Longer Range 5.56 20" vs 24"

[Bravo Whiskey]

Longer should be better ,but all things being equal, should you step up to a 24"?

[Tomcat088]

Before I answer the question, I'd like to ask what exactly you define as "longer range"? What bullets do you intend to shoot this distance and with what twist? Do you intend to do it in a gas gun (AR or other semi auto), or do you intend to do it in a bolt action rifle? We kind of need to know some of those things before we can give you an honest and more accurate answer.

[mojo]

Bravo just bought an AR ... so that with the 5.56 in the title, I'm going to guess he is asking about ARs.

[knight0334]

The only thing the 24" will offer over the 20" is a tad increase in velocity(probably 80-120fps) giving a few feet extra range. Your sight radius will be the same, so mere addition of the 4ins wont increase accuracy by that virtue.

What particular barrels are you looking at? Grade differences? Twist rates? Barrel profile differences(heavy, varmint, etc)?

[thatJeffguy]

This is about the only place in the world where you'll hear guys and ladies both tell ya that four more inches just don't matter ;-)


It'll make the weapon heavier, sure. But if you've got recoil issues with a 5.56mmNATO.... time to break out the 10/22 bull barrel ;-)

[Lycanthrope]

It won't matter to accuracy, but it will shoot a bit flatter due to increased velocity.

Some 26" guns, like the White Oak Armament barrels have a special length gas tube. They will shoot a tad softer. Since these guns are used often with globe sights, the sight radius IS increased (the sight is often clamped by the muzzle).

Lycandetailsthrope

[Bravo Whiskey]

I have put the parts together for a basic M4 so I have been keeping my eyes open for a longer barrel for the next build. There are so many directions to go that I am just trying to learn so if I come across a "RRA 20" SS P.P. or wilson 24" SS Heavy " I may have a clue as to what I might grab.

I am thinking AR 5.56 flattop 20"/24" w/nice bipod and of course a good scope. I would like to learn to be able to shoot good groups out to 300/400meters (possible?).

Thanks for all the help w/ this and other posts.

[d90king]

I would say no. Test have shown that velocities that used to be achieved out of a 20" are now being achieved out of a 16"...

I ordered a LaRue OSR .308 in a 18" after debating the 20"... They also offer it in a 16" length...

[thanker92]

Some recent tests have shown the rate that the powder burns as having a lot to do with the velocity. IE: If all the powder has been burned and all the gas expansion has taken place then any barrel length AFTER that will actually slow the bullet down....Who knew?

[Lycanthrope]

Most of your good accuracy powders like Varget are slow burns and like longer barrels. Powder choice is a huge factor if you want a tack driver.

600 yard shooting is pretty common with the AR, but you want the 1:7 twist to use the 77+gr bullets.......not the 1:12 twist varmint barrels.

You're not going to find a better barrel for the dollar than the White Oak Armament barrels....which are wilson blanks cut by Compass Lake, I believe. Mine have shot dimes with reloads.

Lycan300metersiseasythrope