RESULTS. Here are my results after shooting over 200 hard cast alloy bullets through my JM625 over two days. 100 rounds per day and thurough cleaning after each day:

Hoppes #9 (you guessed it!) with a brass bore scrubber cleaned anything and everything from the bore. First I soaked the bore with Hoppes # 9 -not "Rem Oil" nor "Break Free CLP".... nor anything else. Just Hoppes #9. Left it soak. Scrubbed the **** out of it with the bore scrubber. Soaked it again...repeat.

What I did notice inspecting the barrel from both ends with a bore light was after the 3rd scrubbing was that while the barrel and rifling itself were virgin clean, the chamber end where there the bore is smooth for a fraction of an inch before the rifling starts -that spot there, directly where the bore meets the cylinder chambers, under the bore light it had what appeared to be "tiny little pebbles" LEAD! This was just a function of driving the bore scrubber from the muzzle. So I managed to scrub from the chamber end with the bore scrubber attachment, leaving it to sit in the chamber end of the bore after pouring a few drops of Hoppes # 9 then directly using my fingers to use the brass scrubber attachment to reach around inside the end of the bore it to hit those hard to reach places and after about 10 minutes there wasn't a speck of lead anywhere.

So. Cleaning after shooting Lead or Hard Cast Lead Alloy is a pain in the ***. But in my experience, my JM625 shoots lead beautifully and its just a matter of developing a good cleaning procedure.

Next, I am going to use a .50 Caliber brass scrubber through the muzzle, and weld a .45 scrubber to an Allen tool to easier scrub into the Chamber end of the bore and get those spots where I cant apply pressure from a scrubber through the muzzle.