That is a misleading statement.

You can NOT size the NECK completely without also sizeing the body of the case with a fl. size die. In fact, most times you will size quite a bit of the body if you size much of the neck at all!

What you CAN do with a fl. size die is,to set it toNOT push the shoulder "back" and only "partial size" the body of the case by ajusting the fl. die so it "doesn't" size the full length of the neck.

To only size the neck, your better off with a seperate die of your chooseing.

Drilling Man