Pop Quiz. What's the very first rubber to come in contact with the ball on any pinball machine? Unless you're talking about one of those weird games like Pro Football that launch the ball out between the flippers, the answer is: the shooter tip!
Replace your old, chopped up shooter tip with a shiny new silicone one. Your balls with thank us.
These are used in the majority of pinball machines ever made, but there are a few games that don't need 'em (like 90s era Bally/Williams games with the nylon tipped auto-plunger).