When I was at the factory for revolver armorers school back in the mid to late 80's ( 2 different times), I observed a couple of barrels of Breakfree within the factory.
S&W would not endorse Breakfree, but they were using it. Today's use, I have no idea.
A S&W revolver only needs about 6 drops of oil. Two on the barrel of the yoke, and one on each pivot point.
I don't use even
that much (and then again, maybe I'm doing it all wrong) to lube a revolver (Smith or my Taurus 66). After stripping down to the frame and cleaning, I put a drop on the pivot point of the trigger, message it in with my finger then run that finger over the trigger where it contacts the frame, also the engagement points with the hammer, sear, hammer to frame engagement points (all with the same drop of oil). When my finger gets dry, I just put another drop on and continue. I got into that regiment when I lived down in Arizona (the dusty desert ya know) and have just stuck with it. Oil will attract dust, dirt, sand, so I learned to use the least amount of oil possible, but still enough to do what's needed. I've seen guys at IPSC matched (late 70's thru the 80's) cock their hammer, then take a plastic oil bottle and insert into the action, then give it a good squeeze, shake their gun a couple of times, wipe it down with a clean dry cloth and call it good. I never did feel good about doing that myself though, what with the constant chance of a dust storm, or a lone dust devil coming thru ya know. YMMV though, just the way
I do things. Have a good one.
My literature that came with my NEW 686-6 said to first clean all the
preservative off the gun, bore, cylinder and I think the internal lockwork (but I might be mistaken there and mis-read it) before firing it the first time.