Sometimes i think one would never have to clean the barrel; just keep shooting. The flame channel in the breech plug does need periodic cleaning. As Lemoyne suggested a 1/8" drill spun by hand now and again, works in the breech plug.

Don't buy into the malarky that BH isn't corrosive. The burnt residue of BH will absorb water, and will rust your barrel. To me it seems you could shoot a jillion shots at the range without cleaning the barrel, but when done shooting, whether you have made 1 shot, or 50 shots; cleaning the barrel is wise.