advice wanted: shots landing below target

Your $90.00 gamo scope should be okay to use on that gun. you have the 1000 fps version right? the recoil on that shouldnt be enough to brake the scope. Your scope will have some weight to it so when you mount it to the gun it will reduce the recoil a little bit and you will find it a little easier to shoot.

The thing you must understand with sighting in and zeroing your sights (both open and scoped) is when you fire the gun the pellet does not fly in a straight line it curves up then drops lower again. If you zero at 20 meters you will be shooting low at 10 meters and if you zero your gun at 10 meters you will be shooting high at 20. Find the right pellet that the gun likes and then take the gun out into the field and see how far you want to shoot..zero at that distance then move in closer and see where the pellets are hitting so you know how much hold over you will need for your closer targets or find a distance in between the two that you can zero and not have that much hold over. I normally zero mine at 29 yards that gives me a good range to point and shoot bunnies. if im going possum hunting i will just stand under a tree and shoot at the leaves on the tree and zero it again from there.

Hope that helps.

I spent an hour or two last night with the Gamo Scope installed. It is a massive improvement on the open sights. The rifle is almost hitting spot on, tonight I will try it further out at about twenty meters without altering the scope and see if it improves POI. thanks for the advice.
I read about a Leapers one piece Shock mount, Pauly5 do you have another cost effective recommendation? now I know the Parrus is hitting the target it may become my no.1 go to and I can semi retire my two older rifles. (S&W 77a and a Sheridan CO2)
And a big plus is the arm work out it gives you when cocking it, loads of fun to be had.

Nice!!