Call CZ and complain.
When I bought a 455 and later a .22 LR conversion, the instructions said the headspace had to be checked and the barrel adjusted if necessary. I was ticked, but when I contacted CZ USA, they said not to worry, it would be fine. By the time they got back to me, I had already shot it.
I did have some feeding issues with the LR, which could probably have been fixed by shifting the mag well around a bit, but by that time I decided the switch-barrel concept was over-rated. I sold it and bought a 453 in LR.
