That's a hard question to answer because there are a lot of variables to take in to consideration while shooting extended distances. From personal experience, I shot with a friend who uses this Vortex Razor HD Gen III 6-36x56mm Rifle Scope and he has used it to shoot 800 yards. Here are some guides that give more information into long range shooting and rifle scope selection:
https://www.opticsplanet.com/howto/how-to-start-long-range-shooting-on-a-budget.html
https://www.opticsplanet.com/howto/how-to-choose-a-riflescope.html
Absolutely! Look for a 1-piece picatinny rail mount, and a pair of our Precision Matched Rings, 34mm, 1.1" height!
These Vortex Razor HD Gen III 6-36x56mm 34mm Tube First Focal Plane Rifle Scopes have a max elevation adjustment of 120 MOA and a max windage adjustment of 52.5 MOA.
Please email us at techsales@opticsplanet.com regarding your question.
This can depend on the type of rifle you intend to mount this scope to. Spuhr makes very durable cantilever mounts as well as Scalarworks and American Defense Manufacturing. Links to the mounts I recommend can be found below. You can also email us at Techsales@opticsplanet.com and let us know what specific rifle you intend to mount this scope to as well as a budget you had for the mount, that way we can more accurately recommend a scope mount that will work best for your setup.
https://www.opticsplanet.com/spuhr-34mm-cantilever-riflescope-mount.html
https://www.opticsplanet.com/american-defense-manufacturing-2in-offset-1-93in-top-of-rail-to-centerline-yuujc.html
https://www.opticsplanet.com/scalarworks-leap-scope-mount.html
The Vortex Razor HD Gen III 6-36x56mm Rifle Scopes are in stock and available for purchase. Inventory changes very quickly so their availability may change soon.
Yes, the 34mm diameter Vortex Precision Extended Cantilever Mount with the 20 MOA cant should work for the Vortex Razor HD Gen III 6-36x56mm Rifle Scope on an AR10.
To mount the Vortex Razor HD Gen III 6-36x56mm Rifle Scope to an AR I recommend using the the mount listed at the link. It should give you enough clearance for the objective lens.
https://www.opticsplanet.com/vortex-precision-qr-extended-cantilever-mount.html?_iv_tube-diameter=34-mm