Barrel length / Distance / Accuracy ?

[Iam2taz]

I am about to buy an AR 15 or 10. (undecided which one.) Stainless Steel Barrel. I have a question regarding barrel length / distance and accuracy. (If I wanted to go out and shoot at praire dogs for example.)
Typical lengths are 16", 20" and 24." 1.9 twist. If I am shooting a .223, what are the expected differences in barrel length for longer distance targets? Say 200 yards? There is a lot to be said about reloads and weight of the bullet, etc. But this is a general question. Our local range will go out to 250YDs.

Is there a difference in shooting .308? (Other than the cost of shooting the gun.) There are somethings that can be shot at 1,000 yds plus. But I probably won't see it to shoot to begin with!

If I just buy ammo off the shelf? Put it in a gun, off the shelf. What can I expect?
Assume I don't know anything, which is pretty true as this is my first AR and second rifle.
I am greatful for any help!

 

[Sky]

Good question I have been wondering about long distance shots myself. The 16" 1/7 should not give you any problems at 200 yards for p-dogs. At 300yds if you got some really good optics maybe you can; I tend to hit 14" metal plates and one coyote at that range. Was lucky on the Coyote was aiming at the shoulder but neck shot was the result; he jumped up and spun then fell.

We got some guys here that have the longer barrel ARs so it will be interesting on what they have to say. I just think out past 300 the 223 may not be a round for anything larger than a small varmint?

Jack Rabbits are easier they are taller and tend to stand up....sometimes..

A long barreled Ar-10 from what I have seen is over $1000 just for the upper. That coupled with ammo and mags cuts me out of the game for just shooting Jacks.

Still would like a 20" or longer barreled AR-15 but I still have "Black Rifle Fever"!

 

[Jim Watson]

A short barrel can be as ACCURATE as a longer. The Texas Warehouse Tests came up with 21.75" as the optimum for the usual benchrest calibers. We get a lot of gunzine writeups about how the stubby patrol car trunk guns are just as accurate as any.

BUT: The longer barrel has some advantages.
It gives a longer sight radius if you are using iron sights. Not important if you scope.
It gives free higher velocity for trajectory and windage. Not much at 200 yds.
It moves the muzzle blast farther away from your head. A bigger help than you might think.

 

[Iam2taz]

Thanks Jim.
I think I will look for the 20" barrel. I will be starting with iron sites. The scope I want costs more than the gun. (Imagine that!) Incidentally, there is some good info on www.ar15.com/

Have a great day.
Taz

 

[Zak Smith]

Since this is the Competition forum - what type of competition are you building this rifle for? We can give you a very specific answer what the best setup is given the game you name.

With regard to "Longer distance", 200 yards is still close range. To draw some broad categories for calibration, mid-range is maybe 300-600, and long range is maybe 600-1200. (Anything past there I put in extreme long range.)

.223 is a marginal long range performer. Even .308 is merely halfway competent at 1000 yards, compared to the cartridges that are used to win mid and long-range matches (those where you have some freedom of cartridge anyway).

For long-range, you want to use high BC bullets, at least 0.50-- 0.60 is where great performance starts. In .223, the best you can do to approach this are 77-80gr bullets (in the 0.36 - 0.44 range, with some exceptions). In .223 these bullets require a 1:8 twist or faster.

A longer barrel is advantageous for long-range shooting because both wind and drop are reduced with more muzzle velocity.

For a long-range .308, I would not recommend shorter than 22", 24" more preferable.

 

[Iam2taz]

Thanks Zak,
You have answered my question indirectly. I am sorry for placing the question in this area of the forum. - It seemed like a good spot at the time.

 

[zeepool]

1x7 16.5" 80gr open iron sights--- bulls at 50 to 400 yards. Get on paper at 600 but pray for black.

 

[Iam2taz]

Thanks Zeepool. Good bit of information to consider. Short barrel, good distance and accuracy.
Have a great day!