I apologize, as I'm pretty sure this has been asked before. What's the difference between ammo labeled .223 and 5.56 Nato? Is it safe to run .223 through an AR platform that's chambered for 5.56? Where does the Wylde offering fall into this mess?

Thanks guys.

223 in a 5.56 marked barrel = Okay
5.56 in a 223 marked barrel = No
Wylde barrel = Good for 223 & 5.56

here's a better explanation:

http://www.americanweaponscomponent...aliber-confusion-223-wylde-vs-5-56-nato/

{ Edited to correct typo}

Rumor mill at the local gun shop ( I put very little faith in their knowledge. Almost none, really) is that the Wylde chamber wont handle (cheaper) steel 5.56 ammo well.

Any truth?

That brings up an other good point. I've been told to not shoot steel cased ammo. Is this an accurate statement for my PSA Ar-15 with a 1 in 7 twist barrel? Eliminates the cheap ammo for plinking purposes.

Steel works well in 7.62x39 because it's a highly tapered cartridge. The .223/ 5.56 by comparison is straight sides so steel is less prone to run well in any of these chambers.

I've had issues with steel even in factory 5.56 chambers.

I don't run it in any of my AR series rifles regardless of chamber.

5.46 in a 223 marked barrel probably is not okay but 5.56 in a 223 barrel is 100% OKAY. Same wrong crap gets recirculated via the wonderful web over and over.

I was just down stairs putting my stuff away from a range trip today. I've got a little over 100 rounds of steel cased stuff. Guess I won't shoot that any more. Thanks for the advice.

100 rounds won"t make a big difference.

Shoot it up but don"t buy anymore. Buy brass cased and reload.

5.56 loads are not 100% ok in .223 chambers. In a bolt gun, but factory loads, I generally don't worry about it, since modern bolts handle 65k psi just fine. But in the AR I have loads that are fine in 5.56 chambers that need to be backed of a full grain or they blow primers in a .223 chamber.

There is a non-trivial difference between the two, and you need to pay attention to it.

5.56 is typically loaded hotter than civilian .223
Never heard of a kaboom, but it is universally considered unsafe to run 5.56 in the tighter .223 chamber.

Although safe to use .223 ammo in a 5.56 chamber, it sometimes is too weak to run an AR that is tuned for 5.56.


This is correct (from above):

223 in a 5.56 marked barrel = Okay
5.56 in a 223 marked barrel = No
Wylde barrel = Good for 223 & 5.56

And there is some of that crap right there.

Wrong.

Wrong again.

Still wrong.

Really?

And exactly when did you shoot my rifles and handloads?

Most factory chambers are large enough that it ain't gonna matter but order a match 223 chamber and see if you don't have to back off.

Yep. Not going to create a life or death situation but shoot a case of Mk262 in a true match 223 chamber and see how far you get before malfunctions and broken parts.

Thanks for the good info here guys. I'm new to the world of the AR so this is all good stuff to know. Once again the men at the 'Fire have come through. Your help is greatly appreciated.

Your AR will more than likely gobble up everything.

Including steel.



Travis

I hate to break it to you all, but when it comes to a .223 marked barrel, you can't go by the barrel marking.

I have a Mark X Mini Mauser factory marked ".223 Rem" but it is a NATO chamber. I understand that Olympic or some other AR maker did the same thing on some rifles.

unbelievable how something so simple can get so derailed. at least everyone agrees that neither a 223, 546 nor a 556 will kill a pig.

Even some Colt rifles were marked that way.
In some European countries civilians are not allowed to possess military ammo.
That's probably why that Mini was marked that way.

Is it no coincidence that in the native tongue of the north, fairchase means kaboom ?

my barrel is marked 5.56 nato.
works fine with all brass cased ammo.
jams with steel cased ammo with the case 2/3 chambered. and i mean jammed. takes a half hour to remove.
parts ain't parts. and chambers are not all the same even when marked alike.
ymmv

And Ned Christiansen has a 5.56 throat reamer that will clean up lots of 5.56 marked chambers that aren't.

Wrong yet again. Nasty women. Loser. Trade mark.

Yep, you're wrong again
http://ar15barrels.com/data/223vs556.pdf
There is a difference

My Wylde does not like steel case ammo one bit. It jams up when trying to chamber a round. On the other hand, my 223/556 Bushmaster sucks steel case up and spits it out all day long.

Sure there is a numbers difference between 223 and 5.56 but it doesn't make any real life difference. Completely safe to shoot factory 5.56 in a factory 223 marked barrel. With 10s of thousands of 5.56 and 223 ARs in the USA and with millions of rounds of both ammo flavors flowing freely it is amazing there are not daily kabooms and equally impressive everyone knows not to shoot 5.56 in a 223 chamber.

Any chance you can find some "compelling" evidence on the www that the moon landing was faked, UFOs are real, the govt killed Kennedy, ........?