Good point chewy. I mounted a Bushnell Banner 4-12x40 on my Axis using the original rings that came with rifle mounting the Weaver 3-9x40. I had to replace the two-piece bases with a one-piece multi-slot base because the tube on the Bushnell is shorter as the objective bell starts to increase in diameter earlier. I was just able the existing rings. If eye relief would have been a half inch shorter, I'd have had to use taller rings.