help needed for twist rate on new custom 308

[hkfan45]

So after going back and forth on the merits of the 260 vs 308, I've changed my mind and have decided on the 308. Driving my decision was a lack of 260 factor match ammo. Now, I need help decided on a twist rate for the 308. This rifle will be used primarily between 100-600 yards. Field work (can't be more descriptive due to nature of position) and casual target practice will be its primary uses. F class could also be a possibility down the line. Rifle is 24" built on an Eliseo stock.

The consensus seems to be that 155 and 175gr are the grain of choice. Should I choose a twist rate that is a compromise between these two rounds, or choose a bullet and build the rifle around this?

Thanks.

 

[tylerw02]

Go with 1:10" to maintain the option to go heavier if you decide to later on. 1:10" does perfectly fine with 155s and 175s and gives you the ability to go heavier should you decide at a later date. I've also found that the 1:10" is enough for 180 SPs subsonic.

 

[hkfan45]

Which brings up the question, should I even be concerned with 155s, given my intended max range of 600, maybe 800 yards?

 

[tylerw02]

If you're going to shoot F-Class, YES! I'd shoot Lapua 155s and go with a long barrel. To be competitive, you're going to want to build the gun around that competition. I've shot a few multi-range F matches and shot a kind of odd match this past weekend with a "tactical" rig and managed 2nd with a 389-9x, so it can be done...but a real F-Class rig is going to make things much easier.

But for 600-800 yards, you'll be fine with 1:10", 1:11.25", and 1:12". I'd probably only consider heavier if I wanted to extend the range.

 

[popeye089]

If its a custom build have it chambered for your specific bullet you're running

 

[pinkhair]

I used 1:11.25 on my .308 in a 24" tube and it shot everything from 155gr scenars up to 178 amax equally well.

 

[bjay]

If you want to babysit 155s id say 28-30" 1:12 twist but if you wanna play around 155-175 1:11.25 id say is perfect 20-26" barel will get u even to 1k...if your chasing f class where BC is almost when competiton comes then go with 1:10

 

[thrusty]

Many people have told me that the 1:11.25" works great for both the 155 scenars and the 175smks. I have also seen it first hand in a couple matches.
When I do a 308 build, it will be this twist...

My 1:10" AAC-SD hates the 155 scenars with a passion. That's not to say that twist wouldn't work for you though...just putting it out there.

 

[Sniper260]

I would think about what you are trying to do with the rifle first. What is your main goal for the rifle to do. Then pick you bullet based around that. Then get the twist rate that is best for the bullet you choose. When I build my 308, I know I want to shoot the heaviest bullet I can from sierra, or berger... Thats tell me I'm pretty set on a 1:10 twist for my own personal build. It all just depends what your final goal is your trying to achieve.

 

[gstaylorg]

Unless you plan on shooting heavies (200 gr and up) an 11-twist will do everything you need.

 

[Boogaloo]

I have 2 custom .308's both with 1:10 24" barrels. One is a Kreiger, the other a Bartlein. BOTH rigs shoot the 155's through 178's exceptionally well. I have not shot anything lighter or heavier than that so that is where my experience ends... Both my rigs are sweet all the way out to 900 yards so far.

 

[Highflyer]

My rifle came with a 1 in 10. Test target 10 shots one ragged hole, 100 yds with match 175gr bullets.

 

[JGorski]

Judging from the recent lot of 178HPBTs, id have to say 10 twist, my 12 twist SPSS shoots them in a diagonal pattern, my Classic stocked, S/S barreled Rem, 10 twist shoots them much better. Here it is with my 708 on top.
<a href="http://s1113.photobucket.com/user/JGorski80/media/IMG_0143.jpg.html" target="_blank"><img src="http://i1113.photobucket.com/albums/k513/JGorski80/IMG_0143.jpg" border="0" alt=" photo IMG_0143.jpg"/></a>