Re: Copper, and more copper!!!!
I use the foaming copper removel products, with very good results and HALF the cleaning time.
As to lapping, by removing the microscopic 'burrs', the barrel induces less friction and theoretically will last LONGER due to lower heat cycling and friction.
Lapped barrels last longer and are easier to clean, a win-win.
You are what you do, when it counts.