.223 and 5.56 differentiation?

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Skillet

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So I am thinking about getting a first AR-15, and i need to know something. what is the difference between a .223 and a 5.56?

3 questions-

can a 5.56 calibered AR-15 shoot a .223?

can a .223 calibered AR-15 shoot a 5.56?

What is a good AR-15 to start out with that is $1100 and below?

thank you!
 
Well I wont get into the whole "which AR-15 is better" argument, but I will tell you a 5.56 barreled AR will shoot both 5.56 and .223. A .223 barreled AR will also shoot both, but the pressures created by 5.56 rounds are greatly above what the .223 produces. Shoot 5.56 at your own risk out of a .223 barreled AR.

Bass
 
Ok, no madder what anyone tells you I swear as a happy AR-15 collecter, the DPMS AR-14 M4 is one of the best of the best, they will feed and feed and feed and never jam and they hit the target dead on with a nice punch but almost no recoil.
 
From Wikipedia:

While the 5.56mm NATO and .223 Remington cartridges and chamberings are very similar, they are not identical.

Military cases are generally made from thicker brass than commercial cases; this reduces the powder capacity (an important consideration for handloaders), and the NATO specification allows a higher chamber pressure. NATO EPVAT test barrels made for 5.56mm NATO measure chamber pressure at the case mouth, as opposed to the location used by the United States civil standards organization SAAMI. The piezoelectric sensors or transducers NATO and SAAMI use to conduct the actual pressure measurements also differ. This difference in measurement method accounts for upwards of 137.9 megapascals (20,000 psi) difference in pressure measurements. This means the NATO EPVAT maximum service pressure of 430 megapascals (62,000 psi) for 5.56mm NATO, is reduced by SAAMI to 379.21 megapascals (55,000 psi) for .223 Remington. In contrast to SAAMI, the other main civil standards organization C.I.P. defines the maximum service and proof test pressures of the .223 Remington cartridge equal to the 5.56mm NATO.

The 5.56mm NATO chambering, known as a NATO or mil-spec chamber, has a longer leade, which is the distance between the mouth of the cartridge and the point at which the rifling engages the bullet. The .223 Remington chambering, known as SAAMI chamber, is allowed to have a shorter leade, and is only required to be proof tested to the lower SAAMI chamber pressure. To address these issues, various proprietary chambers exist, such as the Wylde chamber (Rock River Arms) or the ArmaLite chamber, which are designed to handle both 5.56mm NATO and .223 Remington equally well. The dimensions and leade of the .223 Remington minimum C.I.P. chamber also differ from the 5.56mm NATO chamber specification.

Using commercial .223 Remington cartridges in a 5.56mm NATO chambered rifle should work reliably, but generally will not be as accurate as when fired from a .223 Remington chambered gun due to the longer leade. Using 5.56mm NATO mil-spec cartridges (such as the M855) in a .223 Remington chambered rifle can lead to excessive wear and stress on the rifle and even be unsafe, and the SAAMI recommends against the practice. Some commercial rifles marked as ".223 Remington" are in fact suited for 5.56mm NATO, such as many commercial AR-15 variants and the Ruger Mini-14, but the manufacturer should always be consulted to verify that this is acceptable before attempting it, and signs of excessive pressure (such as flattening or gas staining of the primers) should be looked for in the initial testing with 5.56mm NATO ammunition.
 
1) Yes.

2) Not recommended. For this reason I only consider 5.56 guns for SHTF/plinker/truck guns. I'd only use a .223 chamber if building a match rifle, because a .223 chamber will be more accurate. The average shooter wont be able to tell a difference though.

3) Several sources. As far as off the rack rifles, I think Stag is the best bang for the buck ($900 OTD), with S&W just behind them (same gun from what I see for few more dollars). Also check CMMG's bargain bin. Colt LE6920s are around $1100 I think, maybe a little more.
 
AR

Picked up a Stag lower and upper a few months apart.
Put them together and Voila! Its so accurate its boring.
Little over $800.00 but I got the upper for cost.
I have owned Colt, BM and currently have the Stag and a RRA heavy. Just not that much difference between any of them.
 
Under 1100 your best bet is BCM. Frankly they are quickly becoming the standard. You get colt quality for the cost of a much lesser gun.
 
Don't take my word for it, but I will bet almost all mass-marketed .223 marked ARs have hybrid chambers for liability reasons, making shooting both 5.56 and .223 ammo completely safe. I know my Bushmaster made Remingtion R-15 is marked .223, but Bushmaster indicates it really has a hybird chamber (when contacted, Remington evidentally won't admit that). I assume Remington wanted it marked .223 because it is marketed as a 'hunting' rifle. Best idea is to check with the manufacter.

I would also assume that some specialty ARs built from the ground up for target work and marked .223 really are .223 chambered for accuracy reasons.
 
Don't take my word for it, but I will bet almost all mass-marketed .223 marked ARs have hybrid chambers for liability reasons, making shooting both 5.56 and .223 ammo completely safe

NO!!! One would, or even should, think that, but infortunately it is NOT that way.
The chamber designation will be marked on the sibe of the barrel.
ie... .223, 5.56 Nato, .223 Wyld.

Do not assume that all AR's are of the modified 223 type(experimental, DoD, but some was said to have been in public circulation) or the 'Wyld' type chamber, they are not!
 
So a semi auto marked .556 will take more pressure than a Mod 70 or 700 bolt marked .223
your joking right?
That is the common sense in me.
The reality is that they are in fact marked differently and there is a claim to unsafe pressures so shoot at your own risk. As for myself I have never worried and had no problems. I also load mixed brass and can't see a difference despite the brass thickness difference.
Some weaker actions like the Savage may not take the pressue as well but I have shoot many rounds of both in mine.
 
The chamber designation will be marked on the sibe of the barrel.
ie... .223, 5.56 Nato, .223 Wyld.
Good point.

Go by the markings on the bbl, not the lower. I know colt used to be real bad about marking a lower .223 with the bbl being marked 5.56.
 
It's a little frustrating. My Colt M4 is stamped .223 on the lower, and the barrel is 5.56
Then when I started to get into reloading, (knowing nothing when I started), I couldn't find the bullets.....because they are .224. ha. I felt stupid, but it was funny and makes sense after I thought about it.

I paid 1,200 for my colt. I also have a RRA. I have no idea what AR is best, just know I love both of mine, and I thought 1,200 for Colt quality was good enough for me. Best of luck.
 
So a semi auto marked .556 will take more pressure than a Mod 70 or 700 bolt marked .223
your joking right?

Let's keep it to the same critter.
We are talking about AR barrels, NOT bolt action rifle barrels.

Some weaker actions like the Savage may not take the pressue as well but I have shoot many rounds of both in mine.

Weaker????? Is the Savage actions, weaker??? Weaker than what?

ALWAYS go by the designation marked on the 'outside of the barrel', the manufacturer marks the barrel as to the chamber cut in THAT barrel.
You can put any barrel, marked any way, in the upper, so always go by the markings on the barrels.
 
ALWAYS go by the designation marked on the 'outside of the barrel', the manufacturer marks the barrel as to the chamber cut in THAT barrel.

+1
I have the DPMS and recommend it.
 
Quote:
So a semi auto marked .556 will take more pressure than a Mod 70 or 700 bolt marked .223
your joking right?

Let's keep it to the same critter.
We are talking about AR barrels, NOT bolt action rifle barrels.


Quote:
Some weaker actions like the Savage may not take the pressue as well but I have shoot many rounds of both in mine.

Weaker????? Is the Savage actions, weaker??? Weaker than what?

ALWAYS go by the designation marked on the 'outside of the barrel', the manufacturer marks the barrel as to the chamber cut in THAT barrel.
You can put any barrel, marked any way, in the upper, so always go by the markings on the barrels.
__________________
I am talking about chamber presure and the continued lament that 5.56 should not be used in .223 chambers. Since there are few commercial bolts chambered in 5.56 my question is valid since they do both have chambers and I contend that there is no danger in shooting 5.56 in bolt rifles because their chambers are inherently stronger than that of autos or pumps.

As to the Savage action, it is plenty strong but a Rem bolt will protect the shooter much better than a Savage. A high presure load can blow a case and pop the extractor as well as gas and brass. I found this while testing some 7-08 loads in a 788 and then switching to a Savage. I still have Savage rifles but have an understanding of their limitations.
That said I have had no problems shooting 5.56 in a Savage or Winchester bolt.
 
from my understanding... you can shoot .223 in a 5.56mm chambered rifle but not shoot 5.56mm in a .223 chambered rifle. There was something said about the pressures were different and the .223 may or may not be able to withstand the pressures. Most manufacturers make the barrels to 5.56mm NATO spec so they are safe to shoot with either round.
 
The difference might require a bizarre setup of circumstances for it to actually make a difference, but yes, they are different.

I am not aware of any ARs manufactured right now in .223, they are all 5.56 or Wylde hybrid chambers that can shoot both.

There is no reason to ever load any gun with a round different than what is stamped on the barrel.
 
can a 5.56 calibered AR-15 shoot a .223?

can a .223 calibered AR-15 shoot a 5.56?

What is a good AR-15 to start out with that is $1100 and below?

5.56 can shoot 223.

223 is dangerous to shoot 5.56.
There are some forum members who will tell you they've never had a problem and not to worry about it.

However, the firearms community does not agree with them:
http://www.saami.org/Unsafe_Combinations.cfm

http://www.fulton-armory.com/556-vs-223-Chambers.htm
Here's the problem. Many NATO cartridges have bullets that will become jammed into the rifling of a SAAMI chambering (the throat is too short). This is VERY DANGEROUS, for a great number of reasons.

http://web.archive.org/web/20080505.../lawenforcement/news/newsview.aspx?storyid=11
(Sorry for the archived link, but winchester took down the page. Thankfully, there's Archive.org. Give it a few minutes to load...archive.org is a bit slow sometimes)
Paul Nowak
5/4/2001
.223 Rem VS 5.56mm

There are a lot of questions about these two cartridges. Many people think they are identical - merely different designations for commercial and military. The truth is that, although somewhat similar, they are not the same and you should know the differences before buying either cartridge.

* The cartridge casings for both calibers have basically the same length and exterior dimensions.
* The 5.56 round, loaded to Military Specification, typically has higher velocity and chamber pressure than the .223 Rem.
* The 5.56 cartridge case may have thicker walls, and a thicker head, for extra strength. This better contains the higher chamber pressure. However, a thicker case reduces powder capacity, which is of concern to the reloader.
* The 5.56mm and .223 Rem chambers are nearly identical. The difference is in the "Leade". Leade is defined as the portion of the barrel directly in front of the chamber where the rifling has been conically removed to allow room for the seated bullet. It is also more commonly known as the throat. Leade in a .223 Rem chamber is usually .085". In a 5.56mm chamber the leade is typically .162", or almost twice as much as in the 223 Rem chamber.
* You can fire .223 Rem cartridges in 5.56mm chambers with this longer leade, but you will generally have a slight loss in accuracy and velocity over firing the .223 round in the chamber with the shorter leade it was designed for.
* Problems may occur when firing the higher-pressure 5.56mm cartridge in a .223 chamber with its much shorter leade. It is generally known that shortening the leade can dramatically increase chamber pressure. In some cases, this higher pressure could result in primer pocket gas leaks, blown cartridge case heads and gun functioning issues.
* The 5.56mm military cartridge fired in a .223 Rem chamber is considered by SAAMI (Small Arm and Ammunition Manufacturers Institute) to be an unsafe ammunition combination.



Before buying either of these two types of ammunition, always check your gun to find what caliber it is chambered for, then buy the appropriate ammunition. Most 5.56mm rounds made have full metal jacket bullets. Performance bullets - soft points, hollow points, Ballistic Silvertips, etc. - are loaded in .223 Rem cartridges. Firing a .223 Rem cartridge in a 5.56mm-chambered gun is safe and merely gives you slightly reduced velocity and accuracy. However we do not recommend, nor does SAAMI recommend, firing a 5.56mm cartridge in a gun chambered for the .223 Rem as the shorter leade can cause pressure-related problems.


So while there are those who haven't had any issues yet with 5.56 in a 223, the industry does not agree with the practice. Think of it this way: would you rather prove the industry wrong 100 times, or be the one who proves them right 1 time? Get a rifle chambered for 5.56, shoot 5.56 and 223, and have no worries. KISS method all the way.

[EDIT]If you're ever wondering about a firearm and ammunition compatibility, call the manufacturer.[/EDIT]

As for which AR, I have a Rock River Arms entry tactical. Have had no issues with it and it was $800 NIB about 3 years ago, and the setup is very nice and very comfortable. I have seen it again at the gun shows in the $800ish price range...which is good since they have been in the $1200 range during the buying rush.

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My R-15 IS marked .223 on the barrel, but the company that made it (Bushmaster) says it is really a hybid chamber. You are correct that by going with the marking on the barrel is the correct policy, that marking is not always the way it really is (by design). I have heard this is also true with many DMPS .223 marked barrels, but again, don't take my word for it. Contacting the company directly (someone not in the sales office) or making a chamber cast are the only ways to know for sure. Otherwise, going with the barrel stamp IS the best policy.
 
I am not aware of any ARs manufactured right now in .223, they are all 5.56 or Wylde hybrid chambers that can shoot both.

whether you are aware of them or not, there ARE ARs made with 223rem chambers. Not only that, but many of the chambers marked 5.56 are tight enough to cause pressure issues.


as far as i'm concerned, shooting 5.56 in 223 is substantially similar to exceeding the recommended max powder charges when handloading. lots of people do it safely all the time BUT it is utterly irresponsible for you to advocate someone else do it without knowing the specifics of their gun.


If YOU want to shoot 5.56 in your gun that is marked 223, I recommend you call your mfg and ask them if it is safe.
 
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