I've seen several hand made ball molds and the balls they cast. The one thing common to all of them is that the balls were all visibly out of round.
I have also experimented with faulty balls I've cast, ones with visible pock marks, wrinkles, and that are underweight. What is "funny" about those is that they seem to shoot as well as "perfect" balls. So when I'm casting with a bag mold I just use the bad ones alongside the good ones.
With one of my multi cavity molds and my electric pot, I will put the bad balls back and remelt 'em 'cause it's not so much work.
Three Hawks