In the 3-Die set sizing and expanding (belling) are done in separate dies. The 3-Die set has a sizer die with decapping unit, expander die for expanding and belling the case mouth and a seater die with bullet seater plug(s) for seating and crimping the bullet.
Type : 3-Die Set
Caliber : 44-40 Winchester
Check out the entire range of products from RCBS.