That's bad, Tex. Bullets are big enough. First thing to try is to take a sized case, flare the case mouth the least bit with anything tapered and handy, charge the case, and seat the bullet in the seating die. If that bullet is tight, your expander is too big. If it's loose, your sizer is too big. Either way, the die maker should make it right.
Brass may be a bit on the thin side, but the sizer should be tight enough to allow for that.
