A dispenser for viscous material packaged in a collapsible sleeve includes a chamber for receiving the packaged material and a piston rod and piston assembly for compressing the collapsible sleeve to dispense the viscous material through a dispensing orifice in a closure removably retained on the forward end of the chamber. The piston assembly includes a movement-limiting member having a distal surface that extends forward of a piston for limiting movement of the piston rod and piston by engaging the peripheral surface of the closure. The movement-limiting member also has an outer peripheral surface that is positioned inwardly of an inner surface of the chamber to provide an annular compartment for receiving portions of the collapsible sleeve therein when the viscous material in the sleeve has been dispensed.