RE: cleaning with brush?
Its overkill to remove the brush at the muzzle. It would probably be the best thing to do, to protech the edges of the muzzle. But way too tedious for me. I try to limit my brush use. And use brass jags with semi abrasive cleaners like JB bore, and when I get to the end of my stroke,after scrubbing, I remove the jag and pull my rod back thru.