Question on drilling patterns

[Bendial]

Hi Guys,

Pretty new to bowling so pardon the ignorance here, but I've noticed in looking at a lot of drilled balls some players have an extra big hole to the right (if they are right hander) of the hand position. What is that hole for? Here is an example:

http://c3421146.r46.cf0.rackcdn.com/video-balls/storm/manic/tony-1000.jpg

[J Anderson]

The extra hole in the picture has one of two possible uses. The first is to change the dynamics of the ball, usually to give the ball more flare potential. In rare instances its used to reduce the flare when a ball is too aggressive.

The other purpose is to bring the ball back into USBC compliance if the static weight is off after the ball is drilled.

Also called a balance hole or a 'get back' hole.

[eugene02]

that is also known as the balance hole.. as what John has said.. it's to create more hook on the ball or simply to get the ball legal in compliance to USBC status..