Accuracy of a 20" barrel vs a 24" barrel

[Nowhere Man]

I've found a Savage Model 10 Precision Carbine in .308. It comes with a 20" bull barrel.

How much acuuracy am I giving up with the carbine vs the 10 FCP-K with a 24" barrel at, let's say, 500 and 1000 yards?

Dave

 

[TonyAngel]

I'd say that all things being equal, the shorter barrel will be more accurate. What the longer barrel will give you is more velocity which will probably give you more range because the bullet will stay super sonic for a longer range. Stated differently, I'd say that the shorter barrel is more accurate over its useful range than a longer barrel will be over its useful range. Short barrels seem to be all the rage right now. I saw a guy at the range a few weeks ago with a 16.5" .308.

The point is that a longer barrel does not equal better accuracy. The only exception would be if you are shooting iron sights. If that is the case, the longer sight radius on the longer barrel may help YOU to shoot more accurately.

My .308 has a 22" barrel. My buddy's .308 has a 26" barrel. Same barrel blanks and same smith cut the chambers and did the installs. They both shoot one hole groups. His rifle gets about 60-70fps more velocity than mine for any given load. That's the only difference in performance.

From a practical standpoint, mine is lighter (but certainly not light) and easier to deal with in the field. His recoils a tad bit less.

Get the one that you think looks cooler and has the advantages that mean the most to you.

 

[USSR]

Individual rifles are accurate or inaccurate, and it has nothing to do with the length of the barrel. You will give up velocity with the 20" vs. the 24" barrel, and if you intend to shoot at 1,000 yards, then this is something to consider with a .308, which IMHO, is a marginal 1k round.

Don

 

[Nowhere Man]

Sounds good to me.

Thanks, Dave

 

[Coal Dragger]

At 500 yards you will not see much real practical difference, however at 1000 yards where the .308 is going to be near the transition between supersonic and subsonic you will want that longer barrel to give you more velocity. The higher velocity will pay dividends in keeping the round supersonic and therefore more accurate at longer distances.

 

[jmr40]

Accuracy will not be affected, if anything the shorter barrel may be more accurate. While longer barrels tend have more velocity, individual barrels vary. I have a 20" barreled 308 that shoots most loads 10-15 fps faster than my 22" barrels. Expect the longer barrel to be 50-75 fps faster at the muzzle, but don't be surprised if it is less than that.

 

[Coal Dragger]

Perhaps with factory ammo, but if you reload and use a slower burning powder the longer barrel will pay off.

 

[jmr40]

That is with hot reloads.

I also used to have 2 rifles chambered in 280. The Ruger was always 75-100 fps faster than the Winchester. Both had 22" barrels. Individual rifle barrels have at least as much to do with velocity as a couple of inches of barrel.

 

[TonyAngel]

I really don't think that 4" of barrel will make enough of a difference in velocity one way or the other. Get the one that you think looks better or has the more apporpriate twist rate. If one has a 1:10 twist and the other a 1:12, I'd go for the one that suites your needs.

Personally, I couldn't make up my mind either, so I went with a 22" Krieger barrel with a chamber cut for 168gr Federal Gold Medal Match. With a 175gr SMK loaded to an OAL of around 2.775 (my chamber is short) using a charge of Reloader 15, I'm getting 2700 fps ten feet from the muzzle. Even at 2600fps, that should keep you super sonic out to 1000.

 

[CraigC]

Individual rifles are accurate or inaccurate, and it has nothing to do with the length of the barrel.

What he said! Disregarding, of course, the needs of high level benchrest shooters to have the bullet exit the barrel at a specific point in its rotation. Most shooters aren't looking for that extra thousandth. Those that do, don't ask.