I have one of those scopes...Its not to bad for the money and I have made some long shots with it, 286 yard cold bore shot on a p-dog, 288 yards on the second shot another p-dog just of the mound the first was on. Mine is on a 6x45 AR-15 though.....we ring the 500 yard gong at the range with that rifle and scope. I havent pushed it further yet but the adjustments are soild.
Also have the 3-9x mounted on a 22. Both are pretty nice scope.
Once you get it zeroed be sure to move the turrets to zero, that way you can just spin the turret for the range you want and then back to zero for your orginal point of impact.