One day I built a bullet seater, I built it without a die body. The plan was to center the bullet with the case neck with support.
And then there are tools that bevel the inside of the case neck and bullets with sharp edges on the base. In the old days Herter made a seating die called 'universal', the die body had a slot cut into the side of the die body; the slot allowed the bullet to be dropped into the bullet guide while it set on the case neck.
And now I have RCBS Competition and Bold Medal seating dies with the same concept.
So what happened? The bullet hung on the neck of the case and pealed it because there is no support for the case body, neck or shoulder when seating a bullet.
Most seating dies are designed to have the bullet placed on the top of the case neck; reloaders assume the bullet aligns with the neck, some bullets tilt and then straighten when the ram is raised.
F. Guffey