308 barrel length

[nrakid88]

Um, have you ever seen the inside of a barrel? It's covered with copper, copper that rubbed off of the bullet as it went down the tube part. That my friend is FRICTION, and friction always slows things down. What they need to do is drill out the barrels a little bigger than the bullets so there would be less friction, then your 24" barrel would go faster.

You're welcome.

Funny, I have heard of tight bore barrels for reducing blow and increasing pressure/velocity.

[russ69]

I was told today at a shop that the ideal barrel length for a 308 is 18". Anything longer than that causes drag on the bullet slowing it down. Anyone ever hear that?

A standard velocity 22LR is done at 16 inches, but any centerfire will have increased velocity the longer the barrel gets until the barrel length is impractical.

With today's ammo I doubt barrel length is as important as it once was, especially at ranges under 600-700

Not sure what "today's ammo" is but there are no new developments that allow barrels to be shorter today than 40 years ago.

[Sunday]

More likely it would be between 20 and 24 inches for the best FPS.

[postal]

More likely it would be between 20 and 24 inches for the best FPS.

Most likely it would be between 33-40... since it's hard to find a barrel blank longer than 33-34..... not much testing has been done..

However those long barrels are impractical... so most people settle on 24-30.

I guarantee you a 26 has more vel than a 24, and a 30 has more vel than a 26 assuming quality barrels to begin with......

[FMJBT]

If you read this entire article... you will find it was about accuracy not velocity. Loads were tweaked for each barrel length, not for the highest possible velocity, but for group size. So just posting the velocity info is a little misleading, but not much.

Very good article.

I didn't see where any of the loads were tweaked for each barrel length, and they were about a 50/50 mix of factory loadings and handloads, so the factory loads velocity data should be good to go. I actually meant to link this article from Rifleshooter.com which does a better job of testing 308 velocity data from a 28" barrel cut down to 16.5" in 1" increments:

http://rifleshooter.com/2014/12/308-winchester-7-62x51mm-nato-barrel-length-versus-velocity-28-to-16-5/

Of the 4 loads tested in this article, the average loss in velocity from 28" down to 16.5" was 261 FPS with an average loss of 22.7 FPS lost per inch of barrel.

[sdnative13]

I'm no expert but maybe they were suggesting an 18" barrel for a semi-auto ar type platform. Like so many others said not good for bolt action

[JMP]

Um, have you ever seen the inside of a barrel? It's covered with copper, copper that rubbed off of the bullet as it went down the tube part. That my friend is FRICTION, and friction always slows things down. What they need to do is drill out the barrels a little bigger than the bullets so there would be less friction, then your 24" barrel would go faster.
You're welcome.

I shoot .224 in my 6mm, 6mm in my 6.5mm, 7mm in my .30 cal, etc. etc., I am one step ahead.

If you read this entire article... you will find it was about accuracy not velocity. Loads were tweaked for each barrel length, not for the highest possible velocity, but for group size. So just posting the velocity info is a little misleading, but not much.

Very good article.

http://www.thetruthaboutguns.com/201...-and-accuracy/

What they fail to mention is the contour of the barrel. If a very small cartridge like a .308, a thick contour can negate effects of whip.

Too many folks are looking at one-size fits all solutions.

And, WTF is all this 1:10" twist crap in a .308. 1:12" is what you want with a full size barrel.

[JMP]

Most likely it would be between 33-40... since it's hard to find a barrel blank longer than 33-34..... not much testing has been done.

Bartlein will spin you the blank, but I think they change $10 or $20 for each inch over 30".

[postal]

I'm no expert but maybe they were suggesting an 18" barrel for a semi-auto ar type platform. Like so many others said not good for bolt action

I have a 20" ar15 in 223 wylde since the 24" wasnt in stock.....

An AR has gas loss because the gas system, and have an even lower velocity than the same length barrel in a bolt gun....

[Victor Cachat]

I got a 20" and tacks live in fear.
(Provided someone better than me is shooting it.)

Seriously, it is the most accurate rifle I have next to my 24", bolt action 30-06.

[morthrane]

Just to play the devil's advocate...

For the average shooter, an 18" .308 barrel might actually be ideal. How many actually manage to shoot beyond 500 yards? An 18" should burn the powder load, so no ginormous fireball. A shorter barrel-- all else being equal and prior to considering wind-- is going to be more accurate than a longer barrel. You can have a heavier barrel that's not going to be as ungainly as a longer barrel of the same profile.

[FMJBT]

WTF is all this 1:10" twist crap in a .308. 1:12" is what you want with a full size barrel.

Maybe for little princess bullets. Real bullets do better with 1:10

[Terryw123]

308 barrel length

https://m.youtube.com/watch?v=kqTQyCgnO_Y

Here is an 18 1:10 shooting just fine

This one is even better. I'm not saying 18 is the way to go but, it works. Mine is 23" 1:11.25

https://m.youtube.com/watch?v=15qj032UJ1I

Sent from my iPhone using Tapatalk

[five.five-six]

But, you are right, an AR-10 pistol will probably go a mile, maybe two.

Sure, but you would need a primary arms red dot. None of those dinosaur scopes can see that far.

[five.five-six]

Maybe for little princess bullets. Real bullets do better with 1:10

Time in flight baby, time in flight.