Bowling Ball Specifications
Learning bowling ball specifications
can help you better understand bowling ball construction and ultimately help you choose your next bowling ball. Reviewing some of the useful details relating to the manufacturing limits and tolerances under the guidelines of the United States Bowling Congress
(USBC) will help you become familiarized with bowling ball specifications
Any bowling ball used in USBC certified competition must be approved and identifiable as a ball listed in the approved bowling ball list at USBC headquarters. A bowling ball must be constructed of solid material without liquids or voids in the center. Any materials added to or included in the coverstock shall be equally distributed throughout the entire coverstock of the ball. Altering a ball in any way so as to increase its weight or cause it to be off balance outside specifications is prohibited.
The surface of a ball shall be free of depressions or grooves other than holes used for gripping purposes. No foreign material may be placed on the outer surface of the ball. If the surface friction is altered by sanding or polishing, the entire surface must be prepared in the same manner. Plugs, grips, or tape may not extend from the inside of a gripping hole beyond the surface of the ball.
20 other noteworthy specifications:
- The weight of a ball shall not exceed 16 pounds. There is no minimum weight.
- The surface hardness of bowling balls shall not be less than 72 Durometer D at room temperature (68 - 78 degrees F).
- No chemicals or solvents may be used to alter the surface hardness after a ball is manufactured.
- The circumference of a bowling ball 13 lbs. or greater is 26.7" minimum, 27.002" maximum.
- The diameter of a bowling ball 13 lbs. or greater is a minimum of 8.5" and a maximum of 8.595".
- The Radius of Gyration of a 13 lb. ball or greater is a minimum of 2.46" and a maximum of 2.8".
- The Differential of RG for a 13 lb. ball or greater has no minimum with a maximum of .06".
- The Coefficient of Friction of a 13 lbs ball or greater has no minimum with a maximum of .32 rating.
- The Roundness of a 13 lb. ball or greater is .01" tolerance.
- 5 holes maximum are allowed for gripping purposes, all for the same hand.
- 1 hole for balance purposes is permitted not to exceed 1 1/4" diameter at any point through the depth of the hole.
- 1 vent hole is permitted not to exceed 1/4" diameter.
- No more than 3 ounces difference in 10 lb. balls or greater between the top half of the ball and the bottom half of the ball is permitted.
- No more than 1 oz. difference in 10 lb. balls or greater between the right and left sides of the ball and between the front and back of the fingers holes is permitted.
- Any 10 lb. ball or greater drilled without a thumb hole may have no more than 3 oz. difference between the top half and bottom half of the ball.
- 2 oz. of difference between the top and bottom halves of a ball and 3/4 oz. or less difference from the left to right and front to back of finger holes is permitted in balls weighing between 8 and 10 lbs.
- The center of the grip of a ball is determined by measuring the cut or front edge of each finger hole to the front edge of the thumb hole.
- Plugs may be inserted into a ball for the purpose of re-drilling the ball.
- Slugs may be used in place of plugging finger holes only when a new hole is drilled completely through the slug.
- There are no color restrictions for a bowling ball so long as all additives in the coverstock are distributed throughout the entire coverstock of the ball.
Since there are no tolerances provided for coverstock
texture, the manufacturers of bowling balls offer a variety of textured coverstocks to match with varying oil lane conditions. Therefore, as a bowler, your first decision in choosing a new ball should be the type of coverstock needed to best match with oil conditions where you intend to use the new ball.
Generally, solid coverstocks are typically pliable and will grip the lane better than a stiff or pearl coverstock. A very aggressive, solid coverstock is designed for heavy oil whereas a a moderately aggressive, solid coverstock will work on medium oil conditions. Of course, your skills as a bowler come into play regarding variables such as rev-rate, ball speed, and bowling ball axis tilt. For dry lanes, using a stiff or pearl coverstock increases ball skid on the front part of the lane and helps conserve energy for the back end of the lane.
Altering the surface texture is certainly permitted so long as the entire surface of the ball is textured the same way. You can wake up the coverstock of a ball by using the services of a pro shop and the high speed ball spinner to apply any grit of pad to the surface of the ball so the texture best matches the oil conditions you are challenged to overcome. The same is true with cleaners and polishes. Use of these substances are permitted so long as the entire surface of the ball is prepared in the same way. You can use USBC approved cleaners during competition and you can clean and polish your ball by hand after competition to prepare the coverstock of your ball prior to using it next time you bowl.
Selecting the drilling layout is the other factor which will influence bowling ball motion while the ball travels down the lane. There are an extremely high number of scientific layout patterns to choose from that the decision process can be confusing. We recommend you access of "Drilling Layouts
" feature on our home page before doing anything else. Reference the given manufacturer and given bowling ball you have chosen or are considering choosing as your next ball and click on the options provided to access the layout suggestions provided by the manufacturer. You may also review the information about the rev-rate, about the overall shape of motion a given layout will accomplish, and information about oil conditions a given layout matches.
Next, consult with your ball driller and make a joint decision how best to layout the ball for drilling and matching the lane conditions you are targeting. If there is one key factor to consider above all others, then it would be to try and match the break point of the bowling ball to the break point on the lane. The bowling ball break point is controlled by length potential and hook potential ratings of a given ball, by the surface texture preparation, by the layout pattern selected in drilling the ball, and by the individual bowler's abilities. Since the break point of the lane is determined chiefly by the distance and cross lane ratios of oil application by the lane machines settings and by the volume of oil used in the given ratios, the break point down the lane can range from 5-7 feet past the final distance oil is applied to the surface. As a rule of thumb, the break point on the lane is nearer the edge of the lane on shorter distance oil patterns and closer to the center of the lane on longer distance patterns.
always recommends that you consult a certified coach when seeking greater information about the break point of the lane. It is also recommended to consult with your ball driller when trying to determine a layout pattern and surface preparation strategy to also match the break point of the ball to the lane. Of course, it never hurts to sharpen your bowling skills by working with a certified coach or instructor so your ability to make consistent deliveries improves with practice.
We hope this information about bowling balls provides useful insight into achieving success on the lanes. While you are visiting our site today, please check out the vast menu of bowling consumer products we offer at great prices, with no shipping charges, and delivery right to your doorstep! bowlingball.com
has become the No. 1 “e-tailer” of choice for bowling equipment by the consumers of America. Ordering is an easy process by following simple online instructions. Thanks for visiting bowlingball.com