A method of manufacturing a catalyst, a catalyst precursor, or a catalyst support comprising: (a) mixing a refractory metal oxide or precursor thereof with a liquid to form a paste; (b) adding said paste to an extruder, the extruder having a die plate comprising one or more dies, each die having a plurality of apertures, the outlet of each aperture having a cross sectional area of 6 mm.sup.2 or less; (c) extruding the paste through the apertures to form catalyst support extrudates; wherein the inlet of the apertures has a greater cross sectional area than the outlet of said apertures; and wherein for at least one die the combined cross sectional area of all apertures at the inlet relative to the total cross sectional area of the die at the inlet is higher than 50%.