It would need a lot more power.

You just need to do the math on these. Using shot it puts out about 12 ft lbs at the muzzle, that's with 20 #9 pellets. Now since they have such little mass, they are going to lose velocity very quickly. Also, they're not all going to hit. So if you figure that at 10 yards they've probably lost at least 25% of their energy and that only a few of the pellets will likely hit, it starts to give you some idea of just how little energy you're working with. Assuming 25% energy loss and 1/3 of the pellets hitting, you're talking about 3 ft lbs of energy hitting the target at 10 yards.

But there's another problem here as well. #9 pellets moving at maybe 475 fps are going to have very little penetrating power. For hunting purposes, I'm not sure if they'd even break the skin.

I think the thing to do with a gun like this is just accept it primarily as a toy.