Re: Scope advice
The -16X has about 50" internal adj, it's pretty close but it should be suffice for the 500 yards shot. The -24X internal adj will be ~half that of the -16X.
Magnification wise, it depends on your eye sight. There are folks here that are very capable of taking shots beyond 1000 yards at 15X or less. Unfortunately, I am not one of them, I need as much usable magnification I can get/afford.
40 or 50? Again, it's a matter of preference. IMHO, 40 is plenty but I'd get the 50 for that extra advantage ... I need everything that can augment my eye sight. The 50 will require a higher cheek weld.
As far as base and rings, I'd go with mkg recommendation (esp. the Burris with inserts) but go with Russ Hatch's 20 MOA recommendation.
Good luck and happy safe hunting/shooting!
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