"do the dies have to be the same brand as the press or are they one size fits all"
All modern dies with a few exceptions use the same threads and fit all brands of modern presses. Different brands can be "mixed and matched" at the same time.
Lyman dies for the 310 tool, the Dillon SDB dies, .50 BMG dies and a few others use different size/threads on their dies.
Some older Lee dies do not have enough threads on the outside of the dies for the lock ring to work. This can usually be overcome by installing the lock rings on the bottom.
Last edited by TimW77; September 14, 2012 at 12:19 PM.