of eyeballing the rod as I pushed it through. Maybe that explains why it likes the 180gr.

Makes sense that the Varmit versions would have 1 in 12", tailored for lighter bullets.

k in AR
February 11, 2001, 06:26 PM
My 700 VLS, (1-12 26" barrel) prefers 165 - 168 gr bullets over all others tried. It shoots especially tight groups with Sierra Gameking & matchking bullets. Seems like the little additional length caused by the boat-tail design is a real plus over flat based 165gr bullets.

Just the Facts, Over the past 5 years, using Gameking bullets, I have recorded the following averages:
Shot from a bench rest, at 100 yards, 5 shot groups.
150gr right at 1 inch.
165gr 3/4 inch, * best 5 shot group recorded was a tight clover leaf at an honest 3/8 inch.
180gr 1 1/4 inch.
Hope this helps. k

path27
February 11, 2001, 09:01 PM
Factory Remington Model 700's chambered for .308 Win whether ADL, BDL, synthetic or wood use 1-12 twist. .300 Win Mags are chambered for 1-10. Marines M-40 used 1-11.2 twist. Most 1-12,s prefer 168's. But, as the other gentlemen said you mileage may vary.
Good shooting.

path27
February 11, 2001, 09:03 PM
The Marines new sniping round is M118LR. It uses a 175 gr. Sierra Match King bullet and Alliant Reloader 15 powder.

Tshoes
February 11, 2001, 09:15 PM
M40A1's use a 1-12 twist.........

M24 Army, 1-11.25 twist...........

1-12 will shoot anything thru 190's well, BTHP's......as long as you keep the vel up.( on the 180's-190's).

path27
February 12, 2001, 01:07 PM
Tshoes is right of course. Got my military sniper rifles confused. New M40A3 is also 1-12.

Spatula
February 12, 2001, 05:59 PM
For hunting, which I have little experience, you properly should refer to the recommondation from those loading manuals.
For target shooting: I know there is a formula that govorns the twist for given bullet length, but those are some real life experience that work.
Your factory Remington barrel has a 1:12 twist (better check it with a rod, it has been documented that Remington accidentally put a wrong barrel in some rifles).
You can give a try with Sierra's 155 Palma. Two of my shooting buddies have great result with those (under 1/2 inch 5 rds @200 yds.). Those are both factory 1:12 barrels.
Both of my 700's w/ 1:12 give very decent and consistant group w/ their 175 gr MK (<1/2 moa 5 rds, I like heavy bullet, but also a bit velocity at the same time). One foot note: sometimes the most accurate load is not the hottest load. It's a simple trade-off that you have to live with often. You can even try some 190 gr MK if you like. 1:12 is not too slow for 190 gr contrary to public belief. Some benchrest shooters in "Hunter class" use 1:13 or even 14 with 168 gr bullets @ ~ 2450 fps. We all know their goal is to shot very small group and that combination has worked well for many of them. Just give it a try. Don't get too suprised when one load shots great at one distance but terrible at the others.
Good luck