I know this has been beat up, even by me, but can someone tell me:

If you have a .223 semi auto capable of hitting sub-MOA out to 600 yards (I do) and you were hunting southeastern deer not getting any bigger than 180lbs...

What would be the absolute furthest you would shoot a deer, and what bullet/round would you use?

Here's my issue. Where I hunt in SC there is one stand that has about 3 shooting lanes that go out to 150 yards max. I'm not concerned about this. A second one has a maximum range of about 350 yards. This affords pretty good cover and if I see a big buck I can get out of the stand and get a bit closer if I have to.

But the last one is almost 600 yards. I know a .223 isn't wise that far so I'm just curious how close I can get and still make a clean kill using a .223 assuming I get a perfect vital hit.