Best all round .308 barrel length?

[Chanonry]

I'm shooting a 20" and a 26" 308.

This is all just conversation/opinion, but I'd suggest a 20-24" for all around use, depending on your preferences.

Longer or shorter lengths than that, are getting into niche-rifle territory, in my humble opinion.

Exactly. No basis for a decision on this thread other than popularity.

I tend to agree with the view that if you are beyond 800 a lot then a 6.5 is probably a better option. Other than that it depends on use and hit probability. 20" is easier to get out the truck door but loses some velocity. 24" is a bit more wieldy (but so what) but has that extra 100fps so a bit less drop and windage and more energy. Is the hit probability at say 800 much different? Probably not. Does the marginally better ballistics make much difference, possibly if you are target shooting or are focussed on energy on target.

Everyone is jumping on the short rifle trend but if you look at what the comp shooters use they have longer rather than short barrels (and 6mm or 6.5's). There is a reason. Hit probability

 

[MoBoost]

Too many opinions and not enough science on the topic imo. Has no one done a controlled test with posted results?

Controlled tests happen every week - equipment and theory is tested at matches!

(note: the rest of the post is not directed at anyone in specific)

Try to run-and-gun with a 30-inch 18lb gun and you won't be able to physically get the rifle into a lot of shooting positions at all.

Bring an 18-incher to a F-Class match and get ass handed by the 30s. I am sure there will be a story of "hitting the Xs" and "did good for what it is" - but the whooping is inevitable.

For some reason F-class shooters are more reasonable about limitations of their equipment than the tactical shooters.
After seeing a lot of "handy" 22" rifles with 8" suppressor, I really have to wonder about the logic there as well.

20" will be fantastic for short range work, hitting steel out there on good days, and practice. Develop skill and equipment from there. Unfortunatelly 308 is a jack of all trades master of none.

 

[softcock]

Wow, this Thread discussion been going on for a while .

( just my opinion ) . I have had 24" and 26"
but over 4 thousand rounds out a 22" .308 win. Barrel, and I am still in love with it .
Have a exact new blank sitting in corner and will do it over again @ 22" . Easy to throw it around and handling . While not to long with a Can on Muz. . Still will drop them in @ 1025 to 1050 on steel pretty respectable too .
.

 

[ashiha]

Controlled tests happen every week - equipment and theory is tested at matches!

(note: the rest of the post is not directed at anyone in specific)

Try to run-and-gun with a 30-inch 18lb gun and you won't be able to physically get the rifle into a lot of shooting positions at all.

Bring an 18-incher to a F-Class match and get ass handed by the 30s. I am sure there will be a story of "hitting the Xs" and "did good for what it is" - but the whooping is inevitable.

For some reason F-class shooters are more reasonable about limitations of their equipment than the tactical shooters.
After seeing a lot of "handy" 22" rifles with 8" suppressor, I really have to wonder about the logic there as well.

20" will be fantastic for short range work, hitting steel out there on good days, and practice. Develop skill and equipment from there. Unfortunatelly 308 is a jack of all trades master of none.

Yes, but a lot of this real world testing conflicts with itself. An example would be the way that Dallas SWAT article mentions how the powder had completely burned with a 20" barrel, but then why would benchrest shooters use 30"? The one article from "The Truth About Guns" was pleasant, but many holes were left leaving too much room for error (factory ammo with unknown SDs, chopping off 8" after the first test, etc.)

I agree about the 308 being a master of none though. I think it might be phased out in the future because of this.

 

[MoBoost]

An example would be the way that Dallas SWAT article mentions how the powder had completely burned with a 20" barrel

Power might be burnt, but the pressure is still applied to accelerate the bullet; there is no "conflict" that a 30" barrel is significantly faster than a 20" barrel.

In laymen terms - that 10" longer barrel gets you 150-200 yards "closer" to the target. That difference might not matter when your bullet drop is 10 inches every 100 yards at close ranges; but out there, where the bullet drops 10" every 10 yards - that's a HUGE difference. At 950 yards bullet launched 300fps faster will have DOUBLE the certainty of a hit - for both wind and distance uncertainty. As I said HUGE difference.

 

[calshipbuilder]

just as one data point, my 24" Remington gets the same velocity as my buddy's 20" savage using M118lr. My next 308 will be wearing a 16" barrel

 

[clj94104]

Power might be burnt, but the pressure is still applied to accelerate the bullet; there is no "conflict" that a 30" barrel is significantly faster than a 20" barrel.

In laymen terms - that 10" longer barrel gets you 150-200 yards "closer" to the target. That difference might not matter when your bullet drop is 10 inches every 100 yards at close ranges; but out there, where the bullet drops 10" every 10 yards - that's a HUGE difference. At 950 yards bullet launched 300fps faster will have DOUBLE the certainty of a hit - for both wind and distance uncertainty. As I said HUGE difference.

Well said.

 

[WhiskeyBravo]

I prefer 20". But that's what I've come to have peace with...
Then again, with a 30" barrel if you miss you can just beat the target to death with the muzzle.

 

[jashmore1234]

I run 20" and 23". The 20" is 1/10 Twist and throws 185gr Juggernauts in the 10 ring at 1000 and 175 gr. SMK's at .3 MOA at 100. I'm still breaking in the 23", but it throws 175 gr. SMK's at .2 MOA at 100.

Here's the take away. If it is built right, pick a length you like and work up a load. It will shoot better than you.

 

[csireeves]

I saw it mentioned a few times that the twist rate and length matter, but no one gave any examples using both. To piggy back on this thread, I have a 700 SPS Synthetic Varmint 26" barrel with a 1:12 twist. The range I have access to goes out to 300 yards (soon to be 400 yards) and occasionally I will have access out to 1000 yards. I am wanting to cut the barrel down and have it threaded for use with a suppressor. How will a 1:12 twist rate 26" barrel be effected if it was cut down to 22" or 24"? It will eventually be rebarrelled, but I figured I would work to wear out the stock barrel before having it changed.

 

[ashiha]

Power might be burnt, but the pressure is still applied to accelerate the bullet; there is no "conflict" that a 30" barrel is significantly faster than a 20" barrel.

In laymen terms - that 10" longer barrel gets you 150-200 yards "closer" to the target. That difference might not matter when your bullet drop is 10 inches every 100 yards at close ranges; but out there, where the bullet drops 10" every 10 yards - that's a HUGE difference. At 950 yards bullet launched 300fps faster will have DOUBLE the certainty of a hit - for both wind and distance uncertainty. As I said HUGE difference.

Since there is no easy way to measure if the powder is actually burnt or not, I took what was written as a way of saying that the MV did not increase for lengths above 20". I already know that higher velocities will help things out.

 

[Greg Langelius *]

There's a lot more to velocity than just barrel length. Tighter/looser bore diameters, bore finish/friction, chamber reamer configuration, and fouling state all contribute even without factoring in ammunition-related issues like projectile bearing surface length and bullet diameter. It doesn't take much variance in these factors and those variances are very common, but their impact can be pretty startling.

Laying out a clean bed sheet in front of the muzzle will catch unburned powder granules.

Loads configured for shorter barrels often use propellants with faster burn rates, like the 4198's; while loads configured for longer barrels (and heavier projectiles) will often favor slower propellants, like the 4831's. So it's less a matter of getting the charge to burn in the shorter barrel, but more of being able to take full advantage of the longer barrel's capacity to run a heavier projectile and fully consume a larger charge of a slower powder. Running identical loads in widely differing lengths simply fails to take full advantage of either length's optimal advantages.

I'm not trying to chastise anyone here, my main intent is to share knowledge, and provoke critical thought.

Greg

 

[surffly]

I went with a 20" AAC-SD Remington 700
Figured it gave me a nice balance.
Shoots great.

 

[Jedi]

Most here mention fps advantage of longer barrels, while true to an extent a savvy reloader can negate this issue.
I run a 20" x47 lapua, using modern high energy powders this lil rig stays sonic out to 1400yds with 123gr bullets
Thats 3023fps, why then would i run a longer barrel?
Work smarter, Not harder

 

[lifebreath]

There's a lot more to velocity than just barrel length. Tighter/looser bore diameters, bore finish/friction, chamber reamer configuration, and fouling state all contribute even without factoring in ammunition-related issues like projectile bearing surface length and bullet diameter. It doesn't take much variance in these factors and those variances are very common, but their impact can be pretty startling.

Laying out a clean bed sheet in front of the muzzle will catch unburned powder granules.

Loads configured for shorter barrels often use propellants with faster burn rates, like the 4198's; while loads configured for longer barrels (and heavier projectiles) will often favor slower propellants, like the 4831's. So it's less a matter of getting the charge to burn in the shorter barrel, but more of being able to take full advantage of the longer barrel's capacity to run a heavier projectile and fully consume a larger charge of a slower powder. Running identical loads in widely differing lengths simply fails to take full advantage of either length's optimal advantages.

I'm not trying to chastise anyone here, my main intent is to share knowledge, and provoke critical thought.

Greg

This.

 

[MoBoost]

I run a 20" x47 lapua, using modern high energy powders this lil rig stays sonic out to 1400yds with 123gr bullets
Thats 3023fps, why then would i run a longer barrel?
Work smarter, Not harder

If your goal is to run 123s @ 3000 - then you wouldn't need to run a longer barrel. If you want to be competitive in F-Open - you'll need to push 140s at the same speed - and that will require a longer barrel.

 

[Jedi]

If you want to be competive in f open you dont shoot a 6.5 period

The guys that take home the $$ mostly run 7mm now

 

[Dallas4rceMarine]

oh yay, we finally transitioned from 20" 24" or 26" .308 barrel (as the OP asked) to which 6.5mm bullets are better and then compared them to the 7mm. Which barrel lengths GAP offers, which length SWAT uses, and who knows what else I skimmed over.

get a 20" .308 and when your ready to go past 800yds, get a better caliber!



I'll take the brunette for $1,000 Alex!

 

[lifebreath]

Best all round .308 barrel length?

22.731415926"

 

[clj94104]

24" ftw

 

[Bradaus]

22.731415926"

You mean 21 & 3/4"

Secrets of the Houston Warehouse







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[Quickdraw Outlaw]

My GAP TR in 22" is very handy.

 

[lifebreath]

You mean 21 & 3/4

Oh no. I mean exactly 22.731415926"

You see, since 22/7 was the ancient closest approximation of Pi and 3.1415926 is Pi out to 7 decimals, if you construct the barrel length as I specified, your rifle will achieve true enlightenment and you will never miss a target.

 

[l115a3]

20-22" for Tactical Rifle
24-26" for All around
30-32" for FTR


Depend on purpose.

 

[remington patriot]

Some very valid points here. I have an 18.5" 1:12 on order and I am even considering going to 18" and calling it a day.

 

[Dallas4rceMarine]

Oh no. I mean exactly 22.731415926"

You see, since 22/7 was the ancient closest approximation of Pi and 3.1415926 is Pi out to 7 decimals, if you construct the barrel length as I specified, your rifle will achieve true enlightenment and you will never miss a target.

you can't argue with that, its pure science!

 

[emaher308]

I have a 20 and 26 I personally like my 26 better for ftr comp I shoot

 

[popapi]

24" Bartlein on my Beanland .308!!

 

[RobertB]

I have a 16, 2 20's, a 22 and a 24

I highly recommend a 20 or 22. My fav is the 16 right now but I would go 20-22 if I could only have one. So really I like 18-20. Lol

Good luck.

 

[Grindl]

I run 26" right now , with the proviso , that I can always cut it later on . As I learn the magic number for re-loading what "she" likes . Instead of the old : Crap ! I cut it three times , and it's still to short .

 

[308220]

Anything from 18-22" is perfect. Anything more is just a hassle and gets it the way. 22" is the most ill have on any gun. If it wont shoot as fast as a 30" target barrel, then so the fuck what? It is what it is. And Im fine with that. Ill still hit my target.

 

[Lrdchaos]

I would say 23, it has enough barrel to get the velocity up there. Plus you can run a mid length suppressor and be just under 30 in total length.

 

[devldogs55]

Please allow me to think out loud here for a minute...

Well I've been doing a lot of searching all over the Hide - and just read this thread very carefully. I currently have a factory 20" Rem barrel that's 1:12 and has about 700 rounds through it. I'm not having any trouble with it - but I really want to get more out of it than I currently can, and I've been considering a re-barrel to get a 1:10. I started off looking for a factory take-off, but have been having trouble finding one. Now I'm considering buying a "custom" barrel in 1:10 and having the action trued at the time of install... I think this is the route I'm going to take - but my two biggest questions were barrel length, and contour - until today. Now I'm curious again how barrel length would change which twist rate is best - because it seems from reading this thread that people favor 1:10 in 20" barrels but prefer something more like 1:11.25 for longer barrels, or am I just making that up?

My goal is to be able to stabilize 175-185s better than my current 1:12 which doesn't seem to have good results even with only 175s. I am new to shooting at anything more than 300yds, so I'm working my way up - but in reality the majority of my shots will be within 600yds. I know the 168 will do it just fine, but I'm interested in going heavier. From what I've learned, I thought 1:10 would be the best twist for these bullets no matter what the barrel length, but now I'm not so sure.

As for length, I do really like the 20", but I'm not doing any "tactical" work with it other than messing around. I am envious of those that have the funds to have one rifle for each purpose, but I do not have the funds myself. This rifle currently serves as my coyote gun, lowland deer rifle, and steel plate ringer. right now I feel like I can find justification for 20"/22"/24" barrels - so I'm really just curious if 1:10 would still be the best twist for any of those lengths for 175-185s.

 

[kraven251]

other than this guy's tendency to confuse accuracy and precision, I found the results interesting.

The Truth About Barrel Length, Muzzle Velocity and Accuracy - The Truth About Guns

 

[hahco]

1-12" is plenty to stabilize Sierra 175's in the .308. If you're having accuracy issues, it's something other than the twist itself.

 

[devldogs55]

I'm not trying to open that can of worms, since there seems to be dozens of threads on the best twist for .308 and certain bullet weights already.

Mostly curious if the 1:10 has a different effect on the bullet from 20" to a 24".

 

[Niles Coyote]

[MENTION=99032]devldogs55[/MENTION] I have been shooting 308's with a 1:12 twist for few years now and in my experience a 1:12 will work fine, 190 berger VLD is the heaviest/longest I have used in my 1:12 308s... But, if you are going to rebarrel, get yourself a 10 or at least a 11 twist if you plan on running a steady diet of 175's and heavier. Bryan Litz performed a lot of testing for his latest book and this subject is covered thoroughly. He had multiple barrels made in 1:12, 1:10 and 1:8 twists testing velocities and BC's... well worth the read.
Modern Advancements in Long Range Shooting: Volume I

Again, there is noting wrong with using what you got until you need a new barrel but the gains you will get with the longer and heavier bullets are worth the faster twist.

Barrel length is a very personal decision, I would never want a barrel under 18" in a 308 but, others love them... I also see a reasoning behind 26" barrels because shooting 175's approaching 2800 fps is nice as is a very mild load that still turns in 2650fps. If its a bolt rifle and I was forced to only have one length I would choose 23" and a 10 twist, on a auto I would go 18" and again a 1:10 twist... but that's just me and my opinion... and my opinion changed after reading Bryan's work as I used to recommend 1:11's and I cant bring myself to recommend a 1:8 twist yet after having a bad experience with one.

"Mostly curious if the 1:10 has a different effect on the bullet from 20" to a 24"
The twist has a greater effect than the additional velocity the 4 inches will give you but you could see about a 3% gain in BC from what a 1:12 would give with the heaver/longer bullets.

 

[madarcher427]

What weight & bullets ? Twist rate?

A heavy 16 to 20 inch barrel is the way to go. Having a shorter barrel is better because it is stiffer and is more accurate in my experience. It's also easier to maneuver. Going from a 24 inch barrel to a 20 inch barrel your only losing around 50fps in velocity. That's not much. A 16inch barrel will easily get you out to a 1000 yards or more. In that Magpul DVD they shot out to a mile with a 16inch and 20 inch barrel

 

[sib1948]

As you have seen there are many factors to be considered here. Barrel length will affect muzzle velocity. Barrel twist (1/10 or 1/12 etc) will affect how much spin you get, which will affect the stability of the bullet in flight. So you have to ask yourself what type of rounds you intend to use? Light weight 147gr, med weight 168gr, or heavy-weight 200+ (subsonic) rounds. Will you be using a silencer, or muzzle brake, etc? Will you be using and light barrel, or a heavy barrel?

With all that being said, and the above answers to your questions; I'd say that a 20" barrel will be the best of all worlds.

Happy shooting.

This absolutely nailed the answer to the question. Twist rate, bullet rate and distance shooting should determine the barrel length!

 

[devldogs55]

Thanks for the additional insight into this question, Niles.

 

[Joe-n-TX]

20" for my 308. 1k is an awful long way. In my parts 600yds is pushing it. If I had a desert or BLM next door I'd use a different caliber.