A method for dispensing a flowable material is disclosed. The method comprises holding a hydraulic fluid in a reservoir at a negative pressure, inserting a cartridge tube, having an interior, into a cartridge housing, locking an over-center mechanism relative to the cartridge housing so that a hermetic seal is created between a plunger and an interior of the cartridge tube and between an end-cap and the interior of the cartridge tube, and turning a rotary actuator in a rotational direction so that a linear actuator advances a piston within the reservoir to transfer at least a portion of the hydraulic fluid from the reservoir to a flowable-material dispenser through the end-cap and into the interior of the cartridge tube, causing the plunger to advance within the cartridge tube in a forward plunger direction, away from the end-cap.