I'm looking at the gun now and I think that I see what you're talking about, Jim. Here are some pictures - let's see if you agree with what I think that I'm seeing.
Here's the case at the point that things get stuck. This is the left ejector
Here's the right ejector
Here's the left ejector with the action open
So, it seems to me that the rim is hitting the very start of the left ejector just a tick before the right ejector, then binding up between them. At that point, the mouth of the case wants to flip up, but it's still partially in the breech and can't pop out unless it's really manhandled. Then it looks like this:
That's the result of being ejected five or six times. One ejection leaves a peak and two divots, matching the front of the ejection port.
I guess that the proof is in the pudding: if I loosen the ejector screws slightly, the round pops right out. Is the solution to put a dab of locktite on the screws and put them in until they just snug up?
FWIW, it also looks like the diameter of the rim is critical. Just a hair big and it'll jam up. A bit too small and it will be fine. Maybe mine are a tad on the large side. It's a little late to go digging up my calipers, so I'll save that for another day.