.223 vs 5.56 accuracy beyond 500 yards

[C-dub]

Good morning and Happy New Year to everyone!

This is not your typical question with these two types of ammo. While visiting a friend and his family last night something was said and it has me a bit stumped. I mentioned how well I think I've shot a few of my rifles out to 200 yards and would like to try getting it out a bit further and mentioned the Top Gun range in McKinney. That's when it was brought up. So far, they've been shooting .223 and would also be interested in going out to 500 yards, but needed to get some decent 5.56 ammo in order to that. My friend told me that .223 was good out to about 300-400 yards and beyond that 5.56 was good/better out to around 800.

Is there any truth to this?

I've been searching the interweb and think I've come up with something. There is some truth to this, but it is rifle and ammo dependent. I think either round has about the same accuracy at the same distance as long as it is fired from the appropriate rifle. Shoot 5.56 from a 5.56 barrel/chamber and a .223 from a .223 barrel/chamber and accuracy will be pretty close if not the same. However, shoot .223 from a 5.56 barrel/chamber and this is where differences show up because of the throat differences. Am I close?

[KC80]

55gr bullets will get you to about 300yds, 62gr maybe 500yds. Will probably need heavier to reach 500. With 55gr I can hold 5/8"@ 300yds. At 400yds all accuracy goes out the window. This is just what I have found.

[android]

Ammo quality is more important. The $1.00 / round Federal tactical ammo groups much better than the XM193 or 223 bulk pack stuff. I've seen no real difference between .223 or 556 in my AR type rifles. Maybe you would see a more definite difference in a bolt action target rifle.

[C-dub]

Heavier bullets are a given and also let's assume that each are of equal or relatively equal quality. If the ammo is basically the same except for the .223/5.56 difference does it come down to the barrel/chamber or is this just a myth/misunderstanding?

[cbr6864r]

It can be done out past 500 yes but your talking major bullet drop and crazy lateral movement if there is any wind....toss in a short barrel (sub 20") and best of luck

[Lena]

I have done a lot of long range shooting in the past and tries the 223/ compared with a 6mm there is a huge difference, Huge, we were getting very few hits at that distance with even the heavier bullets , switching to my 6mm's we had prairie dog kills repeatedly up to 1000 yds especially with the 105 gr vld's from a 6 Ackley or 6/284, conditions were perfect, 5-600 were no problem at all even with the 70 gr tnt's. The 223's simply did not do anywhere as well at all.
My 223 that day was a Shilen DGA action with a 26" SM 1:9 twist at 26" #7 contour.
My friends with the 700V bolt guns got a few hits, just a few compared to the 6s' and just quit wasting ammo. remember I was shooting at rat size targets nothing like the 500 yds we shot to qualify with M16's.
Even the 6BR of mine with 68-70 gr shot well at 500 compared to the 223.
My friends 223 Ackley did ok with 69gr bullets and is a great caliber and easy to load for.
We had 24 to 36x scopes and Leica range finders to verify plus walked 1/2 way to target area and ranged front and rear and added to verify distance. If your really serious about shooting that distance it can surely be done but a larger caliber will give you much more success.
I do have (my favorite rifle) a 22/6mm that I shoot 68-69 gr bullets in that will do it with no problems but not like the 6mm will.
6mm case necked down to 224.

[C-dub]

Lena, that's really cool info and thanks. However, I'm not planning on shooting my M4 out to that distance. I'm happy with it mostly for CQC and occasionally out to 200 yards. I did better than I thought I would at that distance with only iron sights and my non-magnified eotech.

This is merely a something that came up that a friend of mine is interested in doing. I doubt it is something that they want to do seriously or on a regular basis. Just something they want to try. The part I'm curious about is that they insisted the .223 was insufficient or unreliable to be used beyond a certain distance, but that the 5.56 was okay. It's bugging me and I haven't been able to find out anything to support or refute their claim myself and thought I'd ask here.

[Beiruty]

To answer you. What you heard is all heresy.
Accuracy/precision is matter of
1) Rifle capability
2) Shooter capability
3) Factory ammo consistency
4) Handloads are tuned to resonate with the barrel so when bullet exist the barrel, the barrel's muzzle (exit side) would be at rest.
5) Wind and weather conditions.

As for 223 vs 556.
Facts:
1) 556 is faster than 223. That is it is loaded at higher pressure.
2) Heavier bullets would have higher BC
3) High BC bullets are better for long range shooting
4) High BC bullets would keep their velocity higher at long distance
5) High BC bullets would resist side winds better at at long distance
6) Longer barrel would generate faster Muzzle velocities 25 fps / inch
7) The shooter who makes an average rifle a precision shooting rifle.
8) Practice until you exceed the capability of your rifle/ammo at a given range
9) For long range a Ballistic Calculator on your Smartphone or the old school data book are the key for hit or miss
10) Accurate range reading are the key for hit or miss
11) Accurate Reading for Weather condition, especially wind are the key for hit or miss

[texasmusic]

Bullet selection will be more important than 223 vs 556. Beyond 500 yards I'd be shooting some type of 70-77 gr match bullets. Mk 262 is popular & can be found for 60 cents or so.

223/556 has to do with the max pressure, & there are some differences in the chamber as well. So the edge would go to 556 if the ammo was the same consistency & same bullet, due to the higher pressure available. The availability of higher grain loaded ammo in the 5.56 may help as well.

[threoh8]

The Service Rifle competitors do well out to 600 yards, with AR's chambered for either 5.56 or .223. Most handload, so the difference is minimal in their loads. They tend to use faster twist barrels across the course (7" to 8" twist), and many switch to single-loaded (too long for the magazine) 75 or 80 grain match bullet loads for 600.

Either is legal for Palma matches (800, 900, and 1000 yards, prone with iron sights), but those tend to be very specialized rifles and loads. 5.56/.223 is not the favored cartridge. Reading the wind becomes even more critical.

If I wanted to reach out with a .223, I'd see what it could do with heavier bullets at intermediate ranges. If it did OK, I'd try longer ranges until it didn't.

[Pawpaw]

I can't answer your question directly, but I can tell you my own experience.

Rifle: Colt LE6520. This has a 16" pencil barrel with a 5.56 chamber and 1x7 twist. I changed out the trigger group for a CMC single-stage.

Scope: Trijicon TA01 ACOG. This is a 4x32 scope with BDC markings out to 800 yards. According to Trijicon, it is calibrated for XM193 (5.56) ammo.

Ammo: Fiocchi .223 - 77gr Sierra Match King.

On a calm summer day, I was able to hit a 3' steel gong at will on any of the 5 targets painted on it. Not only that, but I was holding dead-on the 500 yard mark in the scope.

At this particular range, I had to hit an 8" steel plate 3 out of 5 times at 200, 300, & 400 yards before I was allowed to shoot the 500 yard gong. I never missed, using the BDC reticle at the appropriate yardage.

Maybe the sun, moon, and stars just aligned right that day. All I know is that I was hitting so consistently that it got boring and became just a waste of good ammo.

[Beiruty]

I can't answer your question directly, but I can tell you my own experience.

Rifle: Colt LE6520. This has a 16" pencil barrel with a 5.56 chamber and 1x7 twist. I changed out the trigger group for a CMC single-stage.

Scope: Trijicon TA01 ACOG. This is a 4x32 scope with BDC markings out to 800 yards. According to Trijicon, it is calibrated for XM193 (5.56) ammo.

Ammo: Fiocchi .223 - 77gr Sierra Match King.

On a calm summer day, I was able to hit a 3' steel gong at will on any of the 5 targets painted on it. Not only that, but I was holding dead-on the 500 yard mark in the scope.

At this particular range, I had to hit an 8" steel plate 3 out of 5 times at 200, 300, & 400 yards before I was allowed to shoot the 500 yard gong. I never missed, using the BDC reticle at the appropriate yardage.

Maybe the sun, moon, and stars just aligned right that day. All I know is that I was hitting so consistently that it got boring and became just a waste of good ammo.

That is for sure, Top gun range.

[Pawpaw]

That is for sure, Top gun range.

Right you are, my friend!

[Bitter Clinger]

Assuming a constant bbl length and twist rate, you can only draw conclusions when comparing specific rounds, viz:

Hornady 5.56 NATO "Superperformance" 55 gr GMX, 3190 fps @ muzzle, 47.9"" DROP AT 500 yds. (not for use in .223 chamber!)
vs., e.g.,
Hornady 223 REM, 55 gr V-MAX, 3240 fps @ muzzle, 45.9" drop at 500 yds.

YMMV.

[The Annoyed Man]

Hornady Superformance .223 75 grain Match. Nuff said.

I have shot this accurately at 500 yards at Tacpro, dinging a 2/3 scale IPSC steel silhouette target at will at that distance with my 18" DMR. I posted about that range day a year or two back.