For the past 20 or so years, every new rifle/barrel I have obtained I have hand lapped then hit it with around 50 strokes of JB for a nice polish. This eliminates burrs and high cuts left by most all manufacturers these days. Your high end barrel makers do this before sending a barrel out but your factories don't even come close to a clean polish on the barrels that factories of old did. These factories telling you to go through this break in crap is them telling you to do their job for them.