I finally got out today to try some different .22s in my 617. I redid the trigger and got it down to 6.5 lbs Double Action by installing an APEX Hammer. Mainspring stayed the same but I put in an 11 lb rebound spring.
The springs that came with the Apex were not strong enough to insure trigger reset.
I had 100% reliability with any CCI ammo including Blazer, Standard Velocity and Mini Mags. The gun also like Federal Automatch. Good thing because I have 15 packs of 325.
The only ammo that gave me problems was Aguilla. Out of 100 rounds I had two that would not go off on the first strike. Not bad bu t that eliminates them from my Match Ammo.