Terminology

Span: The distance between the fingers and thumb used for the purpose of gripping the ball. 

Hole Size and Shape: The internal measurements and shape of the hole or insert used. 

Pitch: The angle at which a hole is drilled in the ball. Pitch is defined as it relates to the center of the bowling ball. (A hole with “Zero” pitch would be any drilled hole where the center of the hole, if extended, would pass through the center of the ball.)

    

The measurement of pitch is the distance that the center of the hole deviates from the center of the ball in a specific direction. 

The Pitches are based off the X and Y axis of each individual hole, Y being parallel to the centerline.

 

Forward Pitch: Term given to any hole where the center of the hole extended would pass above the center of the ball.  

 Reverse Pitch: Term given to any hole where the center of the hole extended would pass below the center of the ball.

When viewing the back of your hand, forward pitch is towards the inside of your hand and reverse pitch is outside of your hand.

Side Pitch:  The right and left components of pitch in which the center of the drilled hole passes to the right or left of the center of the ball. Parallel lateral pitches are not the same as zero lateral pitch in both fingers!  

 

Why we do that?  

The proper fit will allow the customer to use less effort to grip the ball, allowing them to have a more relaxed arm swing and release. To accomplish this there is a relationship between span, pitch, hole size and shape.  

 - 50% Span (distance between the holes) 

- 30% Pitch (angles of the holes) 

- 20% Hole size and shape