New to loading 300 whisper

[svenska]

I have some 223/556 brass I would like to make into 300 whisper/fireball. I bought a two die set from Redding in 300/221 Fireball. Would the three die set from Redding be better or another manufacturer?

I have always loaded pistol ammo. I have never done rifle ammo. How do I set up the dies to size and seat the bullet properly? I will be using a single stage press.

Like I said above I am new to this type of shooting.