We have done this before. For big game I have shot moose, bear, elk, deer, caribou and antelope over 1000 yards with 270, 7mm, 30 and 338 caliber rifles chambered in several cartridges in each caliber. Longest was 1340 yards on a mule deer near Alder, Montana with a 300 wby mag in the 1970's. I gave the exact distance on the other thread like this because I looked it up in my notes. Shooting from the hip now but I am sure it was 1340 something.
Mine is on a Antelope last year. It was 1200 yards when I pulled the trigger, and it turned on me. I was shooting a Desert Tactical Arms, SRS in .338 LM shooting a 300 SMK. the bullet grazed the ribs and hit the front shoulder and she droped. I looked at her and i could see her head up, so i put one more in her as she laid there then i saw her head drop.