Best Barrel Length for .308?

I have done my research online, talked to some precision rifle guys, and if you ask five guys you can get 7 answers. I have seen guns that shoot well everywhere from 16-28", and solid arguments for most of those sizes. But I cannot sort enough out, and you guys are good at being honest, and explaining shit.

This article is nice, but has some gaps (e.g. jumps from 26" all the way down to 18") and is still but one example. http://www.thetruthaboutguns.c...locity-and-accuracy/

 

Specifically, I ask because I am going to get my PSS threaded (probably by GA Precision as I can drive over there) to take a brake/suppressor mount. Expect to mostly shoot with the suppressor after that. 

While I am at it, and adding that much more to the muzzle most of the time, do I have them knock a bit off the end? If so... how much???

Gun is: Remington 700 PSS, 26" starting length, 6R, I believe 1:12. I live in KS and mostly shoot therefore between 600-1200 ft altitude, at least for now. 

Today it shoots around (legit) 1/2 moa with Fed GM308M2, which is a tidge better than the '09 LC M118LR I was previously shooting. It can do more like 1/4 moa if you handload but I do not do that really, so let us talk of it no more. 

Would like to optimize for long range, such as it is for .308. Used to do 168s, but this holds that accuracy out to 900 at least with the 175s. Hoping as early as this spring to do more formal shooting, get to some "local" PRS-format matches and try it (and myself) out. Say: 100-1,000. 

 

My thinking: 

Take the chart from the test I linked above. As I have seen many times in many calibers, many guns, length has no direct bearing on accuracy and I will assume GAP can crown properly, and there's nice barrel all along so that does nothing much to my accuracy. So, it's about speed and how much I loose for that extended range: 
Let's say I loose 75 fps as per that link (which goes from 26 all the way down to 18) which does have Fed 175 on it even. 
Per some ballistic calculating, that would seem to knock me subsonic at about 1150 instead of 1200 yds (wx/altitude dependent). Which is already at the extreme range anyway, and at the edge of my ability to dial in range on the scope anyway, so... does it matter? I think I'd be happy with a 1000 yd gun any way you cut it.
 
Last measurement is that cutting to 18" leaves about 2" from the (bare... there will be a brake) muzzle to the lens of the clip on when it's attached. While that's enough clearance for the suppressor, and under night vision I'd clearly want to use it with the suppressor for flash/recoil, what IF I have to shoot without? Is that getting too close, so risking damage to the optics? 

The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life. – Theodore Roosevelt

 

Joined: 19NOV2004   Location: Mission, Kansas

Original Post

The TTAG article got their information from here:

https://rifleshooter (DOT) com/2014/12/308-winchester-7-62x51mm-nato-barrel-length-versus-velocity-28-to-16-5/

Charlie Milazzo, a very well known rifle smith and technical advisor to the American Sniper Association cut our Remington 700 barrels to 20.5 inches as he said that provided for a complete powder burn and was most efficient.

I’ve seen Clint Smith on tv say a 21” barrel in .308 was the most efficient.

I have a Tikka T3x CTR with a 20” barrel, and have a SilencerCo Saker 7.62 I use on it.   I wouldn’t want it any longer.    

I’ve only shot out past 700-800 yards once, though...  I was able to get a 2nd round hit on an Iron Maiden at 1125, and a 5th round hit at 1245 (left handed after the wind picked up).   All with a 20.5 inch barrel using 168gr TAP.  

Bottom line, I think there a lot more important variables that you can change to get better hits out there, e.g. better caliber, buy a Kestral, better tracking glass; than an inch or two of barrel length.  

"To be born free is an accident; to live free is a privilege; to die free is a responsibility." - Richard Secord

Joined 08/25/2008.   Location: Northest WI

I like 18" on a 308, especially suppressed. I've done the 16" and 13" thing and I really think 18" is the sweet spot. 13" is just too blasty.

If you want to go further than say 800 yards get another caliber. If I am going to put a 24-27" barrel on there it will be with a round that will make it worth it; one of the 6.5's or a 338.

 

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and my handwriting is barely legible,

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You know I've been there when you hear...

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Hootiewho posted:

... If you want to go further than say 800 yards get another caliber. If I am going to put a 24-27" barrel on there it will be with a round that will make it worth it; one of the 6.5's or a 338.

Oh yes. I think I meant to — in my other flood of info — admit that this is just a .308, so reliable 800 or even 1000 is awesome, but if I get my own land or otherwise have a reason to shoot way over that regularly, I'll get a second precision gun in a different caliber. I am not on the lookout for say, a scope with more elevation clicks. 

The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life. – Theodore Roosevelt

 

Joined: 19NOV2004   Location: Mission, Kansas

I did a velocity work up using SCARs and various ammunition types with both 13" and 16" barrel lengths. When I get back to my laptop Ill see if I cant post it here.

Rick

The essence of war is violence. Moderation in war is imbecility. John A. Fisher

Not the easiest format to understand - but the details are below. All were 5 shot strings.


 16” Scar

M118LR

AVG – 2504
SD – 22.1
Max – 2531
Min – 2476

MK316

AVG – 2532
SD – 13.8
Max – 2552
Min – 2518

M80 Ball

AVG – 2606
SD – 27.3
Max – 2651
Min - 2583


13” Scar

M118LR

AVG – 2424
SD – 8.6
Max – 2432
Min – 2410

MK316

AVG – 2442
SD – 6.3
Max – 2449
Min – 2434

M80 Ball

AVG – 2527
SD – 16.7
Max – 2549
Min - 2512


 The average velocity loss in going to a 13" gun across all of the loads was only 83 FPS.

Rick

The essence of war is violence. Moderation in war is imbecility. John A. Fisher

The only problem with a can on a rifle is carrying it.

A folder eliminates most of the problems associated with a can on a bolt gun.

So, while you're going by GAP, drop by Manners and look at a folder for your shooting stick.

Stick with the barrel length you want and don't worry about length. Mitigate those issue by adding a folding stock.

My 22" GAP Crusader .308 is a dream.

My 16" Tikka TACA1 is handier to climb with though.

 

JS7SFGA posted:

The only problem with a can on a rifle is carrying it.

A folder eliminates most of the problems associated with a can on a bolt gun.

So, while you're going by GAP, drop by Manners and look at a folder for your shooting stick.

Stick with the barrel length you want and don't worry about length. Mitigate those issue by adding a folding stock.

My 22" GAP Crusader .308 is a dream.

My 16" Tikka TACA1 is handier to climb with though. 

GAP had a lot of stocks on the shelf (99% Manners), and they let me (made me?) fondle a bunch for an eventual project I am working towards: want an EFR, as now the clip on is screwed to the scope bell and is... not awesome, but current stock doesn't have enough meat to handle it, so new stock time, and that means new bipod time, and... stuff to decide as well as save up for.

Aside from the MUCH higher cost, I had seen complaints the folders were not as rugged, reliable, accurate even. Not sure I followed, but you have a folder on the... which gun? 

The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life. – Theodore Roosevelt

 

Joined: 19NOV2004   Location: Mission, Kansas

I have several. I like my Manners MCS. I like my Mcree (heavy but rock solid. I like the Tikka TacA1 (their chassis. Very solid).

I have zero issues with them all.

I found once I started running folders that all subsequent choices spec'd that out as a requirement.

Best is a moving target. How a rifle handles, balances,  and what you're doing with it make a difference.  

I have a 22" .308 bolt gun and an 18" .308 bolt gun. They're set up similarly. I prefer the 18" just for general handiness. If I were really shooting long range - as was said above - I'd be looking at a different caliber. In fact, I'm already looking at a Tikka 6.5CM. I keep trying to talk myself out of it. The main argument I come up with is i get free .308 and .223. That's a helluva good one. But if I were paying out of pocket for ammo, and I had a range over 900 yards available without traveling, I'd have already done it. 

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Joined: 12-2005          Location: Central OK

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