What would be the ideal twist rate for a 7-08 shooting mostly 140 gr bullets and the occasional 120 & 160 grainers?

I'll be trying to work up a load for the 120gr tsx also

I use 9 in all 7mms

8 in all 6.5s

My 7/08s shot 100s into groups at 200yds, as small as 1/2-5/8" for 3 shots. Same gun would put 150 SMK in one hole at 100 yds, 160s also did fine. That was a factory rifle btw.

Mine is a 1 in 9" and it will STACK 140s at 100 yds. It will shoot anything from 120-175 sub-MOA, but the 140s are the preferred fodder.

I have 9 twists in my 7-08 and my 7RM. I shoot bullets from 120 to 175 with no issues.

140's in the 7-08 and 175's in my 7RM give me .5 MOA.

sounds like 1:9 it tis....

hardin-I'm building a 7-08 right now, set up to shoot 140's. I asked here earlier and also asked the folks at Hart Barrels...and everyone says the same thing. 1 in 9 twist. I'm going 22"

What you got up your sleeve?

Nine or nothing

I'd use 1 in 10. The only reason to use a 1 in 9 in a 7mm is to shoot 175 grain bullets.

My Ackley is an 8 twist & loves, among other things, 120 TSX's.....

There was a good article in "Rifle Shooter" magazine on barrels and a formula for determining what twist for a particular bullet. When I've applied the formula for most 140's it comes out to 1:10.

You don't need a 1-9 twist in 7mm-08. I believe the traditional twist is 1-9.25 but my 7mm-08, Shilen barrel, had a 1-10 and it would shoot even 168 SMKs as well, if not better, than anything else. I shot mostly 110s and 154 Hornadys in it and the twist was quite perfect for that.

I had a 7 Mag built with a 1-11 twist to shoot the 120 and 140g bullets in. Accuracy was unreal from the very first time to the range till I sold the gun to a very good friend.

If you know for sure that you are going to shoot the lighter bullets, and never a 175g, then a 1-10 or a 1-11 is absolutely perfect. You may get by with a 1-12 for just the 120 and 140g Bullets.

With the slower twists, you will see less pressures at what you used to get at max charges with the 1-9 and higher velocities because you can load more powder. Many times there is an accuracy node at the upper limits of the powder charges that you just can't get to without ruining your brass and possibly not being able to get your bolt open.

Do some research on the proper twist rates for the length of bullets that you want to shoot...greenhill formula works good enough.

I wonder if those formulas consider what happens when a bullet hits game? Will the nose stay forward and penetrate in a straight line?

Seriously, for a hunting rifle, if one has a bullet 'just stabilized' is it not plausible that the bullet might yaw and tumble on impact?

The military inc. the Russians IIRC used 'just enough' twist so when impacting, bullets tumbled inside the foe, adding killing effect to FMJ type bullets indicated by the Hague Convention.

Just food for thought. I'd imagine a 10 would be fine for 140s in a 708, the 11 in the 7mag, remember has a higher mv/RPM than a 7/08 will have....

For the 7-08 with up to 160s go 1-9

If you are sure you will stay under 150grs then go 1-10.

BTDT with 1-9, 1-10 and 1-11.

MtnHtr

Mine is 1-9.5 and works for 120s thru 175s with great accuracy. Of course, it simply could be a matter of my superlative shooting skills! And now for the bridge I have for sale...

Actually I should have posted for up to 175s go 1-9

MtnHtr

I use 10 inch for shooting 150gr and lighter. That includes the longer 140gr TSX.

I use 9 inch if I'll be shooting VLD bullets over 150gr.

I have a 7-08AI with a 1:11 twist, stainless match grade 22" #2 Shilen, but I only shoot 140gr bullets in it. I believe the 7-08 was made for 140gr bullets. It is the cat's meow. You only need a faster twist if you shoot long bullets.

SST was right on the money, 1-11 is all you need for the 140 and perhaps the 150g.

The 1-9 is for the 175's.

I'm not sure that the 1-12.

The 130g Speer BT loaded with 42.0g of IMR 4895 drops deer in their tracks at 300 yards...combo is simply unreal accurate and deadly!

I prefer to have a bit of extra twist on hand rather than gearing it to a specific bullet/weight. Options are never a bad thing.

Resurrecting the thread, but 1:8.6 on a 7mm-08 is a VERY fast twist then yes? Ideal for heavy-gr bullets?

Yes.

But a 9 twist will stabilize a 160 AccuBomb. How much more of a bullet do you WANT in a 708?

9 twist for 120gr TTSX your wanting to run. That combo will kill any deer in GA(Lee county, Worth county, ect).

Wonder how I know this...

9 is great and 9.5 is one I will use on my next 7-08

I have both 9 and 10 twists. I use the 10 for rifles that will only see 120-140 with the occasional 150. I use a 9 inch for high BC bullets in the 150-168 range.

educate yourself on this subject.

http://www.bergerbullets.com/Products/Target%20Bullets.html

This is the LONG berger VLD Match bullets and their recommended twist rate, next go to the Hunting bullets. The Berger 140g Hunting VLD only needs a 1-11 twist. The Berger 140g Hunting bullet is longer than any other 140g hunting bullet on the market.

The reason for matching up proper twist rate is that many calibers love the accuracy at the top end of the pressure curve. If you slow down the twist rate, you conversely lower pressures slightly, and in many cases it will allow you to reach the high pressure accuracy "node" without ruining your brass or hard extraction issues.


On custom guns, I try and match the bullet that I am going to shoot with the twist rate with a minumum SAAMI spec reamer and usually achieve extreme accuracy at speeds that no one has heard of.

A 120g Barnes tripple shock will not stop when shooting through a deer length wise at 3000 fps, depending on the range. The Barnes tripple shock is about the same length as a 140g Nosler Accubond.

I built a 7-08 with a 1-10 twist. If I'm shooting over 150 grain bullet I will be using my 7saum or 7rem mag.

A 1-10" SAAMI 7-08 at 22",will bughole the 162A-Max from an OEM 2.815" COAL magbox.

That being said,I prefer a 1-9" in all my 7mm's...irregardless of case capacity and it's a foolish [bleep] notion to quip that skewing twist rates,will Magically add speeds that "noone has heard of". Keith is easily a consumate idiot and full of Imagination.

Curiously enough,I've a few 7mm's laying around...............

love the 'node' reference too... LOL

twist rate is lost in the background noise of factors affecting velocity. to get speeds no one has heard of before, you have to run pressures no one else will run. 'natural selection' at work.