Well first off this clean barrel is a fallacy there are pours in the metal and what ever you use to preserve your gun from rust will still be in those pours in most cases, I have been experimenting with this problem since about 10 years before inlines were invented.
My best answer is if you use the right cleaner, preservative, and preservative remover and powder some guns will shoot in or close enough to the minute of angle group that it makes no practical difference.
I find that in my Triumph and my Endeavor that cleaning with Hoppes Elite cleaner using Blackhorn and BrichwoodCasey synthetic oil and removing it with alcohal gives me this answer. With my traditionals I use lye soap and boiling water to clean and synthetic oil to preserve and Pyrodex RS for powder. I remove the synthetic oil with alcohol and the scrub with hot water before loading for hunting this has worked well for me.
Last edited by lemoyne; 11-08-2012 at 06:36 AM.