This is indeed a very interesting concept! I will try with my 444. I wonder if the shot cup does any better?
Even with Micro-groove rifling, a plastic shot cup will make things worse. It will turn the 'donut' pattern into an 'inner tube' pattern.
You're better off with nitro cards, fiber wads, and over-shot cards. But, it still isn't good for much beyond about 15-20 feet. The velocity is just too high, and the shot has too much time to rotate while traveling down a rifle barrel.