This is kind of like asking what rifle is best for deer hunting. A lot depends on where you are, how far you shoot, how big the target and, of course, how much you want to spend. For an all around economical, hard hitting, accurate rifle, it's hard to beat the Archer Arms QB-78. They are easily tuned but pretty good right out of the box.
Co2 cylinders do add to the shooting cost, but you can put one full and one empty into the gun with no loss of velocity, just fewer shots. And they are not so good when the weather gets cold.
Spring piston airguns are more economical to shoot, but need a light, consistent hold to achieve best accuracy. Keep in mind that advertised velocities are mostly BS, and shooting a pellet much over 1000 fps means it is transonic. This makes it
MUCH louder and not nearly as accurate, as the flight path is disturbed when it goes subsonic a few feet from the barrel. Does this matter? Depends on whether your target is at 12' (probably not) or 30' (definitely will).
There's an excellent air gun blog affiliated with Pyramid Air; much good info there and hours of reading old posts. It will cost you money if you read too much, though.
Joe B.
