Container and overflow chute agitation (vibration) is applied through the base of the containers while located within the central turret. Containers are held within a star-wheel centre turret and driven over a fixed, twin radial track arrangement. An independent radial track is positioned between the fixed tracks and is oscillated by an eccentric drive arrangement. This provides a harmonically controlled lifting of the container and in-turn, the overflow chute located above. On the down stroke the centre rail passes below the fixed rails, effecting a sharp tamping action. The frequency of vibration may be adjusted to suit individual product requirements, providing the optimum settling for product being filled.