You may very well need a new scope, but before you get one check the bases and rings. I bought a Tikka T-3 and used the factory Tikka rings to mount my Nikon Monarch 3-9x40. I couldn't get it zeroed for anything. Knew it wasn't the scope. Ended up that the scope was sliding in the rings. I switched to Leupold rings and bases and haven't had a problem since.