Is it just me or does the PPU case look like it has an ever-so-slightly smaller diameter at the rim??
Break out a Micrometer, if you don't have one, GET ONE...they're Invaluable when determining rifle issues and tolerances...
B'sides, they're only $10 at Harbor Freight Tools
Anyway, take multiple measurements and see what you come up with...
It could be something as simple as the extractor not getting a proper grip on the case...
or a worn extractor that can't get a grip on a smaller diameter case...as .01 can make all the difference in the world
Marlin had an issue with the 2005-2011 Marlin 60 & 795's accessory rail...as it was supposed to measure .43" wide...
yet many were coming out with .44"-.46" widths...which meant the pic rails that were tuned to the .43" specs didn't fit...
so .43" to .44" can make a difference...do I haveta make a One Red C-Hair joke here??