Even if you havent seen the 1996 cult comedy Kingpin about bowling and redemption, you can probably imagine Bill Murrays indelible character Ernie (Big Ern) McCracken: With sweat on his brow and a comb-over flapping comically in the breeze, Murray stands at the top of the lane, gripping his beloved ball. He whips the crowd into a frenzy as he holds it alofta transparent ball with a single red rose encapsulated in the centerthen hooks it down the lane, scoring a crucial strike in the tournament final.

Although many pro bowlers cherish Murrays over-the-top performance, they might have a few bones to pick about the technical aspects of this scene. It would have to be extreme conditions on the lane for a ball like that to come into play, says professional bowler Kelly Kulick. Typically, pro bowlers use this type of smooth-surfaced ball when they just want to pick off one or two pins remaining at the end of the lane to score a spare. To knock all 10 pins down and secure a strike as Murray did, savvy bowlers typically use something else entirely: balls that have an asymmetric weight block in the center and that are coated with a porous polyurethane shell.

Ancient Egyptians, who invented a crude form of the game, would certainly be impressed by todays bowling balls, which are a big improvement over their stone predecessors. In fact, the sophisticated materials science slipped into modern balls has helped improve player performance, says Danny Speranza, senior director of equipment specifications and certifications at the U.S. Bowling Congress, the sports national governing organization. Between 1910 and 1980, only one out of about 3,000 bowlers registered with USBC could score a perfect gamethats getting a strike 12 times in a row. By 2007, that figure had increased to one out of about 30.

Costing anywhere from around $50 to $250 depending on its design, a modern bowling ball typically contains three parts: an inner core, an outer filler core, and a shell, which is called the coverstock in bowling lingo.

The exact materials that go into making each part of the ball are considered proprietary technologies that are closely guarded, says Victor Marion, director of R&D for Utah-based manufacturer Storm Products. In general, though, the inner core is made of powdered metal oxides such as calcium or iron oxide mixed with a resin and catalyst to harden the mixture. This is the heaviest part of the ball, and its shapewhether symmetric like a sphere or asymmetric like a lightbulbinfluences how the ball rotates down the lane.

The outer core is light, yet rigid, containing substances such as polyester or glass beads, also mixed with a resin. Manufacturers use this part of the bowling ball to fine-tune its final weight. Heavy 7-kg bowling balls are quite dense, but balls weighing 4.5 kg or less have such a low density that they can float in water.

And dont let the outer layer of the ball fool you with its bright, swirled colorsand sometimes delightful smell (Storm Products impregnates its coverstock with fragrances such as birthday cake). The outer shell of the ball is not ornamental; it seriously influences the balls motion as it hurtles down the lane, Speranza says.

The shell is all about generating friction with the lane, Storms Marion explains. Thats where a lot of the magic happens.

When a bowler releases a ball, it skids down the lane through a thin layer of mineral oil. About two-thirds of the way down an 18-meter lane, the ball enters a nonlubricated zone. There, it gains traction like tire treads on a road. At this point, depending on what type of spin the bowler applied to the ball during its release, the ball can really begin to curve, or hook, across the lane to make the pins scatter.

Lane conditionsthe amount and pattern of the oil applied to the lanecan vary widely from bowling alley to bowling alley. And the conditions can change over the course of a game or tournament as balls soak up or spread around the oil on the lane. Recalling the tire tread analogy, Marion explains that some days youre driving in California and its a sunny day, and some days youve got six feet of snow and you need every bit of traction you can get. On those so-called sunny days, when lane conditions are fair, bowlers dont need a ball that creates a lot of friction with the lane, but on the snowy days, they might want something with a more porous, and therefore rougher, outer shella ball with some studded snow tires, so to speak. Good bowlers know which ball matches up best for a particular game, Speranza says. If theyre going to a tournament, pros can take six to eight different balls with them.

Kulick says that for professionals who bowl full-time, that number can even go higher. Shes been known to ship 10 balls and carry five others with her when traveling to tournaments.

Usually, bowlers will start out with the most aggressive ball in their bagthe one with the highest friction, Kulick adds. Then theyll keep adjusting which ball they use depending on where the ball starts to hook as it rolls down the lane.

The most basic of outer shells on a bowling ball is made of polyester. This type of plastic covering is rigid and has low friction, and you use it when you want to throw straight, like when you need to topple just one or two pins to pick up a spare, Speranza says. Balls with a polyurethane shell, on the other hand, experience higher friction with the lane. To make these rough yet pliant shells, which are useful for knocking down many pins at once, manufacturers mix isocyanates and polyols. If they want to make an even higher friction ball with a so-called reactive resin shell, they add proprietary ingredients such as plasticizers to a urethane base layer to create a multitude of cross-links in the polymer strands, giving the balls coating more porosity and roughness.

These high-friction reactive resin balls were favorites among pro bowlers for nailing strikesat least until recently. According to Speranza, one of the biggest changes in the sport in the past 10 years is that some pro bowlers now throw the ball with a two-handed release rather than a one-handed release. One celebrity bowler, Jason (Belmo) Belmonte had great success with the technique in tournaments and popularized it.

When you throw a ball with two hands, you can put more spin on it and therefore get more hook, Speranza explains. Two-handed bowlers have discovered that they dont often need super high-friction balls. They dont want to over-hook the ball on the lane and send it into the gutter, so theyre increasingly taking a step backward to balls with a less sophisticated urethane shell.

If all this strategizing among pro bowlers sounds complicated, for ball manufacturers, its even more so. Theyre subject to the rules and regulations of USBC. To level the playing field and make sure that none of the nearly 46 million bowling participants in the U.S. has an unfair advantage because of overly engineered equipment, the organization sets limitations on parameters such as the coefficient of friction and surface roughness of a bowling balls outer layer.

Its amazing how complicated it is to get the right level of performance in a ball and still be within specifications, says Marion, who formulates new ball designs for Storm each year. To get the chemistry just right, he adds, its like putting together a jigsaw puzzle.

Whats even more complicated? Bowling a tournament-winning strike with an ostentatious rose-decorated ball not really designed for the task. Big Ern was even more of a phenom than the crowd suspected.

UPDATE: This article was modified on February 21, 2017 to refresh its information and data.

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What's in a bowling ball, and how does its chemistry help topple pins? - Chemical & Engineering News (subscription)