For many, choosing a bowling ball is as simple as walking into the alley, renting some shoes and picking a ball off the rack. You can do that as often as you want, and there's nothing wrong with it. However, any improvement you seek to make in the game is going to be tempered by the lack of performance you'll get out of the ball.
When you buy your first bowling ball, it will come without holes in it (it is possible to buy balls with holes already drilled, but that's almost the same as choosing one off the rack for free at the bowling alley). So, how do you know the best way to get your ball drilled?
Find a Pro
Pro-shop owners and professional drillers will be extremely important in drilling your ball, and will be able to help immensely with the steps outlined below. It's a good idea to review this article, then ask any questions of the person who will be drilling your ball, as he or she can work directly with you to give you the best layout for your game.
The size of the holes and the distance between them is the thing with which you need to be concerned the least. Your ball driller will measure your hand and fingers and easily be able to determine the proper layout of the holes. The real question is: where do the holes go? The ball is spherical, but that does not mean the holes can go anywhere and give you the same effect. The location of the holes will dramatically impact how your ball behaves on the lanes.
Locate the Pin and Center of Gravity (CG)
The pin is marked as a solid, colored dot on the ball. This represents the top of the core inside your ball. When the balls are being made, the core has to be perfectly centered inside, so manufacturers use a pin to suspend the core. Once the mold hardens, the pin is removed, leaving a small hole that must be filled. That's the colored dot you see. The location of the holes to be drilled, in relation to the pin, is what makes the ball behave in different ways.
The center of gravity, not surprisingly, marks the center of gravity of the ball. This is a smaller mark, either a small punch or a circle, located a couple inches from the pin. The center of gravity won't affect much how your ball rolls unless you are a highly advanced bowler, but will help your ball driller based on its relation to the pin.
Locate Your Track
The track is the ring or rings of oil left behind on your ball after a shot, representing the parts of the ball that contact the lane during a shot. You can use a previously used ball as a reference, or your pro-shop operator can have you throw a couple shots with a similar ball to find your track.
If you have multiple rings on the ball, measure the PAP using the ring closest to the thumb hole and farthest from the fingers.
Locate the Positive Axis Point (PAP)
The positive axis point (PAP) of a bowling ball is different for every bowler. Your pro-shop operator will be able to help you find the PAP, which is the spot on the ball equidistant from every point of the ball's track. Think of it this way: there is one point on the ball that is the same distance from every piece of the oil ring around the ball. That is your PAP.
To find the PAP, the best thing to do is rely on your pro shop's equipment. There are tools that can find your PAP immediately, and other methods to use if your pro shop doesn't have those tools.
Why Does it Matter?
Every bowler is different. Even if you and a friend have hands exactly the same size and each purchase the exact same model of bowling ball, you should have different drilling layouts due to your individual PAPs (there is a small chance everything would work out that you have the same PAP, but that's unlikely). The point is, the relation of the pin to the PAP is different for everyone, and if you want to get the maximum performance from your ball, you should get it drilled for you and not based on anyone else.
When you can approach a ball driller and you know about your PAP and the type of action you want on your ball, it will make things a lot easier on that driller to do a great job for you.
Remember, since this article is a general overview, always ask any questions of your ball driller to clear up any uncertainties you may have. Bowling balls look simple on the outside, but are far more complex than spheres with three holes. The more you can tell your ball driller, the better results you'll get.