Recently I bought a fully plugged AMF Heist Pearl for $25 shipped (from iamone78 here -- thanks for a heckuva deal!). As you can see from the pic, the span before plugging was close to mine and the layout was similar to what's required for a bowler with my PAP on the MOtion hole. I've been curious about this layout and figured this ball was a perfect guinea pig.

Per instructions, my driller marked the spot with tape and I threw the ball down the lane while he watched. Sure enough I was tracking over the spot. So he took the ball away, moved the hole slightly, and brought it back drilled.

I wish I had a video to demonstrate the difference. The Heist Pearl was a very limited edition ball - actually the Heists were the first balls produced out of 900G's San Antonio plant - and it was known for it's low RG core but super smooth weaker cover. This lent itself to a very predictable reaction across all lane conditions, even for a Pearl. This is always how I imagined the Seismic Aftermath Pearl to be.

Anyway, before the MOhole I was playing the same line as my Brunswick Ringer, currently one of my favorite balls. The ball motion was very similar - the classic Brunswick roll. After the hole, I was forced to move 2 boards left of the Ringer and had a good 5 more boards of recovery to the right if I threw it out. As the lanes opened up I ended up 4 boards left. When the ball hit friction you could see the revs, but with that weaker cover it didn't jump. The continuity through the pin deck was impressive. And it was carrying the corners better than before the hole. Frankly, after the MOhole it was reminding me more of my Brunswick Aura than my Ringer. I'll have to compare them next time. But the MOhole unleashed the backend on this ball.

I can't imagine what this would be like for me on a ball with similar core specs and a stronger cover. I'm sold!

The sideways was not sideways as they described the reaction when it was released.  I think that one would be good to try the MOtion hole. Had mine not cracked I would try it.

So dumb question.  My driller has never told me my pap.  If my track is 2" from middle finger and 1" from thumb would my pap be less or greater than 5"?

They don't really design balls that do this for low tilt, speed dominant bowlers...  This layout gives those bowlers something they couldn't create before.

This describes my style to a tee.  Can you recommend a ball that would be a good choice for this style and that is a good candidate for the MO hole?  Bowling on typical THS  on synthetics.

Maybe my Torrid...

Worked-out well on my friend's Torrid Elite with only a 5/8in MoHole. I tried it and thought it performed much better this way before the hole was added. Of course his span, pitches, PAP is close to mine. He now has a Torrid Affair with another 5/8in MoHole and is again equally pleased.

I'd like to expand a touch on my comments before.

I was lucky enough to have some old time drillers give me some weightholes past the balls north(top) and south border(bottom) which is at 6 3/4 from the grip center.

Weightholes were often by these old timers put at 7 inches from the grip center or 9 inches from the grip center.  Both in this lefty's case at a 8:30 direction from the grip center(if I had been righty it would have been at a 3:30 direction).

These drillings past the North South equator of the ball seemed to add mostly backend and reduce midlane.  The Gravity balance system would say they were raising finger, raising top and reducing side.  The nick the core people would say they are increasing differential(even if the core is not contacted I believe.) The Brunswick people I believe are saying they are increasing flare separation and the bigger the size of the drill bit the bigger the increase in flare separation(I hope I have that right!).  I don't know why but I think they are right, but I don't know their reasons.  The nick the core people I hope can help me out here too!

So be it.  They reacted, and more in the back.

Today also we have from MO, new weightholes that can increase rev up(p3) and really increase rev UP(P4).  Gravity Balance (from Lane 1) people would say they are decreasing top weight faster than side for every inch(or unit) of travel of the drill bit, and often adding some finger.  I thinking of the gravity balance system can see how reduced top can increase early rev up and more finger can add some backend.  I'll leave the explanation of how midlane and backend reaction are increased in these cases of P3 and P4 to the Nick the core and Brunswick people to point us in the right direction.

A variation on all these themes is angled away from weightholes and I don't know how the Nick the core people explain the increase in reaction(mostly midlane it seems) or the Brunswick drill weightholes off of the PAP people explain the increase in reaction if this is done on the PAP but it seems to work.  Naturally the Gravity balance people have an explanation, less side taken out and more top leaves the ball more dynamic).

Anyway I extrapolated the idea of the 9 inch on my 8:30 direction a bunch of years ago and put a weighthole 10 inches from my grip center on a nice oil cheating Jade Quantum Proactive, and it increased reaction in the back about two inches.  It did not nick the core, but it sure was off the PAP(for the Brunswick people).  Again the Gravity balance people would say, more TOP, near similar side and added some finger.

I have compared the 10 inch Motion Hole location to the old time 10 inches from grip center and noticed in my case they are about 3 inches apart.  The old 10 inch hole is straight down from the new motion hole.  As a Gravity Balance person I would say the resulting holes both raise top weight, both leave side about the same(for me), and the old style hole increases finger the new "MOtion" hole increases thumb.

As to what the nick the core people would say I think I have an idea, what the Brunswick people would say I think I have an idea also.

So the 3 burning questions I have are:

1.  For the nick the core people, how come weightholes that never touch the core can dramatically increase reaction?
2.  For the Brunswick people when do bigger weightholes increase reaction more(I do think I can anticipate the answer, but I would like to hear it anyway.  (A related question is: if a hole is very wide diameter and very shallow, will it have a greater effect on reaction than a smaller weighthole drilled deeper that has the same effect on statics(assumption both holes drilled the same distance from the PAP).
3.  For both the Nick the core people and the Brunswick people, why do angled weightholes seem to increase reaction(a) for the nick the core people, even though they have less probability of nicking core?  (b) for the Brunswick people, even if they have the same hole diameter size and are in the same place in relation to the PAP.

For those just enjoying the "new" weightholes, Viva la difference!  I think you are right, there is more reaction later and downlane!  Oui Oui!

Regards,

Luckylefty

Well I have two nights with my freshly mo holed Freight Train, and so far I can tell that it woke up the ball on the back.  I never liked this ball much before as it seemed very condition specific, but now it will hold pulled shots better and recover better when thrown out too far.  I have the surface at 3000 with polish.  So if this mo hole has helped this ball out, can't wait to try it out on a nice sym pearl!

Lucky,

I don't know if this answer will help, but I will give it a try.  When I want to drill a weight hole only to make the ball statically legal, I typically go with a larger diameter (7/8" or 1"), and keep them shallow, as to not remove any mass from the core.  If I want to enhance motion, I will drill the weight hole with a smaller diameter and a deeper depth, typically 3".

Another thing to keep in mind is that prior to drilling the MOtion hole, the fingers are drilled 3 to 3-1/2" deep.  The MOtion hole is drilled 4" deep.  At these depths, you are removing mass from the core, which is altering the position of the low RG, as well as changing the differential.