RE: Case bulge 45-70
Not really knowing how big your chamber is to begin with, a bulge of .005 from a virgin brass case may not be as big of a red flag as it is normally would be. But I would still be concerned . . . and would personally drop the load back to a level where this isn't happening. On my rifle, I also got a bulge at the web before the primers showed anything alarming. It made me wonder if that Marlin bolt was springing a little under pressure.