Catalyst systems and methods for making and using the same are provided. The catalyst systems can include a plurality of silica particles and a metallocene catalyst and an activator supported on the plurality of silica particles. The polymerization catalysts have a particle size distribution in which about 10% of the particles have a size less than about 17 to about 23 micrometers, about 50% of the particles have a size less than about 40 to about 45 micrometers, and about 90% of the particles have a size less than about 72 to about 77 micrometers.