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What Is an Illegal Bowling Ball?

what is an illegal bowling ball

In a news release, the USBC said that balance holes are being used to change the design intent of the balls which is giving an unfair advantage to some players. This makes bowling balls with weight holes illegal to use as it gives a superior advantage over to pros that didn’t use the thumb holes.

To make up for this change, the USBC now allows bowling balls to “have up to three ounces of static side, thumb, and finger weight” for balls weighing more than ten pounds.  

This is an increase of one ounce. The USBC now also allows for a top weight of three ounces which eliminates the need to correct static imbalance with a balance hole.

Why Did the USBC Ban Weight Holes

Weight holes in bowling balls were a common sight on the professional circuit as late as 2020. Many pros, especially those hook bowlers who needed more action in their ball and delivered without using the thumb hole, had weight holes drilled into their balls.

The addition of a weight hole also provided a superior advantage to the pro over other professionals who inserted their thumbs deep into the ball and used their thumb to produce the same curving hook without weight holes. If you have watched a hook bowler and heard a loud popping noise as the ball is delivered, that is the bowler’s thumb leaving the thumb hole.

The USBC or United States Bowling Congress soon realized that not only did the extra weight holes allow an uncompetitive disparity, but bowling with weight holes allowed a bowler to alter the design intent of most bowling balls completely. It meant the bowler was using the ball to achieve results the ball was never designed to achieve.

What Is a Balance Hole in a Bowling Ball For?

The purpose and efficacy of a balance hole will probably change depending on who you ask. Generally, balance holes are used as tools to manipulate ball motion. Bowlers who have a solid understanding about balance holes on the ball’s motion tend to make better layout decisions, have better ball motion, and improve their overall bowling game.

Just remember, a well-placed balance hole won’t help you improve your bowling score if your execution is lacking.

Weight Holes

Weight holes were the original term for balance holes. When first created, weight holes were almost exclusively used to get a ball back within the legal limits of static imbalance. If a ball had too much side weight, a hole can be drilled to decrease its weight.  

At some point, the ball drillers realized that the holes they were creating could be used to manipulate the ball motion. Specifically, the balance hole was affecting the ball’s RGs (Radius of Gyration) and differentials.

Gradient Balance Line Hole System

Invented by Mo Pinel of MoRich Enterprises, this is the most popular balance hole system in use today. The Gradient Balance Line Hole system defined four standard balance hole placements, P1, P2, P3, and P4.

This new system gave bowlers a shared understanding and vocabulary for balance holes and if nothing else is a jumping-off point for understanding the basics of balance holes. It also standardized the hole placement, which is helpful for less-skilled ball drillers.

Here is how each balance hole in the Gradient Balance Line Hole system works:

  • P1: Reduces the bowling balls dynamics by almost twenty percent. This will weaken the ball’s motion by reducing the flare.
  • P2: No discernible difference in how the ball rolls. This placement is strictly for keeping the ball within USBC weight regulations.
  • P3: Increases the ball dynamics by twenty percent. Strengthened ball motion with increased flare.
  • P4: Increases the ball dynamics by forty percent. Significant ball motion increase and track flare.

The USBC Levels the Playing Field

To level the playing field, the USBC changed the rule not once but twice. In May 2014, the USBC ruled that bowlers could have only one weight hole drilled in their bowling ball if they delivered the ball without using the thumb hole.

In August of 2020, the USBC adopted another ruling which banned weight holes altogether. The legislation went on to say that “no thumb hole” bowlers who had weight holes drilled into their balls were, in essence, bowling with two weight holes in their bowling ball, and this constituted an unfair advantage.  

This new ruling stated that a bowling ball could have no more than five holes, and a bowler must demonstrate that each hole can be used when gripping the ball. The rule stated that the bowler didn’t need to use all of the gripping holes when delivering the ball but had to demonstrate the bowler could place a finger in each if required.

The ruling caused several pros who didn’t use the thumb hole during delivery to fill the thumb holes in their bowling balls. However, the USBC also made significant equipment changes which added three ounces of static weight on either the side, top, or bottom of the bowling ball to lessen the impact of the ruling.

How Do I Fix The Balance Hole On My Bowling Ball?

Take your bowling ball to your local pro shop and request that they make your ball legal. Don’t be surprised if you have to leave your ball overnight. Expect to pay between $40 to $60 to have a pro shop take care of this for you.

Some bowlers like to save themselves money by plugging their own balance holes. However, we don’t recommend you doing it yourself as your ball may not be legal to roll in leagues if not correctly done. And the price of buying a brand new ball starts around $150, a whole lot more than just paying for the hole plug!

When Can I Use My Bowling Ball With Balance Holes?

The only place balance holes are no longer legal are in USBC-sanctioned competitions. That means in regular play and local leagues, your balance hole ball is still legal. Of course, you should check with your individual league just to be sure. 

But if you don’t want to plug up your favorite ball, you don’t have to; you just can’t use it in USBC competitions.

Will Plugging My Bowling Ball Affect Its Performance?

As long as the cover stock (the outer shell) of your bowling ball is maintained correctly, plugging your ball will not affect its performance—another excellent reason to have your local pro shop do this for you. If you purchased a used ball with a plugged balance hole, you might want to take it in to see if it is appropriately weighted.

Basic USBC Physical Specifications For Bowling Balls

Spec Minimum Maximum 

Diameter 8.500” 8.595”

Roundness None 0.010” total run out

Hardness(average)**** 73D

Top Weight (10.00 pounds and greater) *** None 5 oz

*** Top weight spec is a manufacturing spec for undrilled balls effective January 1, 2020 

**** Minimum hardness changed to 73D on December 31, 2020. Production of models previously approved below 73D must cease after July 31, 2022.

What Bowling Balls are Banned by the USBC?

Click Image for More Info

Regardless of the number of holes drilled in the bowling ball, there are a few bowling balls the USBC will not allow a professional bowler to use. In March 2017, the USBC banned using two of the Motiv Corporation’s bowling balls – the Jackal and the Jackal Carnage.

The reason for banning both bowling balls is mathematically complex. Simply put, the certification revocation happened because both the Jackal and the Jackal Carnage exceeded the maximum gyration and differential radius. Both bowling balls were banned from use, and the company was fined and sanctioned for over a year.

Motiv announced the discontinued manufacture of both bowling balls, but the ban resulted in a net loss of over a million dollars. Even worse was any professional who placed in or won a tournament knowing they were using banned equipment was subject to forfeiture of their winnings.

Other Bowling Balls that Are Banned by USBC

  • Active Bowling Clear Ball (White)  
  • ABS Lane Navi  
  • ABS Accu Line Custom (All Colors)
  • ABS Galaxy Jupiter (Clear Pin)  
  • ABS Viva SA
  • ABS Gyration II LRG (Purple/Black/Gold)  
  • ABS Galaxy Mercury (Clear Pin)
  • AMF Velocity Blue  
  • AMF Michael Jordan
  • AMF Velocity Green  
  • Columbia Throttle Tuning  
  • Columbia Bonanza 2 (all Colors)
  • Columbia Reaction Arc Platinum  
  • Columbia Power Rock
  • Columbia Reaction Express
  • Brunswick Hockey Puck Ball
  • Elite Alien Tour   
  • Ebonite Quasar  
  • Ebonite Electric Zoom
  • Genesis Newklear Exceed  
  • Hammer Amazing Scandal (Red Pin)
  • Hell-Bent Dynamo  
  • Hell-Bent Brawny
  • Hell-Bent Dynamo Red/Black
  • Lane Hawk Whiskey Bottles
  • Lane Hawk Lady in Glass 
  • Lane Masters – The New Standard Limited Edition
  • Lane Masters Gold Diamond (White Pin)
  • Lane Masters – Figjam Clearance
  • Lane Masters Black Pearl Poseidon
  • Lane Masters Tank-44 Signature
  • Lane Masters TM Signature
  • Lane Masters Terminator Redemption 
  • Legends Hellfire  
  • Lord Field Blue Diamond Sparkle  
  • Lord Field Higgs Force Red/Blue
  • Lord Field Exodus Iron 
  • Lord Field Pin Hacker  
  • Lord Field Korrupt Attack  
  • Lord Field Terminator Cyborg
  • Lord Field Heritage
  • Lord Field Zaru Black M-TECH RCF  
  • Magic Bowling Service Twin Turbo  
  • Motiv Jackal Carnage  
  • Motiv Jackal  
  • QMR Fly Bullet L Pearl  
  • Visionary AMB Centaur Orange/Blue  
  • Twins Sports Summit α (Alpha)  
  • Via Rolling X  
  • Via Cylinder  
  • Via Horsepower  
  • Via Trump Star  
  • Via Planet X

Did you know some bowling balls actually have scents? Storm bowling balls like this one have special fragrances added into the ingredients during the manufacturing process. Fragrances like birthday cake and grapevine are just some of the scents that they have to offer. It’s said that fragrances help bowlers maintain their focus while throwing.

Changing Static Weights in Bowling Balls Forced Changes

Although the new static weight ruling on bowling balls by the USBC did compensate for the ban on weight holes, the banning and the order forced many professional equipment changes.

Pros were forced to either have their bowling ball weight holes filled and spend many hours practicing to compensate. Many purchased new bowling balls and started the almost daunting task of changing their stance and delivery at the line. Some were forced to learn a different way of holding their bowling balls.

The rule change did cause a lot of anxiety for a bit, but just as many professional bowlers made the changes, bought the equipment, and practiced as they always did. These pro bowlers learned to win with the new equipment. 

Final Thoughts

After a rather lengthy study about balance holes, the USBC determined that balance holes were being used to change the design intent of the ball, creating an unfair advantage for the bowlers using them. You will find a wide range of opinions on this matter amongst bowling enthusiasts.  

Whether you are a fan of the balance hole or not, you can no longer use a bowling ball with a balance hole in USBC competitions. You can have them plugged for a fairly reasonable price and continue to use your favorite bowling ball just like always.

Unless they play in USBC competitions, most bowlers will not be affected by this rule change.

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