Hello! and Welcome to our Forum. Always nice to meet new folks. I only own a 550 UCS so there isn't much I can do to answer your questions, but I did want you to know someone had seen it and that someone else may be able to answer your question, at least differently than the answer I am going to give you now.
Try calling CZ-USA and talk to one of the blacksmith's there, the CZ-USA President and at least one other Senior Management person are not just hunters, they are BIG as in huge critters and if you think hearing a click is less than desirable they trust me those folks Really don't want to have to deal with any extraneous noises when they are looking at a couple tons of critter. or a smaller one that moves so fast you had best hope you wearing track shoes and can shoot backwards while you run.
, Not that I would like to be staring down a Buck or Mose, or for that matter a bear ANY bear, unless it was either Smoky or Yogi.
So I would think that someone (one of the Blacksmith's)there would have an idea how to address your problem. If that fails, which would suprise me a little, then call CZCustom and talk to those folks, I think they are all some sort of Wizard's or close to it when it comes to firearms and I' think I remember seeing they work on longguns also.
I'm sorry but thats the best I can do to help.