I have an Orca printed in Polymaker PA6-CF. I've definitely noticed some accuracy shifting just like Tim demonstrated in his Orca accuracy testing video. I also have Ivan's SF5 (which features a similar clamshell barrel mounting solution) printed from the same batch of PA6-CF, and it shoots way more consistently, with little to no noticeable shifting even after 400 rounds just today. Though perhaps that is partly due to it being chambered in a less powerful pistol cartridge (9mm) and having a much shorter barrel that may not wobble as aggressively after firing. Other than those things, the only main difference in the setup is that I did apply silicone RTV to the barrel mounts of the SF5.
I did print the barrel mounts in PA6-CF as well, though I think I recall the Orca instructions recommending a glass fiber nylon filament over the carbon fiber. Could it help to reprint the mounts in this other filament?
