After having owned several CZ 75 pattern pistols, I found that all of them had a somewhat loose sear cage with some play, sometimes only sideways, sometimes fore and aft, and sometimes both. Only the Omega lacked this "feature".
It's no big deal with the standard long hammer hooks, as most of us probably won't even notice it.
If you have a trigger job done and are after a clean breaking trigger without hammer camming, the moving sear cage can get annoying. The competition hammers hooks are so shallow already, that hammer camming is almost eliminated.
However when I got my CZ 75 Shadow Line, I noticed a lot of fore and aft movement in the sear cage. Even with the Shadow-style hammer, camming was quite noticeable.
I tried shimming with steel inserts, it worked great but I didn't like to have to deal with additional parts when disassembling and cleaning.
Then I read about Schmekys longer No 19 pin and came to another solution:
Why not fill the empty space behind the sear cage with the pin?
It has to be filed flat on one side because of the sear cages angled rear side.
The looser the fit of the sear cage, the wider the pin has to be. It can be fitted exactly by filing that flat part. Usually I fit it so the safety shaft still has some resistance when pushing in the frame. This ensures that there is no play left.
This is what it looks like in my Shadow:
The pin alone
So far it works great, absolutely tight fit, zero movement.
However I was only able to make this modification in pistols with ambidextrous safeties, I don't know how well it would work with single sided safeties.
