If want to believe that go ahead. A Handi shoots best when it's filthy. Since we no longer use corrosive primers or powder cleaning is a waste of time.
Your Handi may shoot best when "filthy"..but mine don't...what to know why? Cause mine are lapped very smooth..and I guarantee you they shoot exceptionally well.
If you don't want to believe that pitting and barrel corrosion can happen under copper,lead,Black/Blue Moly or Lubalox in barrel..I feel sorry for you..because it happens every day to millions of rifle bores..
Did it ever occur to you..and some others..the reason your Handi shoots best when"filthy" is because of all of the irregularities and crevices being filled in with (God knows what in yours at least) lead/carbon/copper/bullet coatings...?
Probably not..
Mac