hatsan conivore

I Wanted something backyard friendly so I bought a Hatsan carnivore in .177 to take care of rodent problem. The preferred pellet is predator polymag. So far I've taken out 35 rats. Now I'm in a new house and there is a house sparrow problem. But not for long it Just turns them into a puff of feathers. If anyone is thinking about getting a conivore its a great gun just heavy and it takes a good bit of effort to cock.