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Ranger bj
06-20-2011, 6:34 AM
Is there an optium barrel length for the .308 caliber bullet? I don't want to get too long of barrel if I don't need it.

21SF
06-20-2011, 7:11 AM
Max range intended?

Optimum for what?

Ranger bj
06-20-2011, 7:36 AM
As to the range, I'd like to reach out as far as the bullet can go and still have good knock down capabilities.

I know for a 223 caliber, most people say a 16 inch barrel is all you need to get the most out of that caliber.

Thanks

Hozr
06-20-2011, 8:51 AM
You'll get a TON of opinions here but the load, bullet, and platform are as important as the barrel length. For my ar 308 running 175 gr the 18" heavy barrel was the best length. Above that there wasn't much in the way of increased muzzle velocity but there was a huge amount of vibration decreasing accuracy.

What rifle and what round are you planning on? Long range weapons are a different game than ARs (15s). You need to start from a load and build for it.

Teletiger7
06-20-2011, 8:58 AM
" I'd like to reach out as far as the bullet can go and still have good knock down capabilities"

Shooting out to 1000? You'll want as much velocity as you can get. If you don't care about anythingelse like weight/handiness of the rifle, 30" Barrel.

tiger222
06-20-2011, 9:08 AM
18 is the best for handyness and range on a 308. I also like 12" , also no brakes on any bbl under 18 IMHO - too much concussion.

kozumasbullitt
06-20-2011, 9:11 AM
I think the perfect length for a bolt gun is 24", if you go to long then whip is a factor and to short velocity is a factor.

tiger222
06-20-2011, 9:14 AM
To add 18" is also best on a 223 to get the max performance. Lastly 21" is most pleasant on a 308 for extended shooting.

Bhobbs
06-20-2011, 9:19 AM
26-28 inches for best range. Power is related to speed so you are back to a longer barrel.

If you want a bolt .308 for long range shooting get a Remington 700 SPS-V. It comes with a heavy 26" barrel and makes a good starting point for a precision rifle.

mixicus
06-20-2011, 9:21 AM
Bolt action or semi-auto? Iron sights or optic? Do you reload or use factory ammo? Is this primarily a range or field rifle?

Iggy
06-20-2011, 10:04 AM
On a bolt gun: 20-21
Gas: 18-20

Read a post i just wrote on another thread:
http://www.calguns.net/calgunforum/showpost.php?p=6625276&postcount=16

phish
06-20-2011, 10:19 AM
32"

Ahhnother8
06-20-2011, 10:25 AM
for a 223 caliber, most people say a 16 inch barrel is all you need to get the most out of that caliber.

AR 308 running 175 gr the 18" heavy barrel was the best length. Above that there wasn't much in the way of increased muzzle velocity

Neither of the above statements is true. Maximum velocity for either round is achieved in a 32+-" barrel. Near maximum velocities are achieved in 28+-" barrels. Any shorter than that, figure a loss of about 50fps for every inch. These are general 'rules of thumb', and max velocity may not be the only goal.

As to the range, I'd like to reach out as far as the bullet can go and still have good knock down capabilities.

With a long enough barrel (velocity), at 1200 yards the bullet is still supersonic. How far is far enough?

21SF
06-20-2011, 10:50 AM
I like mine at 24-26"

OutlawDon
06-20-2011, 11:38 AM
As to the range, I'd like to reach out as far as the bullet can go and still have good knock down capabilities.



Let's get realistic and detailed...how far is the range you shoot at and what exactly are you wanting to knock down?

Hozr
06-20-2011, 11:48 AM
Neither of the above statements is true.

How do you figure? What part of my statement do you find to be UNtrue? 50fps gain for every inch of barrel, So another 800fps? I'm already pushing 2600+fps in a gas gun. I can reach 1000 and remain supersonic no problem. Is 3200fps really required for a gas gun not to mention all the extra weight hanging off the front of an aluminum receiver as well as barrel whip/harmonic issues? Do you want to actually hit anything?

Like I said, for my AR308 the 18" heavy barrel is the right choice out to 1000 at least. I've done a ton of research, thank the Britts, and there is no real gain above the 18" barrel for an AR platform. Bolt guns are a different story.

Bhobbs
06-20-2011, 12:05 PM
How do you figure? What part of my statement do you find to be UNtrue? 50fps gain for every inch of barrel, So another 800fps? I'm already pushing 2600+fps in a gas gun. I can reach 1000 and remain supersonic no problem. Is 3200fps really required for a gas gun not to mention all the extra weight hanging off the front of an aluminum receiver as well as barrel whip/harmonic issues? Do you want to actually hit anything?

Like I said, for my AR308 the 18" heavy barrel is the right choice out to 1000 at least. I've done a ton of research, thank the Britts, and there is no real gain above the 18" barrel for an AR platform. Bolt guns are a different story.

OP didn't say 1k. He said as far as possible.

Iggy
06-20-2011, 12:10 PM
I think 50fps per inch is a little much. I think it's more like 15.

This is an old article, but I still think it has some valuable info:
http://www.tacticaloperations.com/swatdec2000/index.html

Hozr
06-20-2011, 12:12 PM
The maximum effective range of 308 is considered to be 1000 as it generally goes subsonic past that and will be pushed around by the wind quite a bit. Yes hits can be made out to 1200 and beyond but they take some serious equipment and skill.

motorwerks
06-20-2011, 12:15 PM
Is there an optium barrel length for the .308 caliber bullet? I don't want to get too long of barrel if I don't need it.

If you ask this question to 100 people you are going to get almost 109 different answers. :D

I like the 18 inch for my AR in .308 but some like their 16's others their 20's bolt guys seem to go from 18'' to 26'' or 28''? It has a lot to do with bullet length, and weight, and intended use.

Army GI
06-20-2011, 12:24 PM
As to the range, I'd like to reach out as far as the bullet can go and still have good knock down capabilities.

I know for a 223 caliber, most people say a 16 inch barrel is all you need to get the most out of that caliber.

Thanks

What I can gather by the questions you ask is that you want a handy rifle without sacrificing too much velocity. My suggestion, in .308, would be a rifle with an 18-20" barrel.

Like most things when it comes to ballistics, you optimize one thing you sacrifice another.

When it comes to long range shooting, longer is better. Increased barrel length means increased velocity. But then you sacrifice handiness of the rifle, a rifle with a 30" barrel like my 1898 Krag-Jorgensen makes for a nice gun for shooting at long range with iron sights. But it is pretty cumbersome to move around, even just taking it out of the back of the car.

When you opt for a shorter barrel, you sacrifice velocity. This can be compensated partly by loading your rounds hotter or adjusting your sights to compensate for bullet drop. But, again, those hotter rounds would shoot that much flatter in a longer barrel.

What you do gain is increased handiness of the rifle. A rifle with a 16" barrel is very easy to carry around and shoulder off hand. When you are carrying equipment, a slung carbine is much easier to manage than a slung rifle with the barrel flopping all over the place. Even the M16A2 with its 20" barrel is a nuisance when slung under the shoulder.

Army GI
06-20-2011, 12:25 PM
If you ask this question to 100 people you are going to get almost 109 different answers. :D

I like the 18 inch for my AR in .308 but some like their 16's others their 20's bolt guys seem to go from 18'' to 26'' or 28''? It has a lot to do with bullet length, and weight, and intended use.

Absolutely.

I think it is 50% intended use and 50% personal preference:p

send it_hit
06-20-2011, 12:31 PM
looks like you need something right between 16" and 34"... :rolleyes:
:hide:

qaz5109
06-20-2011, 12:33 PM
why dont you go with what ever is the best deal in price then try reaching out as far as possible chances are that you may not even be able to shoot out to 1000yds until u get some time under ur belt 2 pennies

Bhobbs
06-20-2011, 12:34 PM
The maximum effective range of 308 is considered to be 1000 as it generally goes subsonic past that and will be pushed around by the wind quite a bit. Yes hits can be made out to 1200 and beyond but they take some serious equipment and skill.

He wants to shoot as far as possible. That means he will want the highest muzzle velocity with high BC bullets which are heavier. To get that MV he needs a longer barrel. No where does he say in the op that he wants it to be handy. He said as far as possible.

If you put a 30" barrel on a .308 bolt gun you can get the heavies moving up close ot 3,000 fps which will make it quite a bit further than 1K.

jeffrice6
06-20-2011, 12:42 PM
From my research the .308 reaches a full burn after 20" Guys still punch paper at 1000 yds with that barrel length, although, don't know the lethality at that distance.

Rock6.3
06-20-2011, 12:53 PM
From my research the .308 reaches a full burn after 20" .


That should vary by powder burn rate, not all powders will perform the same.

jeffrice6
06-20-2011, 2:37 PM
That should vary by powder burn rate, not all powders will perform the same.

Agreed.... But its a pretty safe blanket statement.

pontiacpratt
06-20-2011, 2:39 PM
My 700 SPS-V has a barrel length of 26"...that is what it came with so that is optimum for me as I cannot afford to rebarrel it.lol

Army GI
06-20-2011, 4:40 PM
From my research the .308 reaches a full burn after 20" Guys still punch paper at 1000 yds with that barrel length, although, don't know the lethality at that distance.

That sounds about right. However, for virtually any caliber velocity is still increasing up until 40+ inches of barrel length. For the kind of the shooting most of the general population does (100 yards or so) barrel length really doesn't matter and is mostly personal preference. On the other hand, while shooting long range with short barrels is achievable, you will not be competitive against shooters with longer barreled rifles.The farther your target, the more that last 100fps matters.

frankm
06-20-2011, 4:59 PM
As to the range, I'd like to reach out as far as the bullet can go and still have good knock down capabilities.


Then your .308 should be a .30-06. More end oomphf at long distance.

Bhobbs
06-20-2011, 5:13 PM
Then your .308 should be a .30-06. More end oomphf at long distance.

True. I have a 700 in .30-06 for that reason but there're no factory heavy barrel bolt guns in .30-06.

Ranger bj
06-20-2011, 5:51 PM
Everyone-

Thanks for all your replies. They are all really good.
I just got off work, and here's more information.

The guns I'm looking at are Tikka Super Varmint and Remington 700 heavy barrel 20" in tactical model and 26" in the Police model. All are in .308. The Remingtons are going for $550 and Tikka for $895. All are used rifles.

Also, what are the chances that the barrels have been worn out to point of loss of accuracy? I know buying used guns from unknown people can be risky.

Thanks Again for all the replies.

Bhobbs
06-20-2011, 6:02 PM
.308 has great barrel life. You would have to shoot thousands of rounds to degrade it.

Army GI
06-20-2011, 6:03 PM
There is honestly no way of knowing unless the previous sellers have told the gun shop owner how many rounds have been through it or if they let you gauge the chamber and the muzzle wear yourself.

Army GI
06-20-2011, 6:04 PM
.308 has great barrel life. You would have to shoot thousands of rounds to degrade it.

True, but I'm thinking more in terms of improper cleaning with steel cleaning rods and what-not.

mixicus
06-21-2011, 8:03 AM
"Also, what are the chances that the barrels have been worn out to point of loss of accuracy? I know buying used guns from unknown people can be risky."
I expect 5-7K rounds before I start seeing match grade accuracy deteriorate with 308's. Depends how hard you push the round. Unlike hosing with a semi-auto, that's a lot of rounds thru a bolt gun. You'd need to shoot a 60 round match every other week for 2 years to start seeing issues. Looking at the roles on the CA Precision Rifle matches or at SMGC, there just aren't that many people banging away that often.

In the rifles you list, the 20" will be just fine. If you look at the majority of set-ups from smiths such as GA Precision or Tactical Ops, they use 20"-24" barrels on the 308's.

In a recent precision type rifle class, with ~20 shooters all but 1 using 308's bolt guns; vast majority of the guns were ~20". There were a few 26" and there wasn't a noticeable performance difference in the barrel lengths. Distances were out too ~500yds with just about everyone using Federal Gold Medal Match 168's. Everyone driving the rifles were experienced shooters in the discipline.

If you were getting a custom set-up, matching the barrel length to the sport/need has advantages. For instance, if you were shooting iron sight in a PALMA match, the longer 30" barrels have distinct benefits mostly the longer sight radius.

MongooseV8
06-21-2011, 8:42 AM
However, for virtually any caliber velocity is still increasing up until 40+ inches of barrel length.

How is that possible when there is no more powder burning to build up pressure?

Bhobbs
06-21-2011, 8:46 AM
True, but I'm thinking more in terms of improper cleaning with steel cleaning rods and what-not.

Yeah that can happen but if you check out the muzzle and barrel before you buy it you should be good to go.

bombadillo
06-21-2011, 8:47 AM
I'm a fan of heavy barreled 20" .308 barrels. They're still putting out enough velocity to get out as far as you want to take them, but handy enough to deal with and just great all around. Not too heavy, not too long, not a little short stubby guy, or anything else. Either way, great length.

Coded-Dude
06-21-2011, 8:52 AM
tag

DocSkinner
06-21-2011, 9:08 AM
Let's get realistic and detailed...how far is the range you shoot at and what exactly are you wanting to knock down?

Definitely - "long range" has many meanings, and varies from person to person.
Realistic hunting ranges (Up to 400 yards)?
Long range hunting (400-600yards)?
Long range shooting (out 1000 yards)?
Going for sniping records (out to 2000 yards)?

What are you going to use it for?

If you are hunting out to 400-500 yards is pretty long if you intend on being able to find the game after you shoot it. A .308 in 18" or 20" will do fine at that distance, and take game very easily, and be a light rifle and maneuverable. The deer/pig/etc won't really notice a 100-200 FPS difference in the bullet that is hitting it, and with good shot placement you can take anything in North America with that.

If you aren't going to be carrying the rifle at all, and want to shoot 1000yds, get the long heavy barrel. But you aren't going to want to be carrying a 12-15 pound rifle around the hills, or trying to maneuver a 30" bull barrel around in the woods or brush, or trying to swing it on target for a quick shot.

If you want to get the absolute maximum you want one of the long range bench rest rail gun setups. And the cart you will need to help get it to the bench.

It all depends of what you plan on doing with the rifle.

DocSkinner
06-21-2011, 9:14 AM
How is that possible when there is no more powder burning to build up pressure?

The gas is still expanding and exerting pressure.