I'll just echo this if I may.
Having "a rifle and scope capable of -FAIRLY- accurate..." is only about 20% of what's required to be in the killzone at those ranges. And what kind of impact energy will your 175 be delivering out there?
And then how are you going to recover the animal shot?
You should be able to get a reasonable estimate of distance by your compass and topo map surely, how did you "guess 600" ?
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