Taper crimp dies were never meant to be used to apply a crimp which will prevent bullet movement because taper crimps are not suited for that. They are meant to remove case mouth flare required for proper bullet seating. Seat the bullet so the shoulder is just enough below the case mouth to allow you to apply a small amount of roll crimp. This is not an unusual practice as the 173 grain Lyman 358429 must be seated and crimped in this manner in order for the loaded round to fit in the cylinder of the N-Frame S&W M27 and M28 revolvers along with their pre-model number counterparts.

This bullet is designed for low velocity loads so there is little chance of the bullet jumping the crimp if there is the proper amount of neck tension to begin with. The heavy lifting in preventing bullet setback or crimp jumping in .44 magnum and lesser rounds is provided by neck tension and not crimping. The crimp in those revolver rounds is the last line of defense not the first in preventing bullet movement. The sizing die and expander work hand in hand to accomplish this. The sizer must reduce the case diameter with all brands of brass to the point that an expander is necessary to increase the case I.D. slightly. Then an expander which is at least .002" smaller than the bullet diameter is used to open up the case I.D.. In heavy kicking rounds the expander might need to be .003" smaller than bullet diameter. Not flaring the case mouth is not a substitute for proper case neck expansion.

Bruce