Hi Scott,
I went through the same thing with my Redding die set for .40 S&W. I called Redding and essentially got the same answer as in the FAQ - the carbide ring inside the die is there to size to top part of the case. Tech support's suggestion was to back off the die (in my case 1 1/2 turns out from contact with the shell plate) until there are no more 'rings' around the bottom of the case.
Redding does make a dual ring carbide sizer die for .40 S&W that should, theoretically, eliminate the problem.
http://www.redding-reloading.com/index.php?option=com_content&view=article&id=124:dual-ring-carbide-dies
Cheers,
Oliver