I went to the Holt Road/Minnesota Road armory gun show today. Right n the second room was a guy selling AR's for $499. It was a small brand BUT noticed they were in .223 NOT 5.56. Watch what you buy. They are NOT the same.
I'd bet you anything that the chamber is cut 5.56. I don't know of any ar manufacturers that put a 223 chamber in their rifle. Colt ar's have 223 on the barrel and 5.56 on the lower. Or vice versa
Unless I'm mistaken, the barrel is the critical part, in that it has to withstand max loads by either .223 or 5.56. I doubt there's a barrel maker out there who doesn't plan for the worst-case scenario, as that's simply asking for a lawsuit. They have to assume someone will load 5.56 into a .223, or put a hand-loaded max load into the barrel.
Most of the rest of an AR has already been made out of resin on a 3D printer and has been shown capable of handling common ammo, so as long as your barrel is good and the other parts are spec, you should be good to go.
That being said, I still hold to the notion that if your life depends on it, you buy the best model available and take good care of it. I paid $175 in 1992 for a pair of Vasque Sundowner boots, and they're still going strong!
I'd bet you anything that the chamber is cut 5.56. I don't know of any ar manufacturers that put a 223 chamber in their rifle. Colt ar's have 223 on the barrel and 5.56 on the lower. Or vice versa
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Makes absolutely no matter what is on the lower. It can say 20mm vulcan for all anyone cares. Its what the BARREL is marked that determines what can be fired. My DPMS SS Fluted Target barrel is marked .223 Rem.