i have 3 nef guns, and found out that if any oil or liquid or anythign is in the chamber it usually will cause a stuck case, i cleaned and made sure they were dry when i was done, but a day after there would be oil all over the face of the reciever..i thought to myself, what the heck, and remembered i oiled the extractor, i took the extractor apart, well its an ejector, but u know what i mean and dried it, oiled it very very lightly so there was no excess oil, reassembled, the problem was fixed, i no longer had stuck cases, its worht a try to dissassemble the ejector area and check it out, the oil would always get in my chamber and cause stuck cases 100% of the time, but you might have a whole different problem, but i guess its worht a try to check it out...hope u get your gun working right...