I use Break free clp spray it all down and go get a soda then come back and wipe it off repeat as needed you may need a brush on stubborn deposits inside the cylinder I pack in a cotton ball saturated with clp and let it sit

Kano Kroil is what I've used for many years.

Hi Adam, CLP is the way to go.

I spray down my Taurus 651SS with some MPro7 cleaner and scrub a bit with a nylon brush and let it sit for awhile. Then spray some more and wipe it all off. It works pretty well except where the barrel meets the cylinder. You'll have to do a lot more scrubbing to get that clean.
When you're all done cleaning, give it a good wipe down with some oil and it should look good as new.