The good thing with the bailey, it's a class 15 bobbin and bobbin case. I'd also suggest asking on the vintage section because many folks there have done a lot of work on class 15 machines, and may know what will cause it to get jammed up with thread underneath.
BTW-both my husband and I think the bobbin case does not look correct. It appears to be going too far back and not hooking into the slot like it should. My husband thinks that looks like a Bernina case.