5.56/.223 ?

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Lightsped

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What is the difference? I am in the market for another AR and am not sure what the differences are in 5.56 vs .223. Accuracy, price, quantity, etc.....?
 
powderbrass said:
5.56 is actually .218, not .223 Look here and you will find everything you want to know about the 5.56 cartridge. http://www.thegunzone.com/556dw.html

Errr... I agree that 5.56mm is equal to .218 inches in terms of unit conversion, but that's not the difference between the 5.56NATO and .223 Remington cartridges.

The link you posted has an explanation of the difference between the two cartridges, as well as the Ammo Oracle link.

The difference is that 5.56NATO is loaded to higher pressures than the SAAMI specifications for .223 Remington. Also, 5.56NATO chambers tend to have longer throats and more headspace than a .223 Remington chamber.

The bullet used in a 5.56NATO is the same bullet diameter used in a .223 Remington.
 
I believe you can shoot 223 in a 556 chamber but you cannot shoot 556 in a 223 chamber because of said pressure problems:D
 
I use them both as the same and never had a problem.
How tech you wanna get on this ?
 
With regard to the 5.56 ammo and .223 ammo the bullets are exactly the same.

The ammo-oracle has a tremendous amount of detail on the differences including the sutble but meaningful differences. Its many mb of information.

I know it is said that some 5.56 can cause high pressures in a .223 chamber but I have never ever heard of a single incident in which it mattered one way or another. I own both caliber designations and have reloaded for both of them.

If someone has first hand or documented knowledge of a blow up with 5.56 in a .223 chamber let us know. I am always open to correction on this board because we have some great experience and talent here.
 
basicly 5.56 has higher preasure.

How much higher or enough to make the gun go boom? Dunno...but I will let others be the guinea pigs and report.
 
Coltdriver said:
If someone has first hand or documented knowledge of a blow up with 5.56 in a .223 chamber let us know. I am always open to correction on this board because we have some great experience and talent here.

So even though we know for sure the pressures will exceed the standard max, I'm not sure it's OK to do just because nothing has blown up yet.
 
put simply the 55.6 roudn is a little hotter, the case a little thicker, for mil spec purposes. you should be able to fire both in anything, with no problems. no mfgr makes a bolt action rifle that will fire 223, then fail at 556.
 
Odd. I just went through that myself. I went to the local gunshop to pick up some .223REM and they were out. The nice lady (seriously) sold me some 5.56mm, and off I went.
I got home, and was having doubts about firing 5.56mm in .223REM, recalling that warning: "only fire ammunition in firearms chambered for it." Hop on the web for a quick search and found out:

SAAMI says no.

Winchester says no. (the ammo I got was whitebox 5.56mm, I wanted the other white box)

Ruger says no. (M77 MkII, nice little rifle, btw)

I'm not going to a guinea pig either, despite reports that other people have done it.

I returned the ammo for a trade in a flavor pack of .223 REM, including some of that natec stuff.

Take care.
 
what I would want to see is just how much higher the preasure is, and then see at what preasure the individual gun is made to withstand before going boom...in a bad way.
 
I doubt the 5.56 would blow up a gun that has a tight .223 chamber. There's enough safety factor built into guns these days that are greater than the pressure differences between a .223 and a 5.56.


I still wouldn't try it though.


This is why you hear of "red box" and "black box" Hornady TAP. One is saami pressure, the other NATO. Being 75gr and loaded hot, the red box is not available to civilians (well, not suppose to be anyway) out of fear they'd load it into some ultra-tight .223 chamber and have some pressure issues. They know that law enforcement is going to be using good quality modern firearms. Bubba might be using some very old, or in bad shape .223 bolt gun with a tight chamber.
 
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