Der Ami, I ultra sonically cleaned the action and the parts. I removed all the parts and polished off any high spots or burrs. It isn't related to the ammo or primer seating.
It isn't the spring because it fires the shell just fine after firing the left bbl first. I am truly stumped.
Maybe the right firing pin is dragging on something when the left firing pin is cocked? If it only happens when the right trigger is pulled first, then something related to the left trigger or left firing pin (when cocked) is preventing the right trigger/right firing pin from hitting the primer hard enough to fire the shell.