Since you've tightened all the nuts and bolts, switch scopes and try some factory ammo. Also, ck to see that the barrel is in fact floated. I do not own a CZ, but what I hear locally is that they are very good in the accuracy dept. In a box of Win 180 power points, I found app. 80% had <.003 RO. You can actually see .004 and greater as the tips will wiggle as you roll them on a level surface. So, disgard any you can see wiggle, or best yet use a concentricity gauge if you have one. IMO.
art
