Totally agree. When I was using water, I filled it to the tip....let it seep past the ball and kept filling, then I used the bore cleaner. I had water squirting out the ignition hole, much like a drinking fountain however, I could get it to go maybe 10' in the air. So much of any loose stuff that was behind the ball might also be rinsed out. It washed the sides but I don't think it removed any rough material.
The ball seems to seal at (let's jut say) 15" inside the bore. When the ball gets pushed back to (let's say) 25" down the bore, you can easily see a gap at the top.... so the idea of the ball being deformed has been on my mind the entire time. Either that or the bore is very uneven. Looking down with flashlight, I don't see any obvious deformations of the bore however, that is a very casual comment as I've nothing to really compare it with. Still, going by the seat of the pants, I'm leaning to the ball being deformed.
Looking at the ball down the bore, It has me thinking these are maybe painted. I see some discoloration spots on it but instead of looking discolored, they look shiny like the paint has flaked off.