Freedom, it is generally recommended that a barrel that is stamped .223 should only run .223 for safety and warranty purposes and not 5.56.

Freedom - The pressures that a 5.56 NATO cartridge can generate are too high for the .223 Rem chamber (up to 11% higher!) and firing 5.56 in a barrel rated for 223 can result in a fast and dangerous pressure spike. Again, firing lower pressure .223 Rem. ammo from a 5.56 NATO chamber is no issue, but firing higher pressure 5.56 NATO ammo from a .223 Rem. chambered firearm is a true safety hazard. The only exception is a barrel chambered in 223 Wylde. The .223 Wylde is a hybrid .223/5.56 chamber designed by Bill Wylde to yield the accuracy advantages of the match .223 Remington commercial chambering, but without pressure or reliability failures when using high velocity 5.56 NATO spec ammunition. The 223 Wylde barrels can safely handle the pressure from 5.56 ammunition. shootingillustrated.com/articles/2018/7/28/556-nato-vs-223-rem-whats-the-difference/