The Dillon super swage is the best solution to swaging primer pockets, i’ve done many tens of thousands over the years using different methods and nothing else compares.
The seating bar you mention can seize up. Back off the screw and try and work it up and down till it’s free.
Once free, only lock it back up when a case is in the swage position.
Page 8 here http://dillonhelp.com/Dillon%20Manua...l_may_2007.pdf