I can sometimes go hundreds of shots with no indication of leading and good accuracy then with the same load, alloy, lube and air temperature -- Bam, accuracy drops off and leading can be felt on a bore brush or a tight patch as well as clearly seen with a bore scope.
Bronze bore brushes, steel wool, lead out cloth, bronze cleaning pad strands are all useful in scraping it off. With at least some kinds of lead deposited in a bore a penetrating oil can soak in under the lead and weaken the bond -- or so I have been told and believe I have seen.
If leading can be removed with penetrating oil it would be less work and easier on the bore. I have tried this many times. Sometimes it seems to work sometimes not. Several of them work well on rusted threads. Not so sure about removing lead.
I am a sucker for elixirs and have a collection. Kroil, Ballistol, Fabulous PB blaster, Marvel Mystery Oil all claim to be "penetrating". I also must have most of the "bore cleaners know to civilization. Still I am not sure which work best , or at all on leading.
Does anybody know of a serious comparison study to see which are best? If not, what is your experience?