Abstract: A bowling ball having an outer shell and a core comprised of a main body and a plurality of weight blocks. The outer shell is of uniform thickness, completely encases the core and has an outer spherical surface. The main body and the weight blocks combine to form a solid sphere. The weight blocks are of the same size, shape and material and have first curved surfaces which form a part of the outer surface of the core and second surfaces directed to the center of the sphere. The weight blocks are symmetrical about center axes thereof and have a greater density than the main body. The first and second surfaces of the weight blocks join at an edge. The weight blocks diminish in cross section, transverse to their center axes, from the edges to the lowermost portions. The weight blocks form a cluster around a vertical axis extending outward from the geometric center of the ball.

Abstract: A bowling ball which complies with the American Bowling Congress rules and which has the weight thereof distributed in such a manner that when the ball is rolled, the weight distribution produces a gyroscopic effect. The bowling ball has a segmented, light weight core. Two opposed segments are removed from an otherwise spherical core, and another segment positioned normal to the opposed segments is removed from the core. The third segment is replaced with a segment of relatively high density material to form a top weight which offsets the loss in weight occasioned by the subsequent drilling of finger holes. The core is centrally located within the ball and the main body of the ball is made of medium density material so that the main body material which fills the void provided by the two opposed segments provide two parallel arranged weights of medium density.