Abstract: Extrusion apparatus for production of a shaped article comprising one or more filling materials enclosed in a coating material. Included in the apparatus are inner and outer conduits through which the materials are extruded toward an iris valve adjacent the terminal portion of the outer conduit. An inner conduit preferably terminates within the outer conduit at a distance from the iris valve equal to the distance between outer surface of the inner conduit and inner surface of the outer conduit. Operation of the iris valve both determines the length of the article and the shape of forward and rearward ends of the article.