Plastic baseball bat and method of making the same

A baseball bat having a central core of expanded thermoplastic resulting from a mixture of thermoplastic and a foaming agent surrounded by a discrete skin of thermoplastic per se, and having been made by a process wherein both the core mixture and the thermoplastic per se are coinjected while in conforming contact and while the thermoplastics are in a heated and viscous state and coinjected under pressure in a mold cavity having the shape of a baseball bat, the outer surface of the thermoplastic per se being in contact with the mold cavity and the outer surface of the mixture being in contact with the inner surface of the thermoplastic per se, the thermoplastic per se and mixture being distinct materials which are united at the surfaces which are pressured into contact while the thermoplastics are in the viscous state and which become joined into a unitary rigid body upon cooling.