Current Perspective on USBC Extra Hole,
Static Weight Rule Change

April 20, 2020                       Version 2

What I see so far with the new static weight rule and the elimination of extra holes:

Static Weights:  The new rule on static weight allowing 3 ounces of imbalance does not affect ball reaction, except with spare balls, where the addition of 3 ounces of negative weight may help the ball go straighter.  As I wrote in the May, 2009 issue of BTM, there is no difference from 1 ounce to 3 ounces of imbalance in ball motion with new modern equipment having powerful weight blocks.  This makes it much easier to do layouts on balls with asymmetrical weight blocks where the mb (psa) is positioned to the right or left significantly.  It also saves a lot of time weighing balls and reduces the need for pin-out or pin-in balls whether they have asymmetrical or symmetrical weight blocks.  It is nice to not have to drill an extra hole for static weight purposes.  This part of the rule change is good!

Extra Holes:  It saves a lot of time not having to drill extra holes, but greatly reduced the ability to fine tune balls with symmetrical weight blocks.  The D’Terminator was used to spin balls after drilling, before and after the drilling of an extra hole, and one could easily see the change ball reaction.  Most holes we drilled were under 3/4 inch.  You could change the drilling angle 15 to 20 degree’s with a 3 to 3.5 inch hole, giving most bowlers the same advantage with these symmetrical weight block balls as they would have with an asymmetrical one.  We could watch bowlers and make a decision to make a ball stronger or weaker.

We still drill a few extra holes to improve performance, soon to be plugged, however with material much lighter than what the weight block is made of.  With smaller holes, you cannot make a symmetrical ball stronger than an asymmetrical one from what I can see.   The 3 ounce static weight rule has worked out quite well, allowing us to layout any asymmetrical ball without a problem,  Before that, an extra hole was required on many layouts to get us within the one ounce specification.

No-thumbers/two-handers do not seem to have any reduced performance without extra holes in asymmetrical equipment but I am still drilling extra holes with some layouts in symmetrical weight block balls.  These will be plugged by August 1, 2020, but the much lighter plug density will still increase performance.  If they use their thumb for spares, they will have to have a dedicated ball.  It does eliminate the ability to drill a ball with three finger holes, and the mark on the griping side of the fingers eliminates them throwing it the other way.

Spare shooting, where a person would take a finger out of one of the holes (usually the big finger) is now illegal, so they might just barely tip it in the top of the hole.  I’m not sure about the legality here.

Here are some notes on what I see so far:

  1. Eliminating extra holes makes it easier for Pro-Shops, but reduces choices for bowlers.  There are still so many ways around this, including the drilling an extra hole deep into the weight block and using plug (which is a much lower density-especially plug that hardens in 15 minutes) to fill the hole.  Customers, however, would pay a high price to have this done.
  2. This rule will have a lesser effect on top bowlers but will hurt the middle and better bowlers, the heart of bowling. .
  3. The PSO’s still have the responsibility to balance balls and make sure they are legal, although most anything will pass now.  I guess the scale companies are basically out of business!  We seldom have to weigh a ball now.
  4. Symmetrical Weight Block Balls: Extra holes were used to fine tune the ball reaction and match it to the bowler to adjust ball motion.  Plugging these holes may change your ball reaction.
  5. Asymmetrical balls: An extra hole was usually needed just to balance static weights, which allows PSO’s to adjust layouts for a bowlers positive axis point, rev rate, axis rotation and tilt.  Elimination of extra holes in these balls will not significantly affect ball reaction.
  6. No-thumbers (most two handers) are turning up in greater numbers and getting better. No-thumbers can hold the ball with their hand cocked to one side or the other, and/or put fingers in deeper and get totally different reactions on the same ball…on purpose!  Try doing that if your thumb is in the ball!

Rob Bailey, Rob Bailey’s Pro-Shop, LLC

Sun Prairie, WI  53590


6909 Briar Lane
Sun Prairie, WI 53590


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