How much experience did you have on the rifle before this shot?I'll provide my recent personal experience. I shot my first bull elk this year at 800 yards which is much further than I had hoped to shoot. However, there were a few key factors that played into that decision and leant me the confidence to take the shot:
1) Earlier in the week, I shot a vital sized rock on the same hillside from the same shooting position at 750 yards and scored a first round hit. That provided proof positive that, at that moment, my equipment and skills were capable of making a hit at that range.
2) When I was presented a shot opportunity, it was nearly ideal conditions: the elk was very calmly feeding on the hillside and not moving, there was essentially zero wind and I was fully prone shooting off a tripod with a rear bag.
3) I had a Tikka 6.5 CM in a RokStok
All of those factors combined to give me the confidence to take a shot that I knew I could make even if it was further than I expected to shoot. I was rewarded by watching my bullet drop right into lungs and recovering the bull.
I will also note that earlier in the week I had a prior opportunity at this same bull but I passed at 700 yards because I was shooting from a seated position on a steep hillside off of trekking poles. I got crosshairs on the animal but with the position and heavy breathing from the scramble to get into position I knew it wasn't an ethical shot so I let him walk. That was an unbelievably difficult decision to make because it was my first time having an actual opportunity at an elk after several hard years of hunting and it was getting to the end of the trip. Even if I hadn't gotten my last second success I would have been glad I passed on that shot rather than risking wounding an animal that I never would have recovered.
All in all, range is just a number and it's specific conditions that dictate ethics.
How many hits on a vital sized target with this rifle at under 300 yards, how many between 300 and 600 yards, how many between 600 and 1000 yards?