Rich, have you tried to push/force the ring around the collet back down ? They do take some grease occasionally. Maybe go over to
www.shotgunworld.com and on their reloading forums are a couple of guys who " wrote the book on Mecs ". Not really, but it seems like it. They are very strong on Mecs and there are many guys who could help. Curly even has a couple of stickies on fixing them.