Barrel length 20" compared to 24" & 26" in 30.06?

[CaptainCrossman]

old thread, good topic- 20" is too short for the 30-06 cartridge for hunting with full on loads and 150-220 grain bullets. It's not in regard to accuracy or power, but in regard to muzzle blast and noise. It kills your ears. Most replies will state "I took this or that animal with it no problem" on a short barrel. Well no kidding, so will a 44 magnum DA handgun with a 6" barrel for that matter. The real question is, do you want to put up with the muzzle blast in your ear from the shorter barrel from an 06, and a gun that kicks like a mule. It does a number on your left ear. (or right ear if your a left handed shooter). The best I can describe it is, blowing off a 1/4 stick or M-80 in midair only 20 inches from your ear with no protection- get the picture ? That would hurt, and so does the 06. The little extra barrel length goes a long way to move the pressure blast away from your ear. The 06 has a pretty large powder capacity for a non-magnum cartridge, it's not a low intensity round like a 30-30 or 32 Win Spl. or 35 Remington. You really don't want a 308 or 30-06 or 8x57 with only a 20" barrel, unless you have hearing protection. The recoil and blast will be excessive because these guns usually are pretty lightweight as well. 22" is optimum on the short side for a barrel. I've found 24" to be ok as well. 25" and longer is too long for woods hunting.

 

[jmr40]

There is a reason most manufacturers have settled on either 22 or 24" as standard for the 30-06. Those are the best balance between velocity and handling. You pick one or the other to get a rifle that looks and balances the way you want it to, not because of velocity. There isn't enough to matter beyond 22", at least not on a hunting rifle. Going to 26-28" might give you 50-100 fps more speed over a 22" barrel. On a 1,000 yard target range that might matter, not on a hunting rifle.

You will often see folks quote figures of 10,20,or 50 fps for each inch longer or shorter. On average this is about right depending on the chambering, but it is not linear. Going longer than about 22" in a 30-06 gives you very small gains per inch, and the gains continue to be smaller as you go longer. Going shorter the losses get larger and larger the shorter you go. If you were to chronograph loads from a 26" barrel then gradually shorten it 1" at a time and chronograph it at each length until you get to 16" you'd see around 250-350 fps total loss for an average of 25-35 fps/ inch. But the velocity loss between 26" down to 22 would be very small and you wouldn't start seeing big chunks until after you get under 20"

Another mistake people make is comparing the velocities they get from 2 different guns. It is meaningless. Only the data compiled from shortening the same barrel and when firing the same loads under the exact conditions is worth looking at. Between family and friends I load for 7 different 30-06 rifles. 4 with 22" barrels, 2 with 20" barrels and 1 with a 24" barrel. My best loads of 150 gr bullets shoot at the following speeds from the 4 guns with 22" barrels

3025 fps
3015 fps
2990 fps
2965 fps

The 24" gun shoots the same ammo at

3025 fps

The 20" guns shoot the same ammo at

2900 fps
2910 fps

While that is a big loss compared to the fastest 22"or 24" barrel it is only 55 fps slower than the slower 22" gun. And still right at published velocities with factroy ammo from 24" barrels. They shoot factory ammo within 60 fps of velocitities published for 24" barrels.

Lots of folks say a 308 is a better choice for a 20" barrel. Maybe, but my 20" 30-06's are still 100 fps faster than factory 308 ballistics from a 24" barrel.

I guess muzzle blast is subjective. The 20" guns are a little louder, but I struggle to notice the difference. It is still quieter than a 24" magnum rifle. Weight is not a factor. Losing 2" of barrel is around 2 oz. The 2" can make a difference in really thick brush. I'm pretty happy with 22". The 24's just don't add enough speed to justify the awkward balance and looks in my eye. If others prefer that look and balance I have no argument. I rarely hunt with my 20" gun, because I just like the 22" ones better. But it's not a bad length if you want to use it.

 

[adelbridge]

A .30-06 out of a 20" barrel is going to perform about the same as a .308. Send a 7mm rem mag down a 22" barrel and it is going to give you .30-06 performance.

 

[B!ngo]

Would it be too much of a detour to restate the questions here for .308? I'm looking at a bolt rifle that has the option of a 20" or 24" barrel. I'll use it mostly for mid-range paper but also want to reserve the right to hunt with it every now and then, and just don't want to carry a clumsy rifle if the marginal value is small.
From the off-hand comments re .308 in this thread, it seems like 20" is a fair length for .308 but just would like to hear more. And perhaps asked differently, when would someone choose a .308 in 24"? I'm sure they don't make that barrel for nothing.
Oh, and yes I suppose I don't 'need' a .308, but always wanted one.
B
P.S. (let me know if you'd prefer me to post a new thread)

 

[trapper500]

Barrel Length

The longer a barrel is the better i like them. My 300 WBY Vanguard iam paying on has a 24" barrel & i wish it was 26" or 28".My wife's little 243win Mossberg TREK has a 20" barrel she likes it so its good for her.It does shoot good but the shorter barrel will effect the shot at long ranges my Handi Rifle 500 S&W mag has a 22" barrel & i love that little monster its get greater velocities over the shorter pistold barrels.JMHO

 

[451 Detonics]

I will go out on a limb here and say 21 3/4 inches is the perfect barrel length, not much velocity is lost and it is the best length for accuracy according to Virgil King. This is man who is used to shooting rifles that arc so I assume he know what he is talking about.

 

[Art Eatman]

The 21.75" number came from this commentary:

http://www.angelfire.com/ma3/max357/houston.html

"Secrets of the Houston Warehouse".