Well it was sugested to get a Big 45 pad and wrap some strands around a brush. This will shave the lumps down so you don,t have as much to dissolve. Using a piece of Chore Boy would be my 2nd idea to speed things up getting the lumps out. It will not dissolve using it with copper solvent. Besides whats the difference if it does leave some green with whats dissolved from the bore. It will wipe out on the patch. Using either on a brush, especially a nylon one, will help getting things out like the patch of lead. Plus either won,t hurt the bore.
I received the Big 45 Frontier Metal Cleaner I ordered and started using it wrapped around a bronze bore brush. After making 1,700 strokes through the bore with this stuff wetted with Bore Tech CU+2, I inspected the bore with my borescope. I can see I'm making some progress, but I don't think the Big 45 is working any faster than the nylon bore brush. I think the fouling in my barrel is so old, so hard, so vitrified and baked on to the barrel steel that removing this stuff is more a process of the chemical reaction with the CU+2 than the mechanical method used. This rifle was probably fed a steady diet of ammo that used potassium chlorate primers which left a residue of potassium chloride salt in the bore. I do know that salt has been used for centuries to glaze earthen stoneware under high temperatures to form a very hard surface. The potassium chloride salt residue has likely done the same in my barrel due to repeated firings over its lifetime and encapsulated the copper and other stuff. I'm no chemist, but it may have reacted with the copper to create some 'witches brew' compound.
Based on my findings, I resumed my cleaning process using a nylon bore brush and made another 2,000 passes through the bore. The 'blue soup' that dripped out of the barrel into my catch pan was as dark blue (see picture) as what dripped out when using the Big 45 metal cleaner.
I've since made another 1,500 passes with a nylon bore brush and am still getting 'blue soup' out of the barrel, but it is starting to look a little less intense blue in color. At this point, I have made a total of 6,750 passes through the barrel with some kind of bore brush (bronze, nylon, Big 45) and still getting copper out. This is going to be a very, very, very long, tedious process, but with the pandemic in full swing, winter weather now here, and not much else to do, I'll just keep brushing and listen to Willie Nelson and Merle Haggard on the radio. The one positive observation is that as I get the fouling out I can see that the rifling in the barrel looks to be in fairly decent shape, although it is pitted.
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