new guy needs clarification

[JY25]

Im new to rifles so I need some clarification. Is .223 and 5.56 nato the same? When shopping for uppers I see some say .223 others 5.56 nato. Can you shoot both thru the same barrel? Thanks in advance.

[5150Marcelo]

You can shoot 223 and 556 outta 556, but DO NOT shoot 556 outta 223.

[SoCalRandy]

Just make sure you buy an upper with a barrel chambered in 556 and you'll be fine.

[Crusader]

5.56 is slightly longer and loaded to a higher pressure than .223 is. A rifle chambered in 5.56 can safely shoot both.

A rifle chambered in .223 risks being overpressurized. It may not be too big of an issue, but I personally would not risk it.

[JY25]

Thanks for clearing that up. Now I know what to shop for.