308 win barrel length and twist rate?

[SamuelBerryhill308]

I'm looking at re barreling a rifle I have and want to stay with 308 win. The barrel on it now is 20 inch's 1/12 twist (from what I can tell) I'm wanting to go with a little longer barrel and fast twist rate. I've been looking at outlier barrels as they have a sale on their prefit barrels. The only 308 caliber barrels they offer is 1/8 twist from 18 to 26 inch's. I was thinking of getting a 22 inch barrel with the 1/8 twist rate would I be hurting my self in any way by doing so or should I go back with 20 inch or go longer than 22 inches? Also would 1/8 twist be to fast for lighter bullets? I've heard of over twisting bullets but I've never experienced this or what can happen by doing so? Any help is greatly appreciated thanks. God bless

 

[Nomad458]

Best option is use a calculator for yltwist rate for what you want the rifle to do with what bullet selection. Something like this, there's others out there too if you search the web

JBM - Calculations - Stability

www.jbmballistics.com

 

[SamuelBerryhill308]

Best option is use a calculator for yltwist rate for what you want the rifle to do with what bullet selection. Something like this, there's others out there too if you search the web

JBM - Calculations - Stability

www.jbmballistics.com

I have looked into this. I'm wanting to shoot 210 vlds to 168 amaxs for plinking or hunting and I also want to run the 150 to 168 coppers for hunting.bum mostly worried about having to fast of twist rate for like 110 to 150 grain bullets for ground hog and varmint shooting if need be. What happens when a bullet is shot in to fast of twist rate and does it effect accuracy?

 

[Mark37082]

It would seem to me a 1/8 would be a little too fast for a 308win. If you like to shoot varmint cup and core bullets, I would be concerned about the bullet coming apart before the target. I have no personal experience with this fast of twist in a 308win, so take my comment as just a gut feeling.

 

[Mike D Texas]

1:8 twist will work fine for the bullet ranges you listed.

.308 would have a hard time getting enough velocity to overspin them.

 

[MagnumManiac]

Optimum twist for 308 is right at 1:12", 10" is fast already in 30 cal.
When I shot PALMA, we used 4 groove 1:13" twist for 155g PALMA bullet and Varget, rules dictated 155g only.
I would be perfectly happy running a 12" twist in a 308, however, what bullet weight are you wanting to run, if 200g+, go 10".
I have zero preference for barrel length.

Cheers.

 

[C-130 Dude]

I have looked into this. I'm wanting to shoot 210 vlds to 168 amaxs for plinking or hunting and I also want to run the 150 to 168 coppers for hunting.bum mostly worried about having to fast of twist rate for like 110 to 150 grain bullets for ground hog and varmint shooting if need be. What happens when a bullet is shot in to fast of twist rate and does it effect accuracy?

In my experience, a 1:10 will handle most all from 130-185. My bolt guns like 1:10 with 150-175. And my AR guns like 1:11 or 1:12 with 110-135. I've been playing around with these twist rates in all my .308win for 50 years +. If your wanting a bit more weight, the 190-220 could use a bit more twist; 1:9 or a 1:8 will be needed to stabilize these nicely. But if you go with the fast twist such as the 1:8, you will limit yourself using 110 bullets. You may find them over stabilized. I have destroyed a few 110 bullets with the 1:8 many years ago using max pressure loads. If your very careful, you can push a 110 to around 3100. Some folks may have done more. But i dont know about the results. Mine weren't great at all. Thats why i dont try that anymore. Your milage may vary. Whatever you do, be careful. We dont want to read about any incidents. Unfortunately, we can't have it all. Fast twist for heavies, and slower for lighter bullets is the general rule of thumb. It's always a compromise. Some of the bullet manufacturers state the reccomended twist rates for their products. This is always a good starting point. Consider looking at a twist rate calculator like another member mentioned. As for barrel length, it really depends on you. If you intend to use a can, you may want a shorter barrel, say around a 20-22 inch. For max velo, a 24-28 inch will do the trick. Decisions, decisions. Stay safe and have fun.

 

[Rflshootr]

I have a 12 twist 308. It won't shoot anything heavier than a 168. If you want to go heavier that a 168, then get a 10 twist. That would handle up to a 230 grain Berger, which in my experience is way too much bullet for a 308, unless you like really slow bullets with a big trajectory. My experience is that it is much harder to tune light bullets in a fast twist if you can ever get them to shoot accurately.
I looked at their site and I see why you're looking at that barrel. Price! I don't even see a listing for what profile those barrels are. I'd be leery. My gut says go with a Shilen 10 or 12 twist depending on the bullet weight and cry once.

 

[osok-1k]

The M24 is 1-11.27, I talked with Mike Rock about why some years ago when I was probing the same question about barrel length and twist. He said that 11.27 was more for fun to make people scratch their heads but that it was an optimum twist for the 175gr M118 round. He also said that "22 is perfect for 308 in that it efficiently burns the powder and has little muzzle flash. Desired in a combat environment. My 700 PSS is 1-12 and cur to 22" and shoots 175 SMK at 1/2" at 200. Remington 5R rifles are 11.25 twist and 24" barrel. They shoot well. The only reason I would use a fast twist in 308 would be for subsonic heavy bullets. I've not shot heavier than 178 in any of my 308 rifles so I can't personally attest. My Tikka hunting 308 is 1-11 and 22.3 I believe. 308 is capable of shooting light bullets pretty fast and I think the risk of separation is real. Mike Rock owns Rock Creek barrels and was instrumental in developing the M24 rifle at Aberdeen Proving Ground for the Army. Just in case you never heard of him.

 

[Rflshootr]

The M24 is 1-11.27, I talked with Mike Rock about why some years ago when I was probing the same question about barrel length and twist. He said that 11.27 was more for fun to make people scratch their heads but that it was an optimum twist for the 175gr M118 round. He also said that "22 is perfect for 308 in that it efficiently burns the powder and has little muzzle flash. Desired in a combat environment. My 700 PSS is 1-12 and cur to 22" and shoots 175 SMK at 1/2" at 200. Remington 5R rifles are 11.25 twist and 24" barrel. They shoot well. The only reason I would use a fast twist in 308 would be for subsonic heavy bullets. I've not shot heavier than 178 in any of my 308 rifles so I can't personally attest. My Tikka hunting 308 is 1-11 and 22.3 I believe. 308 is capable of shooting light bullets pretty fast and I think the risk of separation is real. Mike Rock owns Rock Creek barrels and was instrumental in developing the M24 rifle at Aberdeen Proving Ground for the Army. Just in case you never heard of him.

Current Remington 700 5R's are a 1:10 twist. I have one.

Model 700 | Remington

 

[Horse1]

.5 + BC 155's are pretty hard to beat out of a 308. It is IMO the "sweet-spot" of BC and velocity. When you go heavier, it's difficult for BC to make up for the velocity you lose.

 

[Josh06]

I'm looking at re barreling a rifle I have and want to stay with 308 win. The barrel on it now is 20 inch's 1/12 twist (from what I can tell) I'm wanting to go with a little longer barrel and fast twist rate. I've been looking at outlier barrels as they have a sale on their prefit barrels. The only 308 caliber barrels they offer is 1/8 twist from 18 to 26 inch's. I was thinking of getting a 22 inch barrel with the 1/8 twist rate would I be hurting my self in any way by doing so or should I go back with 20 inch or go longer than 22 inches? Also would 1/8 twist be to fast for lighter bullets? I've heard of over twisting bullets but I've never experienced this or what can happen by doing so? Any help is greatly appreciated thanks. God bless

I'd never heard of this company but they are close to me in Texas and with the Father's Day sale it was too good to pass up so I just ordered a 18" 308. I'll be shooting 168 LRAB out of it suppressed. I had been shopping for a Savage 308 barrel, thanks for posting about them!

 

[Tiny Tim]

I went with a 1:10 twist at 20 inches. That was my compromise between short enough for a suppressor and not giving up much on performance without. I think 8 twist is way to much for the 308 Winchester. 9 twist in my 300 RUM will stabilize the 230 Berger down to 0 F at sea level for reference.

I understand the bargain aspect, but its not a bargain if it doesn't produce the results your after. Only you can decide.

 

[tx338]

1:10 twist on a 20" bbl 308 here.
I shoot 175-185gr bullets, my K&P barrel shoots them well.

If you intend to shoot 168's and lighter bullets, slower twist is likely better.