I don't own a .223, either. My Sako A1 is a super accurate rifle, but of course, varmint weight 24" barrel.
With 40gr. VLC's(obsolete Barnes)40gr. Varminators (Barnes HP) both 40gr. Plastic tips and all 52gr. and 53gr. HP's shoot sub 1/2" using a variety of powders.
I've never seen a more easy to find sub 1/2" rifle before. It rivals 6PPC's, but then, .222's still win the odd BR matches. It's best groups with match bullets have been sub .2" @ 100 meters.
Like yours Marrakai, it has a very tight chamber. It wears a 4200 Elite side focus. For a long time, it had wore a 4200 8-32 Elite, objective focus scope.
I think it's shy of 2,000rounds and still shoots bug holes.
I also have a .17Rem on a CZ 527 with a 25" Pac-Nor 3-groove bl. It is also a tack driver.