Hmmm.....not likely anything is worn, because the gun isn't that well-used. The problem has been intermittent, on some days it works fine and on some days I want to throw it. I've been careful to oil the recoil tube and also the area where the bolt slides in the receiver, but haven't paid particular attention to the ejector plate. That might explain the 'hit and miss' nature of my cycling problem. Now I just have to wait until my next venture out.
Thanks for the idea.