How do you determine pitch angles in a bowling ball?

[Hammer]

I have a 3/8 reverse pitch angle on my thumbhole. I want to have a new slug put in and change to a 1/4" forward pitch for more control on my ball at the release. How does a pro shop determine what pitch angles you should use for your thumb and finger holes?

[NewToBowling]

From what I've noticed they use a pitch chart to go off of. They test your flexibility and use the chart to figure it out. Of course with experience the chart becomes more of a baseline vs the standard I would think

[Hammer]

From doing research on my computer about how pitches are decided on there is more to it then meets the eye. Sometimes you just have to try different pitches for your thumb and fingers until you get one that feels comfortable and works with your kind of release. So it is something that we all have to find out what is best for us because everybody is different in the release and how their hands are made.

[fokai73]

you mean control the "timing" of the thumb exiting the ball at release ;)

(forward - later; reverse - earlier)

[bowl1820]

This will give you a basic idea of how a ball is fitted and the pitches etc. are determined:

The MoRich Fitting System
http://wiki.bowlingchat.net/wiki/images/2/26/MorichFitting.pdf

The thing to understand is this just gives you a starting point on fit, you don't necessarily get a perfect fit the first time.

Once you get your grip first fitted, you may have to make adjustments as you go along. Tweaking the pitches & span to more perfectly fit your particular grip characteristic's do to your actual flexibility and such.

There is a art to fitting, it not all just follow the check list.

[KYDave]

There is a art to fitting, it not all just follow the check list.

100%

The hard part is trying to explain how something feels. Being able to put your hand in the ball isn't all there is to it. I've made tweaks over time and have really noticed it getting more and more comfortable on my hand. It comes off clean without even thinking about it.

I like to reference this fitting guide from jayhawk. If you bowl enough your hand can tell you what it needs.

http://www.jayhawkbowling.com/Pro_s_Corner/Fitting_Tips/fitting.html