Expert: - 7/29/2009

Question
hi. i want to know about functional of major pin (pin), center of gravity (cg), mass bias (mb) and Positive Axis Point (PAP) to bowling ball reaction effect when we drill the ball

what is different between short pin (pin in) and long pin distance (pin out) to bowling ball reaction and drilling pattern?

Answer
Wadud,
Position of the major pin (top of the weightblock) determines how much flare you will get out of a ball. CG is an identifier of the heaviest point on the ball, a sign of imbalance potential, and potential to use a weighthole. MB is the secondary locator pin, identifying where the side of the core is positioned.

PAP is Positive Axis Point, a coordinate identifying the axis of your ball's first rotations. How a bowler rolls a ball dictates what a ball will/can do. If the the PAP is not used as the basis for the bowler's ball layout, the driller is just guessing. Guessing isn't good.

Short pin (pin in) and long pin (pin out) difference, obviously is distance from pin to cg marking. But a short pin should be used for some layouts and long pin for others. By positioning the pin and heaviest point on the ball (CG), you can create different dynamics. Shifting weight away from grip center can create a dynamic (with a weigh hole) where a significant effect can be created. All the ball manufacturers have drill sheets on their websites. Take a look at them. They explain what moving various elements of their balls will do.

Thanks for your question. Welcome back. Bowl well.