I just did this myself. Take barrel out, clean/polish breach end of barrel real good, apply divers silicone to it. With bottle off and barrel out you can get Q-tips and clean out breach ID and O-rings and apply silicone there as well. It took me several Q-tips to get the black gunk out. My breach now slides smooth as glass.
Somthing that works well for the inside of the frame tube itself, is to spray a small shot of dry graphite in it. The silicone on the bbl. where the hamer rides, and the dry graphite in the frame where it touches together will really maker her quick and smooth!
But first, as said, polish the breach end of the bbl. where the hammer rides.