Bowling Ball Drilling Options

The holes in a bowling ball affect a bowler's roll. Holes placed too closely together, spaced too far apart or that don't offer enough width for the bowler's fingers can offset the roll, costing a high score. Some professional bowlers will drill their own holes on a blank bowling ball so that they can customize the holes. When considering this alternative, it's best to familiarize yourself with bowling ball drilling options.

  1. Sizing

    • Sizing is a main concern for bowlers. Bowlers don't want the holes to be so large that the grip is lost and the ball slips away, or so tight that the bowler's fingers get stuck in the holes. It is appropriate to measure the bowler's fingers, using a ring sizer. Once the fingers are sized, the holes can be drilled according to that circumference so they are comfortable and effective.

    Alignment

    • The holes' alignment plays into the effectiveness of the bowler's grip. Alignment not only relates to where the two finger holes and one thumb hole are spaced in relation to one another, but it also has to do with where the holes are in relation to the center line of the ball, as well as the holes' angle. Holes are not drilled straight through, but are angled, or pitched, for a specific bowling effect. For instance, a back pitch for the thumb hole lets the thumb release from the hole with more ease, while the fingers -- with forward-pitched holes -- hold up most of the weight.

    Center of Gravity

    • Each bowling ball has a specific center of gravity. When you purchase a bowling ball or use somebody else's, you notice that the center of gravity is marked on the ball somehow. As you drill into the bowling ball, you must consider where the holes are being drilled in relation to the center of gravity. Drilling the holes on the center line of the center of gravity will have a straighter roll effect, while drilling the holes off to the side may cause the center of gravity to pull in a different direction, which might be beneficial for bowlers who roll curves.

    Top Weight

    • It is important to understand top weight so that you know whether you are drilling holes into the top or bottom of the ball. Bowling balls have what's known as top weight: extra ounces of weight built into the top of the ball to account for the loss of weight caused by drilling holes. You should not drill holes into the bottom of the ball, because the excess weight on the top will skew the ball's roll. For that reason, know which side is the top when you start to drill.