I think most of us loaded AA hulls beyond their useful life back when. I'd load them w/AA452 until there was almost no mouth left and what was, was both split & burned & they still broke correctly pointed skeet targets. No argument here about that.
Empirically, I observed that reloaded hulls using the Ljutic Mono Wads cut from some form of fiber board [I think] would grab the inside of previously fired AA hulls like they were super glued upon firing and stretch the hulls over 1/8" w/boring frequency. Those same loads almost always ironed any fold memory from the hull's mouth & when viewed from the side the hull's mouths were clearly stretched in a non-uniform manner. Some of them were off sounding on occasion as well, not always, but the hull stretching was. Same loads in a paper hull [Winchester, Federal or Remington] never exhibited that issue or sounded 'off'.
There was an article several years ago where someone had tested for pressure differences with differing crimp depths and found significant increases with increased crimp depth. I don't recall who wrote it or where it was published, but I remember it caused quite a stir at the time & I still see refs to that effect. Testing was done by an independent lab for the author. I do not believe there was much velocity dif. noted. and that it was done using once fired CF hulls.
Just saying.
Conventional 'card' wads? I'd not think they contribute anything significant to pressures generated.
