I posted this on a discussion on bowlingchat but the site is down at this time so I will post it in a separate forum on here and in a separate forum on BC later when it is available.

While playing with the trial version of Blueprint software I found an interesting location for adding a weight hole the greatly increases the dynamics of the ball similar in effect as a p3/p4 weight hole.

This works on symmetric or asymmetric bowling balls where the PIN IS EVEN WITH OR ABOVE THE FINGERS. Figure that should be highlighted lol.

I will up load the pics on here so you can see the numbers and how they change based on first the ball being undrilled, then drilled, then with a weight hole on the bowlers PAP, then 2.5" down the val, then with the weight hole in the p4 positions and then the interesting locations I found.

These two locations are, on the bowlers center grip of their span, and 1/2" to 3/4" down the center grip line of their span towards the thumb. How far down you can go will depend on the bowlers span. In the example I used, the span is 4 3/4" and the maximum I can go down the span is 3/4". After that the weight hole intersects the thumb hole.

All weight holes used in the given examples are 1" by 3.5" with 0 pitches. The great thing I have found with this is that it gives the driller a chance to add a large flare increasing weight hole to to the bowling ball with literally no effect on the bowling balls side weight, and little to no effect on the bowling balls finger or thumb weight.

Typically for pin up drillings if you want to add a flare increasing weight hole to the ball you have to have a longer pin ball to do so. Because the p3 or p4 weight hole is going to be well below the center grip line and on the positive side of the ball. That requires a decent amount of side weight and or thumb weight in order to keep the static weights legal. Depending on the bowlers span this can be hard to do with a ball that has a 2" to 3" pin in most cases.

Pic03 is the x-hole on the pap
Pic04 is the x-hole 2.5" down the VAL

PIC07 is the weight hole down the bowlers center grip line 3/4"

This makes perfect sense to me. The drilling angles for the bowler you are using, places the mb close to the thumb hole. Add another hole near the thumb, and you are going to increase diff by a good deal. Did you plug in a "double-thumb" x hole to compare the results? And if you want some CRAZY numbers, I'll message you some of the things I came up with lol.

Perhaps you would get similar or better results with a hole immediately below the thumb, provided you can keep the statics legal for fingerweight. This way "feel" wouldn't be an issue.

The weight hole is on the bowlers center grip of their span. The hole below that is the thumb. Going with a weight hole below the thumb would cause it to flare over the weight hole for nearly everyone as best I can tell.

The key factor is pin location. If the pin is below the fingers the effects are less desired. The pin even with or above the fingers have much much better results. On shorter spans your not able to move the weight hole down due to the x-hole and thumb hole intersecting. You can do two different options.

1. Make the weight 1 1/8" which really bumps up the numbers while leaving the weight hole in the span.
2. With shorter spans it is much easier to move the pin higher above the fingers and this will also create an increase in numbers because the x-hole takes out more of the core.


I will post the results of the pin down drilling and how it does not have the same effects shortly.

I remember seeing a post a long time ago, Mo using a hole like this for a few guys . It was a "Mo-hole".

Mo-hole is hilarious. He didn't say much on his site about it. I assume he is busy.

more pics of pin down changes