Broadside
Follow the back edge of the near front leg up to a point about one third of the way from the bottom of the chest to the top of the back, not counting the hump. The heart sits just above the elbow. A bull's long shoulder hair hides the leg line, so pick it out where the hair thins toward the knee.
Quartering and other angles
Quartering away, drive the bullet toward the far front leg through the soft ribs. Quartering to, the shot has to go through a massive shoulder joint and heavy bone. Only take it with a bullet built for deep penetration, and only if you have to.
Do not
Do not aim at the centre of the visible mass. That puts the bullet above the lungs, through the hump and spine processes, and lets the animal walk off.
Where they live and the typical miss
Hunted on the Great Plains, in Alaska and on managed ranches and reserves. The typical miss is high through the hump, followed by a short blood trail as the bison walks off unconcerned.
Bullet choice
Plains bison hide, hair and bone are much heavier than elk. Use premium bonded or monolithic bullets that keep their weight and give an exit wound.