YES, CZ USA said YES it is fine to shot 5.56 NATO and . 223 MATCH ammo in the CZ 527. CZ rifles are built to CIP spec, which doesn't differentiate between . 223 and 5.56, it uses the higher pressure of the two and considers them one cartridge. I hope this helps!

Larry, for warranty and safety reasons, I would confirm this with CZ USA Customer Service at Toll Free: 1-800-955-4486 - Phone: (913) 321-1811 Extension : 4701

Yes sir. You are smart to ask first! Stay safe and happy plinking!

Yup, the 527 is one of a few rifles chambered in .223 that you can shoot 5.56 out of safely.