Below was posted on the Dillon Forum
I am having problems with the primer being reseated in the case. I have tried all suggestions. I have reloaded tens of thousands of cases before with no problem. I am using Dillon brand 9mm dies. I have changed the anvil, polished it, and even polished on grinder with no help. Having problem with all brands of brass. The only thing I can think of is changing the spring or entire punch assy. Is the spring available separately or complete punch assy without buying new dies?
And here is a reply
had same issue...contact dillon and they will send you a new style primer seat assmbly that you can actually take apart to change spring once worn out. The old style is a bitch to try and disassemble....best wishes.
Hope this helps.