I just bought a Vortex Cantilever with a 3" offset. We'll see how it works out with the Hawke Endurance. Weaver Tactical Rings weren't going to cut it.
I have used Burris PEPR, both the QD and the standard variety. Good mounts, just a bit heavy. The Nikon mounts were fine as well. All my 450 BM builds have been getting the AERO Precision Ultralight mounts and I would suggest going that route if you can do without the QD feature.
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