If you're shooting at 500-800 yards and your target is smaller then say, a semi trailer you're going to wish you'd got at least a 18-25 power scope. Anything less powerful and the crossed hairs or mil dot is going to completely cover any standard target- no chance for zero'ing in on the bullseye.
When Banjos are outlawed, only Outlaws will have Banjos
The Bible is my lawbook. I turn the other cheek when applicable, and spend the rest of my days resisting evil at every front, until I have breathed my last breath.