What's the big deal CC? You can make the weapon viable by not forcing it to a certain role, look how well grenades come into fights, like not at all? And they are like almost only CC based.Balance the shotguns CC capabilities, damage, fire rate etc. etc and profit. There is place for them to do CC(knock-backs, knockdowns), do decent damage and have better than average fire rate, that all is compensated for its range.That's it, you don't need anything else to make the weapon viable, you don't need new ammunition, you don't need to make shotgun a pure CC tool, because there is space for something more and you certainly don't need to re-invent an existing weapon to some type of new grenades.