.308 in a 16" barrel...does this work?

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I recently read a comment (somewhere?) that has suddenly caused me to question some arms in my safe. Is it true that the ballistics of a .308 WIN (NATO) diminish to similar ballistics of a 7.62x39 when fired out of a 16" barrel?

If this is true then it has huge implications on some of my rifles. Does one need to be at least implementing an 18" barrel for the round to reach it's potential? What then happens out of a 16" barrel to .308win? Is there any value in these carbines that shoot .308 out of 16" barrels besides how cool they look? :scrutiny:
 
In a 16 inch barrel the 308 loses a lot of velocity...but not enough to make it a 7.62x39mm. (the 308 shoots heavier bullets)

I've seen 16" SBR's "bang the gong" at 600 yards with boring regularity.
 
It's close to true. .308 150gr FMJ will probably exit a 16" barrel at 2500-2550fps depending on the gun and the brand of cartridge. In comparison 7.62x39mm 123gr will exit a 16" barrel at about 2300-2400fps. So a fast x39 is nipping at the heels of a slow .308. As already noted the .308 bullet is still heavier; it will also have a significantly better ballistic coefficient. So the .308 will still have a significant advantage, but it won't be nearly as large an advantage as the .308 in a 22" barrel has over the x39 in a 16" barrel (the more common comparison).

An 18 to 20" barrel is a pretty good compromise for a .308. Longer provides more velocity but at a diminishing rate. Shorter produces a lot of blast. I've shot a .308 with a 14.5" barrel and a muzzle brake and it's a deafening, mind-blowing experience. Blast is felt up to 20' away.

Here are two articles of interest:

http://www.tacticaloperations.com/SWATbarrel/

http://www.loadammo.com/Topics/October05.htm
 
308 Winchester has no problem pushing 150 grain bullets into the mid to high 2700 fps range from a 16" carbine or a 15" hand cannon. Blowing both 30/30 and x39 completely out of the water even with much longer barrels
 
I would not worry about a 16" 308 barrel so long as its not your long range gun. I can think of nothing nicer for medium game at medium ranges to carry through the mountains and woods.
 
I shoot 308 out of a custom 16"BBl TC Prohunter - 3/4" @ 100yds - I dont think my target cares about a 100 or 2 FPS!!
 
My 16" Saiga pushes 145 gr. Brown bear in excess of 2600 FPS. It could likely exceed that with a different load.

I cannot remember what I Chronoed the wolf 124 x39 loads at.

I shot both a large empty fire extiquisher. The .308 went through both side. The x39 went in but didn't exit. The 5.7x28 40 grain Vmax load left a small dent.
 
To the 300m line, I note no difference in ability to hit targets out of the 8.5" SBR V51 as the 21" FAL.

It depends on the ranges you're dealing with and what you want out of it. When comparing apples to apples, make sure you look at equivalent barrel length and functional accuracy.
 
I agree with above dude; I have a 308 saiga, and it is significantly faster than a 762x39, and you can just tell, it is still hitting much harder... I have both rifles , with 16 inch bbls.
a 308 cart, is average centerfire speed, with average pressures, so from 20 down to 16 inches, it may---MAY LOSE 50 fps, on average per inch of bbl , but not any more than that.
 
Did some chrono work a while back between my Winchester M14 and SOCOM 16. I used Winchester White Box (147gr FMJ), Winchester FailSafe (150gr), Federal Urban Tactical (165gr), Federal Gold Medal Match (168gr), South African NATO and Hunter Shack Munitions (150gr FMJ Police).

The HSM load out of the SOCOM is almost identical to the NATO round out of the M14. The HSM ammo is good stuff.

M14

WWB 2790fps
WFS 2658
FUT 2679
FGM 2537
SA 2707
HSM 2841

SOCOM16

WWB 2671
WFS 2575
FUT 2547
FGM 2433
SA 2540
HSM 2703
 
Yep...I was gonna say that too krochus (blows em outta the water).

I have a 308 T/C with a 14 " barrel and can get 175's to nearly 2,400 fps.
RIGHT!

Or to put it another way I have a 26" barreled 7.62x39 and all it'll muster is 2250 fps with factory 154grn ammo.

In other words you could safely say that there's not a barrel difference big enough to place .308 in the same ballistic slot as 7.62x39mm
 
IMHO, taking a .308 Winchester and putting it in a 16" barreled rifle is a fools errand. The barrel is simply not long enough to take advantage of the cartridge's case capacity. Of course, if you like a large muzzle blast...

Don
 
unless... weight and mobility are more important than 150 fps
 
IMHO, taking a .308 Winchester and putting it in a 16" barreled rifle is a fools errand. The barrel is simply not long enough to take advantage of the cartridge's case capacity. Of course, if you like a large muzzle blast...
Opinions and insults seem to go hand in hand, I don't know what is wrong with having a short fast capable rifle in a modern caliber and configuration.
If that particular rifle is not as efficient as one 6" longer my bet is the difference is made up in ease and speed of use.
A lever action carbine has long been touted as the perfect brush gun so whats wrong with a bolt or pump carbine?
 
I hunt with a Savage Striker in 308 and the ballistic difference between a longer barrel and my 15" pistol barrel is not as much as you would think. I haven't chronoed mine but people that have has only seen a 150-200 fps decrease in the shorter barrel.. go to the Hodgdon website and look at their ballistics for the 15" pistol velocities.
 
...right, and look at the above dudes velocities; all less than 150 fps. Sounds plenty good to me.

I love that HSM ammo as well, I got some fantastic VLD bullets, and even some nice hunting style/soft point VLD's from them as well, quite accurate stuff, all in 243. I believe they load Berger bullets.

these guys...http://www.thehuntingshack.com/
 
Opinions and insults seem to go hand in hand, I don't know what is wrong with having a short fast capable rifle in a modern caliber and configuration.

Hey, if that's what you want, have at it. Just be aware of the huge muzzle blast you will be generating (won't be popular with the guys next to you on the firing line).

Don
 
Hey, if that's what you want, have at it. Just be aware of the huge muzzle blast you will be generating

It booms more than a x39 but is not nearly as bad as you are making it out to be.
 
I'm guessing a 308 out of a 16" barrel is likely better than a 44 magnum out of a revolver. Point being, you've got plenty of power behind it. I would feel quite safe with it.
 
I'm guessing a 308 out of a 16" barrel is likely better than a 44 magnum out of a revolver.

The 14.5" 308 I shot (a POF-308, slightly customized) with a muzzle brake had the most terrible blast of anything I've shot or been near, including a .50 BMG with a brake and a variety of magnum handguns. It was bordering on painful with 33db hearing protection at an outdoor range.

OTOH my 18" PTR-91 wasn't too terrible. I have not shot a 16" .308 so I can't comment on that exact configuration.
 
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