Max effective .223 barrel length
I am building a ar-15 and I am wanting to know what the max effective length of the barrel in .223/5.56? I see 20, 22, and 24".
0
-
"Effective" for what?
People who carry these things around and fight with them, often like shorter barrels for ease of carry, transport, storage, better handling especially indoors or inside vehicles, etc. That's worth more to them than another 100fps muzzle velocity which isn't really going to make any difference except with super-long range shots they're probably not going to take anyway.
Longer barrels make the most sense if you anticipate shooting at the extreme ranges of the cartridge.
If you're asking about velocity, that depends on exact load, but you typically hit diminishing returns at about 24". In other words, you may still get more velocity with longer than a 24" bbl, but only a tiny amount more.
See here:
http://rifleshooter.com/2014/04/223-remington5-56-nato-velocity-versus-barrel-length-a-man-his-chop-box-and-his-friends-rifle/
http://www.accuratereloading.com/223sb.html0 -
Even if you were going to use a super fast 1 in 7 twist, and shoot a 90 grain VLD bullet for ranges out to 1000 yards, using the slowest, suitable powder, the max barrel length would be 24 or 26". You can get them made to what ever you want.
I run that chambering out to 600 yards, and I could go further, as I have plenty of adjustment left, to get to 800 yards. I run 16" bull barrels for the stiffness. I shoot the Barnes 62 grain TSX in a 1 in 8 twist.0 -
+1 for a stiffer barrel. 0 -
My 6.5 twist 90 gr VLD shooter is 28".
Past the point of diminishing returns?
Maybe, but keep your hacksaw to yourself.
It is not a competitive 1000 yard F-t/R but it hammers at 600.0 -
After 24" on AR15 you're just showing off. 0 -
Generally speaking(someone can always find a specific instance to argue about), a 24" barrel will burn as much of a powder suitable for use in the .223 as the case will hold.
I own and shoot a pair of .223 bolt actions with 24" barrels. There will be "some" increase in velocity over a 20" with most of the commonly used powders. Some of the faster powders I use like X-terminator or AA2230 don't show a lot of increase since they're fairly efficient in 16-20" barrels. I don't use burn rates slower than H335/WCC844 since I have no real need for those. 55-60 grain bullets are as high as I go--if I feel the need for more bullet weight/range, I use bigger cartridges.
I'd prefer a stiffer, 20" barrel on an AR over a whippy 24". You may find the long barrel, slow powder combination causes malfunctions due to gas pressure level (dwell time)in the gas port to muzzle section of the bore.
I bought an AR upper that some dufus had cobbled together. He said "it never worked right". Double feed EVERY shot. Combination of oversized gas port and 24" barrel allowed enough gas to remain in the system to prevent the bolt from closing on the first fed round and cycle again, pushing another live round behind the first. I "fixed" it with an adjustable gas block and it's 100% BUT the long barrel is less accurate than any of my 20" AR's. Just a factor of barrel quality? Maybe or maybe a factor of increased barrel flex.0 -
Been doing some barrel lenght experimentation, although not in 223 , or semi auto
due to gas pressure operation.
yes with conventional powders you reach a max point per caliber. some calibers
require at least 26 in.
But if you select slow burning powders you can achive the same velocity
as the normal lenght barrel with less powder( cost), less muzzle blast, less recoil ( allows for better accuracy) better off hand due to weight forward, a extreme distance from front to rear iron sight which promotes accuracy. Problems are finding a gun case, moving around without striking the barrel end etc. Been testing all the way to 32 in.
No you dont get more velocity but you get other advantages at a cost of maneuverability
and may I add move your chrono further down range to get a true measurement of
bullet velocity.0 -
It was determined years back that a 2650fps striking velocity will break the 55 grain bullet in two at the cannilure giving two tumbling wound channels. The Russians were so impressed they came out with a 22 of their own.
Using Mil ammo, the maximum range for this effect was about 100 yards for the 16" barrels and about 150 yards for the 20" barrel.
At greater ranges you just get a pinhole. The disaster at Mogadishu
speaks for the ineffectiveness of 14" barrels.
While short barrels are more handy, one loses this special effect as this velocity isn't reachable at the target.
Ranges may be slightly off as I'm speaking from memory.0 -
Slightly off topic..I, several years ago, had shipped to me a brand 'spankin new M16A1 military surplus upper receiver/barrel assembly. Chromed chamber, and bore. Twist 1/12. Chamber dimensions set up for the 55gr M193 round.
I'm only posting this because the 55gr M193 dropped human targets 'dead in their tracks' just like the squad that I was with that was using 7.62 M180 ammo in their M-14's.
...again, another useless tidbit of information. Or is it? It's up to the reader to decide. Best to all, Joe0 -
1022man,
What you have found here with the variety of answers to your query pretty much holds true whenever this question is asked no matter the venue.
There are simply too many variables to attempt to take them all into account to give one simple answer except to say that there are too many variables. This means that it is up to you the shooter/reloader to determine what your needs are and what type of ammunition you desire to shoot. Then let the environmental decisions get sorted out by necessity or by simplicity. Will a shorter barrel be more convenient than a longer one? Will a slightly longer barrel be a better balance for both carry and shooting? You get the drift.
The .223 Rem/5.56x45 cartridge is extremely flexible, not only by the variety of commercial loads but the infinite number of variables available through reloading and powder selection. Check your reloading guides for the range of selections or read up on the performance data available for the commercial loads. Go to your local gun shop to handle some of the platforms with different barrel lengths. Then make an informed decision.
Best.0
Please sign in to leave a comment.
Comments
10 comments