Let me preface by saying I'm a tinkerer. I just can't seem to leave one of my guns alone.
This is my Old and Faithful S&W Model 617. I shoot this for Steel Challenge Rimfire Pistol Open on occasion when I don't want to shoot my Black Mamba. After doing a trigger job and re-cutting the forcing cone to 11 degrees I've eliminated all lead spitting and have improved accuracy.
I replaced the hammer with a new Apex Tactical Mass Drive Hammer. It's advertised to give a 6.5 pound trigger that is just about 100% reliable. Mine is set at 7.5 pounds to be sure that it works with the variety of ammo I have in stock. The best is Federal High Velocity 40 grain. It's rated at just over 1200 fps and although it is lead ammo it is very clean. I can shoot an entire SC without having to clean the cylinders.
I've also had very good luck with Federal BYOB 36 grain plated, CCI Blazer and Wolf Match Extra. The gun does not like Eley giving me about 95% reliability. Not good enough for match ammo. Aguila SE is also only 95% reliable.
The gun also boasts a C-More Railway red dot sight with a 12 MOA dot. Even with that large dot I can manage 1 - 1.5 inch groups from a rest at 25 yards. When shooting the revolver I hardly ever miss a target. My speed is just slower than with the autos but since I'm not missing, my times are faster.