The drilling of a bowling ball is just as intricate as the sport of bowling itself. When professionals drill a bowling ball, you have to take certain factors into consideration: What kind of grip does the bowler use? Is it conventional, fingertip or semi-fingertip? Does the ball belong to someone who is a casual bowler who goes to the bowling alley once in a while or does it belong to a league bowler? What is the makeup of the ball? The way the ball is drilled has a big effect on a bowler's release and the ball's reaction in addition to the individual's hand positioning and oil pattern on the lane.
- The bowler will have to get their fingers and hand span measured. Drillers have a bowling ball-like measuring tool to use for this purpose, which has many holes in many different sizes all around it. A person will place their fingers inside holes that seem appropriate for the size of their thumb, middle and ring fingers, and the driller will record the sizes to ensure proper drilling for the ball. Sometimes, a driller will make the holes in the bowling ball slightly smaller than the measurements, but this is fine, as they can always go back and enlarge the holes if necessary. More often, they will make the thumb hole slightly bigger due to the fact of the contraction and expansion of the finger during different seasons throughout the year. In the summer, the grip will be tighter, while during winter months, the bowler will find him or herself adding more tape to the thumbhole for a better grip.
- If the ball is being drilled using a fingertip grip, there should be a full span between the middle finger and ring finger holes and the one for the thumb. This is a more natural, relaxed grip for the more experienced bowler who owns a reactive resin ball.
- The alignment of the holes to the weight block inside the bowling ball is also important. If a bowler is right-handed and throws a hook, the ball would be drilled in such a way that the ball would hook to the left when thrown on the right side of the lane to hit the pocket between the headpin and the three-pin. Likewise, for a lefty or a right-handed backup ball, the drilling should be at an angle where the ball is going to hook to the right, from the left side of the lane.