as expected, the "what's the best bp cleaner" saga will continue forever and ever, in an endless loop that starts with water-only people and ends with the space-age-gobble-dee-gook people, and then 'round back again. i've been Extensively through the gamut of chemical concoctions and procedures and have pretty much come back to how it was done back in the 18th century, and even before then.
i will not use hot water as that only preps the steel to accept chemicals into it's nooks and crannies. better to take time to allow tepid water to do its most natural thing - dissolve bp residue.
i will not use soap because it adds rather than takes away. i've totally given up on LVL and others because of the residue they leave. i've witnessed this with all my black powder powered guns, from muzzleloader to cartridge. it made a mess of my revolvers, to the point of not being able to chamber cartridges. anyone need 2/3rds gallon or original formula lehigh valley? please be my guest!
the only addition to water that i now use is ballistol, which is a water soluble mineral oil.
the only thing i'll do to any barrel (inside and out), lock, action, gun metal, after the bp cleaning process is wipe down with any light oil, for metal preservation.
a few dayze ago i pulled out the .40, .54 and .62 for a check after all being dormant from late fall 'til now (gettin antsy for spring shootin). they were all cared for last year via the methods previously described. the bores and metal are all perfectly clean.