I use the .224 bullets in my CZ527fs, but this barrel has quite a bit of choke in the last inch or so. I probably could shoot .223s, but it shoots 40 grainers and LilGun so well, I have no reason to experiment further.

As long as the case neck can expand in the chamber sufficiently for the bullet to be freely released, the difference of 0.001" in groove diameter doesn't matter. You can safely shoot .224" bullets in a barrel with .223" grooves, BUT it must come out of the case easily. Try dropping a .224" bullet into a fired case before you resize it. If it goes in easily, without having to be forced, you can use it!