Another item to consider in the FTF (Failure to Eject) / Stovepipe issue is the Extractor and / or its Spring
If your Extractor isn't holding the Case Rim tight enough, the Ejector can't kick the Case around and out of the Ejection Port
22s being the dirtiest Round out there, it's easy for crud to build-up behind the Extractor and hold it out a bit
OR, the Extractor Spring can just get week over time