Can someone explain to me what a drilling on a ball means and what the ball will do if someone says it's drilled 50 x 4 x 40?  Or a drilling of 40 x 4.5 x 45?  Very confusing to me.

Maybe this will be of some use to you.

http://www.bowlersreference.com/Ball/Layout/Dual.htm

http://wiki.bowlingchat.net/wiki/images/c/cd/DualAngle.pdf

http://www.bowlingball.com/BowlVersity/how-to-layout-a-bowling-ball-dual-angle-layout-technique

Can someone explain to me what a drilling on a ball means and what the ball will do if someone says it's drilled 50 x 4 x 40?  Or a drilling of 40 x 4.5 x 45?  Very confusing to me.

Basic info


Dual Angle Info:
The Dual Angle Layout Technique is made up of three measurements:

1. The Drilling Angle: Which affects the length of the skid phase of the ball.
Higher angles = A Longer Skid phase.
Lower angles = The quicker the transition into the hook phase.

2. The Pin to Positive Axis Point (Pin-to-PAP) distance:
The Pin to PAP distance affects the amount of the flare.

3. The Vertical Axis Line (VAL) angle: Controls how long the ball remains in the hook phase.

Smaller Angles to the VAL lowers the RG, and increases the total differential of the ball. This results in the ball reving up faster and transitioning faster from the hook into the roll phase of the ball.

Larger Angles to the VAL raises the RG, and decreases the total differential of the ball. This results in the ball reving up slower and transitioning slower from the hook into the roll phase of the ball.