Here are some of the different types of bowling ball cover-stocks and cores to date. First there are 5 types of cover-stocks that I am going to talk about; they are plastic, reactive pearl, reactive solid, reactive hybrid, and particle. There are 3 main types of cores in a bowling ball which include 3-piece, 2-piece symmetrical, and asymmetrical. They are outlined in more detail below.
1. Plastic - Usually used in 3-piece cores. It does not have much traction on the lane and is lower in price. It is mainly used as a spare or a beginner ball.
2. Reactive Pearl - Used in all types or cores. It has a more of a skid snap reaction normally.
3. Reactive Solid - Used in all types of cores. It normally has an earlier and smoother reaction than the pearl.
4. Hybrid Reactive - Mainly used in 2-piece symmetrical and asymmetrical cores. This type of cover is made to give the bowler the best of both worlds. It has a combination solid reactive and pearl reactive. Mainly used on over and under bowling lane conditions.
5. Particles - This was a cover-stock that was made to combat heavy oil. It had pieces or particles in the reactive cover to help it grab the lane surface. There are not many companies making particles any more, but there are a few. It was mainly used in 2-piece symmetrical and asymmetrical cores.
Note: Urethane Cover Stocks that were popular in the 1980's are now making a come back. They are not as aggressive as reactive bowling balls and are more powerful than plastic. In addition, they are usually smoother in transitioning but do not have the hitting power of the reactive balls.
1. 3-piece cores - Used mainly in plastic balls. It is made of 3 pieces containing an inner core, a pancake type weight block at the top, and the cover-stock.
2. 2-piece symmetrical cores - Used mainly in higher performance bowling balls. They will tend to have a smoother and more stable roll. It is symmetrical so this means it is even on all sides. It contains an inner core and outer core covert-stock.
3. Asymmetrical cores - Used mainly in high performance bowling balls. It is not even on all sides because it is asymmetrical. This type of core is used to fine tune a bowling balls reaction to the bowler�s style. This is an advanced technique in bowling where the pro-shop operator matches the bowling ball drilling to the bowler�s style. Speed and revolution rate as an example.