Won't harm the barrel a bit and unless you are trying for some serious 'get down there and knock something down' loads you won't see much difference in accuracy either. Even if you get a little leading prompt cleaning right after shooting takes care of that. More important is the size of the bullet you are shooting and your lube.
Good intentions will always be pleaded for any assumption of power. The Constitution was made to guard the people against the dangers of good intentions. There are men in all ages who mean to govern will, but they mean to govern. They promise to be good masters, but they mean to be masters.