info on CZ site...
I just remembered that I was thinking of ordering a new CZ in .223 a while back (I am quite fond of my rimfire CZ rifles), so I went to their site, saw that they offered both a 1:9 and 1:12 model, with the following comment:
The 527 Varmint models in .223 Rem feature a 1:9" twist barrel which is able to stabilize bullets up to 70 grains, while the 527 American models in .223 feature a 1:12" twist more suitable to bullet weights 55 grains and less.
I think I am good to go with whatever I can lay my hands on .