Do you have any other bullets you can try seating? I'm still kind of thinking it is something to do with the die's. Is it possible you may have the wrong expander in the resize die?
And is the resizing die adjusted all the way down to where the shell holder is making good contact with the die at full stroke, linkage popping over in other words?
You mentioned something about adjusting the die every which way you can. And also said you trashed a bunch of brass because of this. To my knowledge, a resize die will never damage brass regardless of how it is adjusted. It will either resize the brass if adjusted properely, or it won't if not adjusted accordingly. A long time a go friend of mine was not adjusting the sizing die down far enough, and had the same issue your having.
I'm sorry for the inquisition, but there is so much of what your saying that contradicts the proper adjusting of the dies, the sizer will deffinitely not trash brass unless you forget to lube, which isn't apparent.
Does anyone have a video to post that will demonstrate the correct set up for both die's?
I hope you can get this figured out, it's got to be pretty frustrating. Fortunately there are a lot of seasoned reloaders here to offer their expertise. This will proably turn out to be one of those once in a life time circumstances none of us thought of.