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I use a Nightforce NXS 5.5-22 x 50and have used it to shoot out to as far as 1800 or so on steel. I really like the scope. The glass is good, the turrets track exactly as they should every time, and it has a solid zero stop. It is also really durable, but heavy. My family members that also shoot distance use Leupold VX-6 HD 4-24 x 52 scopes. They really like theirs and they are lighter than a nightforce. I haven't played with their tracking, but they haven't had any issues with theirs.
Nightforce scopes are awesome. If you don’t want to break the bank, look at their SHV series. I run 4 of them and have absolutely no complaints. Very reliable and well made product!! My next will likely be an NX8.