This question originally appeared on Quora.
Answer by Rory Young, 23 years in wildlife management, forestry, and the safari industries as a professional safari guide, ranger, tracker, owner, and manager:
I will answer only in terms of self defense against a charging cape buffalo. This assumes there is no option but to shoot as the animal is in a full charge, that you are armed with a .375 H&H or larger and that there is no good tree next to you to climb.
The cape buffalo kills more people in Africa than any other mammal after hippos. It charges at approximately 56 kmh. Shooting it through the heart in a full charge will not necessarily stop it in time. I have seen a buffalo run 80 meters after being shot through the heart. (see. Therefore, the only way to stop it dead is to shoot it in the brain. The brain is 12 cm in diameter.
Because it is moving toward you at 56 kmh, the brain is only 12 cm in diameter and the head is moving up and down, it is best to wait until it gets very close and drops its head to gore you. This is usually when it is 10 to 20 meters away.
You need to hold your nerve and shoot perfectly accurately. If you miss, you are dead. If you turn and run, you are dead.
Unfortunately for me, I had to do this twice in one day in 1993.
I was together with another ranger-guide, Jesse. We were investigating reports of two "problem" buffalo in one of theareas near and had been warned that they were injured and had chased a couple of people up trees.
Unfortunately for us, they had moved into jess bush, a type of very thick thorny vegetation. It is a common tactic for injured buffaloes to take refuge in dense bush, and it is extremely dangerous to pursue them in such areas as they are extremely aggressive, have acute senses, are very cunning, and it is almost impossible to move quietly through Jess (it often involves crawling).
However, it was our job and we had no choice but to go after them so in we went.
The first one came flying at us through the jess and came out into a small clearing about 20meters from me. It dropped its head to hit me at about 15 meters, at which point I shot it.
We found the second one about five hours later in a much bigger clearing. He was on the other side of a small valley, about 80 meters away. This is far to shoot with a heavy caliber rifle and open sights and normally would not be done because of the chance of wounding. I gave the go-ahead to Jesse to shoot, though, because the animal was already injured (meat poachers had tried to kill both animals causing the wounds), dangerous to the local population, and surrounded by jess bush, where it would be more difficult and dangerous to find him.
Jesse fired, and the bull took off for the thick bush heading diagonally away from us. I sprinted after it because I really didn't want it going into that jess.
The bull caught my movement and veered round to charge at me. I stopped and prepared to shoot once it got close and dropped its head.
Instead, it fell to the ground about 20 meters from me. I lowered my rifle and just then Jess fired another round to make sure it was dead. Instead, it got up again and came at me a second time. By the time I raised my rifle and aimed, it was only 7 or 8 meters away, so when I fired, even though my shot placement was spot-on, the momentum of the charge carried it several more meters and it literally ended up at my feet.
I never had to shoot a buffalo before or after that day in self-defense and ever since have not followed buffalo, wounded or healthy, into jess bush.
I reckon, if I do it might be third time lucky for the buffaloes.
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