If you buy a 3 die set from say, RCBS, you will get a sizing die, an expander die and a seater/crimp die. Bullet seating and crimping done in the same die; not a good process in my view.
If you buy a 3 die set from Dillon, you will get a sizing die, a seating die and a taper crimp die. Notice that there is no expander die! Case mouth expansion on a Dillon press is done with an expander on the powder measure.
The Dillon dies are nice in that the internals can be removed for cleaning withouth changing the settings. With lubed bullets, cleaning the seating die will be required - frequently.
The problem is, neither set is complete (IMO). I would prefer to taper crimp as a separate operation from bullet seating. So, with the RCBS set, order a separate taper crimp die. For the Dillon set, order an expander die from somebody else.
You didn't say which press you were planning to use. I can tell you, for certain, you don't want to reload pistol ammo on a single stage press. It just takes too long. Sure, most everybody starts out that way but after loading a few hundred rounds they are looking for something else.
There are a few 'stickies' at the top of this forum that discuss loading equipment.
"No matter how cynical you become, it's never enough to keep up." - Lily Tomlin
Last edited by F106 Fan; 11-24-2011 at 09:28..