Don’t forget that buffalo hunter William Dixon killed a Comanche warrior at 1,500 yards with an aimed shot during the Second Battle of Adobe Walls while using a black powder Sharps buffalo rifle.
Several hundred feet short of a mile with an aimed shot. If it wasn’t made from a high perch over a canyon , I would doubt the validity of the story also
It was the afternoon of the third day of the battle when Dixon spotted a group of Comanche on horseback gathering together. He fired twice and missed, but his third shot found it’s mark. There are a number of BP shooting clubs in the US and Europe who hold annual contests to try and reenact his shot.