I have used those dies and they will roll crimp if properly adjusted BUT: there was another thread recently about some guy who bought a set and had a problem because they placed the wrong die in the set at the factory. So we need to rule that out first. Are you attempting to seat and crimp in one operation? I seat the bullets first and then back the seating plug back out and then screw the die down until it starts applying a crimp and then crimp all the cartridges. Trying to prevent bullets pulling under recoil by using heavy crimps is a waste of time. The crimp does almost nothing to hold the bullet in the case. The neck tension is what holds the bullet in place. If the expander plug is not at least 3 or 4 thous. under bullet dia. it is over expanding the case mouth and the bullets will not stay in place. If you seat a bullet (with no crimp applied) and press it hard against the edge of your bench you should not be able to push it deeper into the case. Any at all. If you can move it, you need more case neck tension. If you cannot move it the bullet will not pull under recoil. The expander plug can be turned down in a drill press until it is the correct size. Once you achieve sufficient case neck tension crimping only serves to remove the flare you put in the case and leave a light crimp. Using heavy roll crimps will only work harden the case mouth and cause it to split. When you seat a bullet you should be able to clearly see the outline of the bullet and where its base is just by looking at the cartridge. I didn't make this up, this is how Elmer Keith explained it in his book. And he was right. I have been reloading .41 Mag ammo with heavy bullets and heavy charges of 2400 for twenty years and I have never had a bullet pull and I am still using brass from 1987.