Well I am not really up on the science of shot guns but my friend and I got some 28 gage power pistons and loaded them in our 54 rifles and broke some trap with them my friend always carries the stuff with him we have some squirrel hunts at our rendezvous and he uses shot in his 54 so they are still edible. I wish I could give you more info but we never worried about patterns and stuff we just fill a mag power piston with seven&half shot stick a wad of toilet paper on top and push it down over 80 grains of pyrodex RS, I would guess black would do well also but it is hard to get here.