What is a golf ball made of?

According to http://library.thinkquest.org/10556/english/high/history/hist05.htm

In 1901, the rubber-cored ball made its British debut. It was the invention of the fledgling American golf equipment industry. The idea belonged to Coburn Haskell, an employee of the Goodrich Tyre and Rubber Company in Ohio. Elastic thread was wound around a rubber core under extreme tension and then encased in a patterned outer cover of gutta percha. The Haskell ball initially had its skeptics until in 1902 where people were shown what a difference the ball made to the best players when Sandy Herd played four rounds at the Royal Liverpool course in 307 to beat the great Harry Vardon and James Braid by a shot. Herd used the Haskell ball for all 72 holes and he was the only man in the field to play with one.

From that moment, the Haskell ball has been improved to such an effect that it spawned a host of dicta from the R & A and USGA, the dual arbiters of the integrity of the sport. In 1920, they agreed the ball should weigh no more than 1.62 ounces and have a diameter of not less than 1.62 inches. From January 1931 however, the USGA turned its back on the collective agreement and introduced the "big ball", a ball having a minimum size of 1.68 inches and a maximum weight of 1.55 ounces. A year later, they raised the weight stipulation to 1.62 ounces. Subsequent attempts to settle for a uniform ball of 1.66 inches failed but finally, the USGA standard was also adopted elsewhere. The Professional Golfer's Association (PGA) in Great Britian was swayed by people who attributed the American dominance of golf to their usage of the big ball. It announced in 1968 that it was to experiment with the bigger ball of 1.68 inches in its tournaments. Soon it became mandatory. In 1974, the R & A made the big ball compulsory for the Open Championship. Under the rule revisions that came into effect in 1988, the R & A outlawed the small ball altogether.

In more recent times, the original gutta percha shell of the Haskell ball has given way to new and refined compounds. Balata replaced gutta percha in balls for the professionals and good amateurs while surlyn took over in balls for the novices. Millions have since been spent researching the properties of various formations of dimples. Many manufacturers have produced balls of new standards but most have been rejected for tournament usage. A few years ago, the USGA banned the Polara ball, claiming that it undermined the integrity of the game. The inventors of the ball engaged the USGA in expensive court proceedings but the prohibition was upheld. Ball manufacturing today is indeed big business. In January 1993, Spalding announced the launch of its Magna ball. It was a ball of 1.72 inches, larger than stipulated in the rules. The manufacturers claimed that the ball supplies golfers with more distance and accuracy while it spun less.

We used to slice the golf ball open, (about 2 centimeters), just enough to see the rubber bands. Then, take a razor blade, and start slicing the rubber bands one by one until you hear them start popping on their own. Then, you stand back, and as the bands break, they will eventually eject the hard rubber core like a cannon.
Sorry. You just reminded me of something we used to do a looonnnggg time ago! LoL!

P.S. - Seriously, you probably shouldn't try this at home. It could possibly hurt someone. The hard rubber core does come out with some force.

What is in a golf ball? Did they use to use rubber threads around the core of a golf ball?

A golf ball is made out of a rubber band ball encased in a gutta-percha shell. The dimples in the ball are made to increase speed and distance of a drive. It was invented in 1901 by Coburn Haskell.