A process is presented for the production of ammonium sulfate nitrate. The process provides for producing a highly uniform product and having a substantially uniform size. The process includes reacting ammonium sulfate and ammonium nitrate to form an FASN slurry melt. The slurry melt is continuously stirred and heated to keep the slurry melt under a shear thinned condition and at a uniform temperature until the slurry melt is extruded, cooled and solidified.