Star did not make dies for this caliber. The only way to load 357 Sig on a Star would be to use a tool head for 7/8" Dies. Use 7/8" Dies for Sizing, Bullet Seating and Taper Crimp. Use a Star expander for 9MM. Use a Shell Plate for 40 S&W. You would probably need to make a few other modifications as well.
Bruce Williams