Like me, others have complained of case neck splits with this cal with their reloads. And like me many use the Lee dies so I began with a letter to them. Truthfully I didn’t suspect the seating die was at fault until after reading their response telling me that bullets being seated slightly canted can be blamed on many other procedures. Studying the engineering of the product and comparing to the competitors products it became clear that with their floating centering device that must do so at the top and bottom simultaneously while not being supported anywhere, that this design solved a problem that doesn’t exist.
The solution came when I used the seating die I found in my 300 Savage die box, turned out to be a universal 30cal “KRUPP” American die with a truly floating, sliding and guided sleeve to center both the bullet and case mouth while seating.
Problem gone and my loads are perfect and this also explains why my 38Super loads had the same problem. I still like Lee loading products, just not the seating dies.
Hope what I have learned will be helpful.
Tom
