It looks to me as if you have two separate issues, one is mag related and the other is a failure to extract/eject properly.
The ejection issue is quite likey caused by the extractor, not only the pressure of it is influencing extraction and ejection but also its shape and how far it reaches over the rim.
You can either replace it with a Volquartsen (sp?) extractor or relief the extractor yourself.
I filed mine down a tad, so that it could reach over the rim better and the rifle runs very well now, before that I had about 30 to 40% FTEs.