Abstract: A blow tube for delivering particulate material from a container thereof to a mold to form a core has a unitary, elongate body formed of resiliently elastic material which enables the body to adjust and compensate for misalignment of the container and the mold. The blow tube body has a bore having a plurality of axially spaced sections so that when the particulate material is blown through the body by compressed gas, the density of the particulate material is increased and the velocity of the gas and particle stream is increased. The elasticity of the blow tube body enables the latter to expand in the event the particulate material clogs the blow tube, thereby enabling the clog to disaglomerate.