Lumbajak wrote:600 metres is a looong shot on a living creature.
Personally I would like to be sure of 1 Moa accuracy in the field in any conditions to achieve this on any animal.
Even a half-MoA rifle doesn't guarantee clean kills at long range.
A 1MoA rifle will drop its bullets into a 200mm circle at 600m - meaning it'll hit somewhere within 100mm of your aim point.
With a high-BC bullet - like the Hornady 220gn ELD-X (BC .650) - at 2300fps from a .308 with a 200m zero, you have 3.4m of drop at 600m. Even if you dial the scope in, misjudge the distance by just 10m short or long and your 200mm circle is 250mm above or below where you want it. Add a full-strength 10mph wind and your 200mm circle is now 250mm high or low _and_ 900mm off to one side. At 600m the bullet is doing 1540fps and carrying 1160ft/lb of energy.
Put that same bullet in a .300WinMag with 400fps more velocity and you have only 2.4m drop and your 10m range mistake reduces to 150mm over or under, and the wind reduces to 700mm. And it hits at 1850fps with 1680ft/lb of energy
Go to the .338 Lapua with the 270gn ELD-X (BC .757) at 2800fps and your 10m error reduces to 120mm high or low and your wind to 540mm. Velocity is stil 2050fps and you have 2520ft/lb of energy making a near miss pretty damn fatal.
Long-range shooters like the WinMag and Lapua because it allows them to make the hits.