What are Bowling Balls Made Of?

The first time I learned how to play ten-pin bowling games, I got intimidated by the balls’ overall look and weight. Since then, I’ve always asked, “What are bowling balls made of?”

After reading a lot of information on the net, I found that bowling balls are made of two major parts: the coverstock and the weight block. The coverstock is the outer layer of the bowling ball, and it has four different types. The weight block, on the other hand, has two types: high mass and low mass. To understand what these all are, read on to find out.

What is a Coverstock?

The coverstock of a bowling ball acts as its outer layer or shell. This is the part that we all see. There are a number of bowling balls with fancy designs that you can choose from.

As the outer layer, choosing the right coverstock is crucial because it makes contact with the lane’s surface. It determines how good your hook will be. Identifying the lane’s surface can help you choose the right coverstock for better gameplay results.

What are the Different Types of Coverstock?

There are four different coverstock types, namely Plastic (Polyester), Urethane, Reactive Resin, and Particle (Proactive). Each type gives out a different performance that can help turn your game around.

It is highly important to match the lane conditions to the bowling ball’s coverstock since it is one of the many factors that affect the game. Here are the different types:

Plastic (Polyester)

Out of all the types of coverstock, this one has the smoothest surface. Since it is smooth, it gives the least hook potential.

If you are a beginner bowler, bowling balls with plastic coverstock are ideal for you since they can fit properly in your hand. This is also the ideal material for straight bowlers because of its design.

Plastic bowling balls also act as spare balls. Most intermediate and advanced bowlers use this to shoot spares since it goes straight and can predict the ball’s movement.


If you have gotten a good grip with plastic bowling balls, you may want to start practicing using the urethane ones.

Bowling balls with urethane coverstock are more durable than plastic ones. They also provide more friction, therefore giving you higher hook potential.

Since it has a higher hook potential than plastic, urethane bowling balls are ideal for intermediate bowlers and for those who are starting to learn how to hook.

Even though it gives more friction than plastic, it is still controllable. In fact, most pro-bowlers who prefer to curve their ball’s movement use this as their spare ball.

This doesn’t mean that you have to abandon your plastic ball, though. Urethane and plastic bowling balls are good additions to your arsenal that might come in handy when you need it.

Reactive Resin

Suppose you want a bowling ball that gives a higher hook potential, friction, and pin action than urethane. In that case, the ones with reactive resin coverstock are for you.

However, these types of bowling balls have their own cons. When it comes to lane conditions, they are more sensitive and can cause many operator errors and they are also harder to control.

Due to its nature, only experienced pro-bowlers use this type of ball because it requires excellent lane conditions.

There are three main reactive coverstocks: pearl, hybrid, and solid. Pearl coverstocks are the strongest and the best for long games.

Meanwhile, hybrid coverstocks are versatile and can be used by all bowlers from beginners to advanced. Lastly, solid coverstocks are ideal to use in the early game and in the oiliest surface lanes. They will need the highest maintenance out of the three.

Particle (Proactive)

If you are playing in an oily surface lane, then bowling balls with particle coverstock are your best bet.

It has quite a bumpy surface which makes it ideal for breaking down the oil in surface lanes. It can provide the most friction as well.

Almost all intermediate and advanced bowlers have at least one particle bowling ball.

What is a Weight Block?

The weight block acts as the core of the bowling ball. It is found inside the ball, and it has two major categories: symmetrical and asymmetrical. Each one has its specific purpose and can be used according to how you want your gameplay to go.

The Two Major Categories of a Weight Block


Symmetrical weight blocks remain the same when rotated on the axis. It is ideal for later breakpoints, hooking conditions and helps the bowler achieve high rev rates at a slower speed.


Bowling balls with asymmetrical weight blocks are ideal for bowlers who have a hard time making shot revolutions.

This type of weight block has a better weight distribution in a spot than another, thus responding faster to friction, transition quicker, and create a ‘hockey-stick motion.’ The profile of the weight block changes when it is rotated on the axis.

How do I Choose the Ideal Bowling Ball?

If you are a budding bowler, it is better to start practicing with plastic bowling balls then gradually moving on with the other balls. Most follow this pattern: plastic, urethane, reactive resin, and particle.

Remember that you should not fully abandon the older ones when you upgrade to a different kind of ball to use. Know what ball is ideal to use according to the lane surface, length of the game, shooting spares, and your gaming style.

Ten-pin bowling is not only about strength and stamina, but it is also about how you intellectually maneuver the game.

Final Words

Now that you know what bowling balls are made of, you can make a better and informed decision in choosing the right ball for your gaming style. However, remember that the type of bowling ball is just one of the many factors that can give you great results. Each factor should work together to achieve a satisfying game performance.