I'm quite the non expert. Where I hunt you can find elk at the long range. However, last year I took mine at 35 yards
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. I used a 300WM and 180 Partition. .30 in and .30 out in between was a mess though. So don't discount the close range effectiveness of your choice. I have no doubt the Scirocco would hold up, but no experience.
If you are new to the mountains I would try to borrow or own a range finder. I really used mine a bunch the first couple of days to get a feel of the ranges. Easy to missjudge in the 400 to 550 ranges as being a far poke but doable. I really don't want much to do with 400 myself.
Oh, get that one trip thing outta your mind, won't happen. You will take a PT job at the Stop and Rob before you miss two in a row.