That's like the gun my little brother has....he hunts squirrels and birds in my neighborhood on a regular basis. It's works pretty damn good....he's shot that thing so much and is such a good shot you'd think it had a scope on it.
I had a Crosman something or other that used to take out birds pretty well, then I just stopped shooting it and never bothered again. Still have it somewhere though.
Where I used to live I shot at birds and animals so much with my airsoft gun that after 2 months birds didnt land on the wires behind my house. I let them be now...