Abstract: A game ball for use as a conventionally sized baseball or softball comprises an inner core of a first material characterized by at least high durability; at least one locator pin of the first material extending radially outwardly from and affixed to the inner core; and a spherical outer core of a second material, characterized by at least high durability and conventional rebound. Preferably, the inner core has four integrally formed locator pins extending radially outwardly therefrom. These pins are positioned 90.degree. apart on an imaginary plane through the equator of the inner core. The first material is selected from the group consisting of cork, kapok, rubber, or a thermoplastic resin such as an ethylene vinyl acetate copolymer, an ethylene acrylic acid copolymer or a blend of both. The second material for the outer core, preferably polyurethane foam, consists of 100 parts of a resin mixture, a blowing agent, and either 51 or 60 parts isocyanate.

Abstract: A process for forming a rubber or vinyl coated baseball or softball is comprised of supporting a baseball or softball core within a mold cavity to position the exterior of the core uniformly equidistant from the mold cavity wall to provide a space between the core exterior and the cavity wall. A thermoplastic rubber or plasticized vinyl resin is injected into the mold cavity to flow into and fill the space between the core and the wall. The thermoplastic rubber or plasticized vinyl resin is allowed to solidify and a rubber or vinyl coated baseball or softball is removed from the mold.

Abstract: A game ball is comprised of a single spherical core and a cover. The core is comprised of a single spherical mass of partially blown copolymer of ethylene and at least one unsaturated monocarboxylic acid having from 3 to 8 carbon atoms. The copolymer contains up to 30 percent by weight of the acid copolymerized therein with foam at the center of the core and having a skin with the density substantially equal to the density of the copolymer. The game balls are baseballs and softballs.

Abstract: A method of forming a ball core is disclosed. A flowable homogeneous mass of a thermoplastic resin and a blowing agent is injected into the spherical cavity of a mold under temperature and pressure conditions sufficient to activate the blowing agent. The mold is cooled to 32.degree. to 65.degree. F. so as to form a skin on the surface of the mass. The mass is held within the mold cavity for a sufficient time so that the skin has adequate strength to prevent its rupture by blowing agent contained within the mass, upon removal of the mass from the mold cavity. The mass is cooled at an exterior temperature of 32.degree. to 65.degree. F. A ball core for baseballs and softballs is also disclosed.