Recently I got my hands on a .22 cal Bone Collector Bull Whisper (BCBW for short). I found the gun to be pretty loud and have an extremely sharp recoil. So much so that I snapped the reticules on 2 scopes and sheared off the stop pins of two mounts. I tried the BKL 11mm to Weaver heavy duty rail and that would not stay put.
I was in and out of the gun several times trying to figure out other issues as well... grinding, scraping, during cocking, etc. After a good bit of work and a few turns with my Dremel tool, I got the action working pretty well, but the sharpness of the recoil was still an issue and any scope / mount was just not going to cut it.
(after talking to other BCBW owners, my experience seems to be the exception rather than the norm. I think that is important to mention)
Rather than call it a total loss, I took a good look at my CFX and noticed that the trigger was identical in form as well as the rest of the internal components. So I did a switch-a-roo, moving the SAT & and Gas ram to the CFX and the CFX trigger and spring components to the BCBW.
What I got was something very interesting. The BCBW now shot more quietly, with a much more gentle recoil, was really accurate, and more importantly, the scope was staying put.
The CFX has a smooth as glass cocking stroke and a much nicer trigger, it acts like a totally new gun. The loudness and the recoil increased significantly in the CFX, but it is much heavier than the BCBW and I believe it will handle things better.. Time will tell.
In the end, I went from a BCBW that was not usable, to a BCBW that was not only usable but a joy to shoot, and an improved (at least seemingly improved... I will do some chrony and shot tests today), CFX.
One thing is for sure, the new SAT trigger group, if we can get them as parts, can just drop in without any modifications to some of the gamo guns that have the plastic trigger.
I'll share more as I learn more.