.223 vs. 5.56

[Hoosier]

I should probably search around the other sub-forums as this question might be answered, but...

What's the difference between .223 and 5.56? Can I run both through my rifle? I haven't looked but I assume my rifle is .223 stamped, I'll check later. I had been under the impression they were interchangeable.

Thanks!

[Irving]

Think of them like this:

5.56 = .357 mag
.223 = .38 special

It's not a perfect analogy, but if you follow that rule, you shouldn't break anything.

[StagLefty]

My understanding is that if the barrel is stamped 5.56 it will shoot both. If it's stamped .223 it's for that caliber only. I'm sure someone else will be along if that's not correct.

[sniper7]

okay quickly since I gotta get going...Rodizio grill here I come!!!!


.223 is the civilian version, 5.56 is the .mil version.

you want a 5.56 chambered gun. then you can shoot both 5.56 and .223 ammo out of it.
if your gun is chambered in .223, DO NOT shoot 5.56 ammo out of it as the higher pressure of 5.56 may cause damage to your rifle and potential failure.

also, don't look at the lower receiver as that could be false if the gun was a build. what is important is what is stamped on the barrel.
If you know it was a factory gun, you can go off the lower receiver, but if you have any doubts, go with the safe side.

also, most guns chambered in .223 are bolt rifles, or ARs used in competition. I have seen very few tactical ARs that were not 5.56 chamber.

[Hoosier]

Poop! I don't have any method of getting to the barrels on either of my rifles without taking off the floating handguards. My guess is they're both .223... one is 10 years old now.

Steyr AUG A3's are $1950... saving up for one of those, maybe I'll sell one or both of these Arrrr's to fund it.

H.

[Marlin]

*Should* be marked just in front of the front sight,, along with the twist rate...

[rl45acp]

Per Marlin, My RRA soild(?), non contured barrel is not marked anywhere.

If its an AR, I would think it is most likly 5.56. Do you know what brand upper it is? and more importantly, is it an unmolested upper? IE you bought it new and have never swapped the barrel.

Also, and you can all correct me if I am wrong, the 5.56 has a longer throat in the chamber, so couldn't one take a casting of the chamber to find out?

[hip55]

The AR15.com Ammo-Oracle

http://www.razoreye.net/mirror/ammo-...cle_Mirror.htm


Q. What is the difference between 5.56×45mm and .223 Remington ammo?

http://www.razoreye.net/mirror/ammo-...irror.htm#diff

[Chris2087]

http://www.6mmbr.com/223Rem.html

This is a very good write up on the .223 and the 5.56

Chris

[bjl913]

if i remember correctly, external dimensions of the cases is exactly the same, but 5.56 casings are slightly thicker, mostly through the shoulder, causing them to have less internal volume, therefore developing more chamber pressures with the same ammount of powder. if your barrel says 5.56, your good to go for both rounds, if it says .223, only shoot .223!