Ed~Been gone for a few days, so I'm sorry for the tardy reply. I ran the numbers again with 320gr of powder and the recoil starts at 154 ft-lbs and goes up to a bit over 200 ft-lbs. Lots of recoil!! I'd love to shoot that thing if I was ever in the area.
What modifications were made to the 210 action to make it feed and eject those monster cartridges?

If at first you don't succeed, keep on suckin' 'til you do succeed. ~Curly Howard