Shot cup petals should "Never" extend beyond the shot, better to be a bit shy. When the petals extend beyond he shot they are encased in the fold of the crimp, whether roll or pie. This presents a very real possibility of the wad being retarded before the crimp can open. There is then a distinct possibility of Max camber pressures being increased, perhaps to a dangerous level. There is a very good reason wad makers keep their petals a bit shorter than for the intended shot load they are designed for. I didn't dream this up, it came from a ballistician in a ballistics lab, just don't at present recall the lab.
