Searched and didn't find an answer to this question. Took the NRA pistol course and just purchased first gun, M&P9. Haven't even had a chance to get to the range with it yet but have been reading whatever I can. Regarding cleaning I've seen several comments that when cleaning bore, brush/patches/etc. should only be run through in the direction the bullet travels, never from muzzle end. True? If yes, why? I bought the standard Hoppes pistol cleaning kit to get started. Any and all advice and comments welcome.