I have an older CZ550 in 458WM with the hogs back stock. With Warne QD mounts, the rings are 5.110 inches (just under 5-1/8") outside to outside. The rings are set as close together as seems reasonable. My mounts put the bottom of scope tube .430" above the top face of the dovetail which leaves about .080" minimum clearance between the eyepiece and bolt (eyepiece is 1.560" diameter. The front mount is entirely on the flat of the dovetail but could be squeaked back maybe .100" if you're ok with it partially over the radius at back of the dovetail. The rear mount position is fixed by the recoil lug. Hope this helps.