My revolvers always get a few deposits of lead in the forcing cone/leade area. Heavy or light loads, doesn't seem to matter, hard alloy or soft, they always get a bit of very hard deposits that are hard to remove. Semi-autos and lead boolits don't do this, they can lead the leade a bit, but the deposits are always easy to remove with a bore brush and a couple of strokes. But revolvers.......... Different animal, usually the cylinder throats get the same hard lead deposits, centerfires anyway, and after a couple of cylinders, the barrel leade is just as leadded as it was before cleaning.
On the bright side, this leadding only goes so far, then keeps an even keel, no matter how many rounds you put down the pipe. Some ammo fouls less, some ammo fouls more, I haven't spent much time tracking how copper washed bullets compare to plain lead in the revolver, but I would think the copper ones run a little cleaner. I have found any ammo that runs cleaner as far as leadding is concerned, it will actually clean the bore of previous deposits left by dirtier ammo. Shooting a half dozen jacketed rounds down the barrel pretty much cleans out any lead deposits. If you have a convertable, run a cylinder of .22 mags through it, this will clear most of your leadding out.
Interestingly, leadding in the leade and throats in a revolver doesn't impair the accuracy, I have a Security Six that shoots 1" to 1 1/2" groups at 25 yards, clean bore or fouled bore, the groups are uneffected. The thing that is affected by cylinder and leade leadding is velocity, my Sec-Six shoots about 70 fps faster after the throats and leade have been fouled by a couple of cylinders after having been cleaned. So, long story short, my revolver shoots better with a fouled bore.
What's the moral of the story? I think scrubbing down to bare metal in a lead shootin hand rig might just be over rated. I do know you can damage a gun by over / improper cleaning technique. So, I have trained myself to just not worry about it. I do clean and oil my guns meticulously, however, forcing cone fouling on a lead shooting revolver doesn't seem to hurt anything, and I just live with it.