Nice shot. At that range, he probably didn't even notice the sound of the shot. And yes, all of the things you mentioned (altitude, barrel length and several other things have an effect on MV. I shoot a 35 Whelen, which I use to make shots to 700 yards, and I don't doubt there are those who would say its a bad round for distance, too. However, it hits like a hammer at distance, and makes an entrance hole that's about .37 caliber. Exit holes are much, much larger. And most animals won't react to the noise of a shot if they are at a distance. They don't attach it to danger. I've shot deer at 400 yards and more and had the herd just mill around or even run towards me and stop. If they don't see you or smell you, sometimes they'll just stand there and die without reacting to the sound or the hit. The sound comes significantly later than the hit and they don't make the connection. Again, good shot. But back to the question posed in this post, about best under 500 yards. I'd still go with the 30-06. Why? Because I just like the -06 for its combination of range, bullet weight, selection, availability, effectiveness, versitility and penetration with the heavier bullets. Oh, and I just like the -06 because.