Not sure if all things are equal but I had to use .44 mm rings to get the sweet 22 off the barrel of my XT22VR . Rings suitable for a 40 mm objective were too low .
Just bought the same scope and purchased Leupold High rings, part number 55870 from gander mountain. the front of the lens barely makes contact with the rifle, so i will also be needing taller rings. Online these rings say they are 1.15 inches tall. Leupold Stevens Rifleman 1.15 Rings - Gander Mountain