Well, Myth Busters says.... "BUSTED".
But there is a cosmetic improvement .
Tethered to 800psi HPA didn't help either.
Breach and TP hole/burr it is... when I get the time. I did push a couple different pellets through the barrel, still mounted, and the softer ones (JBB RS and Daisy) had visible shear deformation on the heads (skirts were slightly knackerd, but it took considerable effort to get pellet moving with ultra thick weed wacker line).