Originally Posted by
darkker
The "issue" with cleaning wear, isn't from the brush so much. It's from people grinding away on the throat area with the steel rod. You don't have to "wear away" the rifling. You just have to knock-down the edges, thereby causing gas by-passing; and further accelerating the wear from the combustion gasses.
The hard metal particles in the fouling, typically from the primer but also the Tin/Bismuth in "cleaner" powders, or the hard carbon which is a side effect of Coated extruded(Extreme) powders. Those are the large wear components.