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ussrgago818
05-11-2014, 7:54 PM
I am a new owner of an AR-15 and have been experimenting with different brands of ammo and caliber 223 or 556. I have a 1x7 twist barrel and wanted to ask you guys what you think is the most accurate bullet or company that makes the most bullets.

jarhead714
05-11-2014, 8:03 PM
Get a different barrel with a faster twist if you want the most accuracy out of your AR. Black Hills makes a decently accurate 55 grain cartridge that should be pretty good out of yours though.

ArmedCMT
05-11-2014, 8:09 PM
OK, well what is your rifle chambered in(556 or 223) and what length is your barrel?

What ammo have you tried so far?

dtrump
05-11-2014, 9:36 PM
If you had a 1 in 7 id say 77 grain black hills ammuniton. But I think you could still use like a 69 grain of some sort well enough. I donno?

penguin0123
05-11-2014, 9:43 PM
If you don't reload, try Black Hills 69gr load that uses the Sierra Match King bullet.

Sleighter
05-11-2014, 10:08 PM
Ok, I'm not going to try to make any assumptions about your firearms knowledge, so this may be a review for you, or it may be new info, I don't know.

Your question is a complicated one, first off we have to determine what your rifle is actually chambered for. Second, what will work best in your rifle based on it's twist rate and barrel configuration.

First: There is actually a difference between the 5.56 chamber and the. 223 chamber, not to mention the way that the pressure ratings for each chamber are measured. In a nutshell, a 5.56 chamber has a longer throat (or leade) which is the very beginning of the barrel before the lands of the rifling.

You might wonder why that matters. Well there are 2 simple reasons that I can think of off the top of my head. 1) safety. If a bullet is forced onto the lands of the rifling because of a shorter throat (223) than the ammo is designed for, it increases the chamber pressure and the likelihood of mechanical failures due to overpressure. 2)accuracy. Different bullets like to fly at different velocities to achieve their maximum accuracy. They are particular little creatures. Depending on the "jump" (space before the lands) that the bullet needs to travel before it engages the lands will help determine the pressure and thus the velocity of the round.

So based on that, you need to determine if your rifle is chambered for 5.56 or. 223. Then find match grade ammo according to that caliber.

Second part of your question: barrel twist.
Once again, why does this matter? The twist ratio of your barrel determines how much spin is placed upon the bullet which helps to stabilize it in flight increasing both its inherent accuracy and maximum (stable) flight distance.

As a general rule of thumb: the faster the twist, the heavier the bullet that rifle can accurately shoot. However, think of twist as creating a range of bullet weights that your rifle will shoot well. By increasing the twist ratio you gain access to heavier bullets, but lose accurate access to lighter weight bullets.

Now, with all of that out of the way. Barrels are also unique and have a character of their own. Some barrels will like one bullet over another bullet, and as far as I can tell, there's no discernible reason why. It just it what it is.

That doesn't mean that all bullets are created equal. Far from it. A bullets concentricity, uniformity and weight distribution can all range from very poor, to very close to perfect, all depending on how much you're willing to pay. So for off-the-shelf ammo, for accuracy look for something that is open-tip match or something similar. The bullets are actually designed better and manufactured to more exacting standards, that is what makes them more accurate. It's not all marketing gimmicks. Also, bullet designs will have something called B.C. (ballistic coefficient) on their box or manufacturers website. The rule of thumb is: the higher the number, the farther the bullet will travel accurately and the less drop it will have. Thus:higher BC = flatter shooting. But if you're only shooting 100-200 yards, this isn't as important.

But all of that info above should help you understand why for superior accuracy you need to reload for your own rifles. Because two rifles built to the same standards will shoot identical rounds differently most of the time. The ability to custom tailor your bullets, velocity and jump to your specific rifle and needs are the key to utmost accuracy.

TL;DR version: Buy match grade ammo between 55 and 69 grains for your rifle of different manufactures and bullet designs and see what your rifle likes best.

Bhobbs
05-11-2014, 10:30 PM
Get a different barrel with a faster twist if you want the most accuracy out of your AR. Black Hills makes a decently accurate 55 grain cartridge that should be pretty good out of yours though.

Twist rate has nothing to do with accuracy. It only has to do with stabilizing bullets.

joelogic
05-11-2014, 10:34 PM
Twist rate has nothing to do with accuracy. It only has to do with stabilizing bullets. Which affects accuracy. ;)


Twist rate should be paired with an appropriate weight bullet. Then quality bullets can come into play.

Jimmybacon43
05-11-2014, 10:56 PM
These four things will make any bullet you shoot much more accurate :D

http://www.armystudyguide.com/content/army_board_study_guide_topics/m16a2/four-fundamentals-of-mark.shtml

k1dude
05-11-2014, 11:20 PM
The only way to find out what your barrel likes to eat is to feed it a varied diet and take good notes.

I've known 1:9 barrels that shoot best with 75 gr bullets and 1:7 barrels that shoot best with 55 gr bullets. Both of those instances defy conventional wisdom.

Test different loads until you find what it likes. If you reload, that's only the beginning of the fine tuning that you'll do. It takes time, work, and money to figure it all out.

If all you care about is plinking and 2 moa is fine, save yourself time and money and buy bulk ammo.

jarhead714
05-12-2014, 3:22 AM
Twist rate has nothing to do with accuracy. It only has to do with stabilizing bullets.

Yeah, but aren't heavier bullets accurate out to longer ranges?

penguin0123
05-12-2014, 5:12 AM
Yeah, but aren't heavier bullets accurate out to longer ranges?

Not necessarily. In a perfect world with zero wind, it wouldn't matter.

But a heavier bullet of the same calibre often means a longer projectiles, which means a higher length to width ratio. That gives it less drag (higher ballistic coefficient) assuming that ogive and base profile stay the same. This makes the longer projectile more resistant to crosswind and retain more velocity downrange. As you can imagine, it is easier to shoot a laser with zero drop than a mortar.

The trick with longer projectiles is to make sure they can be loaded to SAMMI OAL without compressing the powder and creating pressure spikes. The 90gr .224 projectiles are so long that they can only be single loaded and cannot be magazine fed. Another has to do with barrel twist: a longer projectile requires more twist to stabilize.

BHinkley
05-12-2014, 5:50 AM
It's elementary my dear Watson you want a projectile with both tangent and secant ogive and a high ballistic coefficient (BC) based on G7 and not G1.

I HOPE THIS CLEARS THINGS UP. :eek:

LCU1670
05-12-2014, 6:16 AM
Is this a 223 Wylde upper?

highpower790
05-12-2014, 8:07 AM
depends on the nut behind the trigger

jeffafa
05-12-2014, 8:50 AM
You might wonder why that matters. Well there are 2 simple reasons that I can think of off the top of my head. 1) safety. If a bullet is forced onto the lands of the rifling because of a shorter throat (223) than the ammo is designed for, it increases the chamber pressure and the likelihood of mechanical failures due to overpressure.

Are you saying that shooting .223 ammo in a rifle chambered in 5.56 is bad for the rifle and potentially dangerous to the shooter?

CSACANNONEER
05-12-2014, 8:58 AM
Bullet or loaded ammunition? There's a big difference. Then, you did not specify what cartridge your rifle is chambered for or what the twist rate is. Of course, even with all that info, the only way to actually know which bullet works best in your rifle at this point in it's barrel life (yes, even that makes a difference), you'll need to work up loads for various bullets to find out what is the best for now.

CSACANNONEER
05-12-2014, 8:59 AM
Are you saying that shooting .223 ammo in a rifle chambered in 5.56 is bad for the rifle and potentially dangerous to the shooter?

No, the other way around. shooting 5.56 in a barrel chambered for .223 could be an issue.

acaligunner
05-12-2014, 9:10 AM
I am a new owner of an AR-15 and have been experimenting with different brands of ammo and caliber 223 or 556. I have a 1x7 twist barrel and wanted to ask you guys what you think is the most accurate bullet or company that makes the most bullets.


A 1x7 twist barrel 'GENERALLY' likes bullets in the 69-77 gr group.

Black Hills company red box is usually considered the most constantly 'accurate' mfg, they also make a premium reloaded ammo in the blue box.

If you have a 223 chambered rifle, do not shoot 5.56 ammo thru it.

If you have a 5.56 chambered rifle it is OK to shoot both 223/5.56 ammo.

A 1x8 chambered rifle will also be OK to shoot 223/5.56 ammo.

1x7 twist rifles, generally lose some accuracy with 45 gr -55 gr bullets, they are generally considered to light for the twist.

That is all

Oceanbob
05-12-2014, 9:21 AM
http://i61.tinypic.com/nco0tv.jpg

russ69
05-12-2014, 10:25 AM
Get a different barrel with a faster twist if you want the most accuracy out of your AR....
That might be a little hard to do, 1/7 is a fast twist. You probably meant the other way around.

Twist rate has nothing to do with accuracy. It only has to do with stabilizing bullets.
Well, sort of. The idea is to just spin the bullet fast enough stabilize but not over spin it and cause yaw issues. Bench shooters use slow twists.

jeffafa
05-12-2014, 10:28 AM
No, the other way around. shooting 5.56 in a barrel chambered for .223 could be an issue.

Yep, after re-reading it that's what he was saying. Reading comprehension fail on my part.
I hate Mondays...

Germz
05-12-2014, 10:32 AM
Mk 262.
http://www.gandrtactical.com/images/archive/Blackhills%2077gr%20.jpg

Sleighter
05-12-2014, 12:49 PM
A 1x7 twist barrel 'GENERALLY' likes bullets in the 69-77 gr group.



Black Hills company red box is usually considered the most constantly 'accurate' mfg, they also make a premium reloaded ammo in the blue box.



If you have a 223 chambered rifle, do not shoot 5.56 ammo thru it.



If you have a 5.56 chambered rifle it is OK to shoot both 223/5.56 ammo.



A 1x8 .223 Wylde chambered rifle will also be OK to shoot 223/5.56 ammo.



1x7 twist rifles, generally lose some accuracy with 45 gr -55 gr bullets, they are generally considered to light for the twist.



That is all


Fify. I'm sure that was a typo. A .223 Wylde chamber is in between a .223 and 5.56 in throat length and can accommodate both calibers of ammunition.

A 1/8 twist barrel has no bearing on the caliber if the chamber.

acaligunner
05-12-2014, 12:53 PM
^

Smartphone typo. ;)

Sleighter
05-12-2014, 12:55 PM
Mk 262.

http://www.gandrtactical.com/images/archive/Blackhills%2077gr%20.jpg


This is potentially dangerous advice without know the OPs chamber caliber.

JMP
05-12-2014, 1:06 PM
Generally, I have good luck with the Lapua Scenars, but it depends on your gun.

Germz
05-12-2014, 5:18 PM
This is potentially dangerous advice without knowing the OPs chamber caliber.

I didn't give advice, I gave an opinion. :)
Also, we do know the "caliber"; its .22. The cartridge the barrel is chambered for is what is unknown.
Further, all I did was post a pic of a good quality 5.56 round, and you assumed that was me telling him to use it.

nbirnbaum2
05-12-2014, 8:41 PM
I prefer black hills match ammo... :) its $$$ but well its match ammo