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must be included. Symmetric Bowling Balls Examining bowling ball
symmetric core designs also involves a quick comparison to
asymmetric core bowling balls and also involves scientific
descriptions and terms of elements involved in bowling ball
construction. Let's examine some of these terms such as bowling
ball symmetry and try to clarify how these terms relate to
bowling ball motion: 1. Symmetrical Core (undrilled) - A ball
where the RG (radius of gyration) values of the Y (high RG) and
Z (intermediate RG) axes of the ball do not differ by more than
5% of the total differential of the ball. 2. Asymmetrical Core
(undrilled) - A ball where the RG (radius of gyration) values of
the Y (high RG) and Z (intermediate RG) axes of the ball differ
by more than 5% of the total differential of the ball. As a
quick sidebar, it has been proven through United States Bowling
Association (USBC) field