Good choice for the long range stuff (300 WM) my 300 wm has a 4x16 Vortex HS and find it fine and reliable which won't break the bank ( bit over a thousand these days)
I think some of the cheaper high magnification scope when using them at over 20 power can get a bit fuzzy and that is where the more expensive brands come into there own.
I have only shot steel at long range and don't think I would take a shot at an animal at around 600 yards unless the conditions were right. 600 yards is a bloody long way in my books .
I would be inclined to use at least the 200 gr bullet in the 300 WM for long range shooting. I use the 200 gr ELD X and RL 26 powder for about 2900 fps.
Plenty of practice will get you there, and start shooting at animals at 300 then 400 yds as your confidence in rifle, reading the conditions and your personal ability and you won't go to far wrong.
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