Barrel length for 308

[KSB209]

Planning a build and looking for input. Is there really any noticeable difference in a 22" vs 24" barrel for a 308? Was planning on a 24" barrel but now that I think I want to add a break I was wondering if I will loss much velocity if I went 22". This is for a hunting rifle with shots kept under 400 yards

 

[Jud96]

There will realistically only be about a 40-50fps change with the same exact load. If you're really worried about it, then do a 23" barrel.

 

[Steves1911]

I run 20" on all my 308s its a pretty efficient cartridge. Pushing 178gr pills around 2550 + or - about 30fps depending on which gun.

 

[KSB209]

I have one with a 20" also. Just want something a little long this time. More for long range shooting targets but this will also be my primary CA hunting rifle.

 

[whhood]

Definitely don't need 22-24" to only go 400. My longest 308 is 18" and it has plenty at 400. I also wouldn't put a brake on a hunting rifle unless it's a lightweight magnum or a suppressor mount. I get 2650 at the muzzle with my 165s.

 

[Nomosendero]

I run 20" on all my 308s its a pretty efficient cartridge. Pushing 178gr pills around 2550 + or - about 30fps depending on which gun.

Yes, very efficient.
Going from 24" to 22" means very little with a 308. I have a Rem 700 5R Mil-Spec, it comes with a 24", it shoots so good I will leave it alone but I would rather have it in 22.
I also have a RAR I had cut down to 18.5", no problem with 400 yds.
I think a good all round length if I had one 308 would be 20".
Here is a good article with 308 vel. with different length barrels. https://www.6mmbr.com/308Win.html look at bottom of article.
And another: https://rifleshooter.com/2014/12/30...ato-barrel-length-versus-velocity-28-to-16-5/

 

[Bucklowery]

Heavy 20 on mine and it is wonderful. 1:10 the 168g pills are the ticket

Thanks

Buck

 

[Buster Hemlock]

I have an 18" 308 and taken it to 1300 yds. on targets with 175 SMK's and 215 Berger's, well through transonic and into subsonic. For max of 400 yards as you stated in my opinion 18" is more than enough with a 168+ grain projectile on deer and smaller game.

 

[Steves1911]

If your only reaching 400yds I do that with a 16" ar10 no problem. It's my primary "woods" gun for whitetail. Ive run the 20" guns out to 1k fairly often.

 

[KSB209]

Yes, very efficient.
Going from 24" to 22" means very little with a 308. I have a Rem 700 5R Mil-Spec, it comes with a 24", it shoots so good I will leave it alone but I would rather have it in 22.
I also have a RAR I had cut down to 18.5", no problem with 400 yds.
I think a good all round length if I had one 308 would be 20".
Here is a good article with 308 vel. with different length barrels. https://www.6mmbr.com/308Win.html look at bottom of article.
And another: https://rifleshooter.com/2014/12/30...ato-barrel-length-versus-velocity-28-to-16-5/

Thanks for the info and articles. Very informative. I was originally planning a 24" barrel but looks like 22" might be the sweet spot in the tests. A little gained velocity going longer but at some point it will start diminishing

my main goal is trying to keep the 150-165 grain bullets around 1900+ FPS at 400 yards so they can do their job. Because it is a CA rifle I need to use non lead projectiles. Ideally I would like 2000 fps at 400 yards but I'm not sure factory ammo can do that in a 308. Eventually when I start hand loading I might (maybe) be able to accomplish 2000 fps @ 400 yards but from what I have been reading but that is a BIG maybe. Will probably have to move up to the 300wm for velocities like that

 

[whhood]

This is a factory sig sauer load out of my 18" barrel.

 

[jpfrog]

Thanks for the info and articles. Very informative. I was originally planning a 24" barrel but looks like 22" might be the sweet spot in the tests. A little gained velocity going longer but at some point it will start diminishing

my main goal is trying to keep the 150-165 grain bullets around 1900+ FPS at 400 yards so they can do their job. Because it is a CA rifle I need to use non lead projectiles. Ideally I would like 2000 fps at 400 yards but I'm not sure factory ammo can do that in a 308. Eventually when I start hand loading I might (maybe) be able to accomplish 2000 fps @ 400 yards but from what I have been reading but that is a BIG maybe. Will probably have to move up to the 300wm for velocities like that

Get a 9 twist and run the 181 hammer hunters from Steve. Or the lighter hammers so you can keep your velocities up.

my 2 cents, but if you already have a 20, build a 24. 22 isn't going to do much over your 20. I have a 20 as well but wanted to run longer monos at a faster twist so I built a 24- and I wanted it to be light but big enough for a suppressor if I wanted so I went with a carbon barrel

 

[TheLongRanger83702]

Thanks for the info and articles. Very informative. I was originally planning a 24" barrel but looks like 22" might be the sweet spot in the tests. A little gained velocity going longer but at some point it will start diminishing

my main goal is trying to keep the 150-165 grain bullets around 1900+ FPS at 400 yards so they can do their job. Because it is a CA rifle I need to use non lead projectiles. Ideally I would like 2000 fps at 400 yards but I'm not sure factory ammo can do that in a 308. Eventually when I start hand loading I might (maybe) be able to accomplish 2000 fps @ 400 yards but from what I have been reading but that is a BIG maybe. Will probably have to move up to the 300wm for velocities like that

Guess what weight bullets you'll be shooting might come into play. Lighter bullets/shorter barrel. Heavier/longer.

 

[Savage 12BVSS]

As others have stated the 2" difference is minimal in the bigger picture and you should not worry a lot about it. I use a 20" and 24" and feel neither are handicapped.