G'Day. This is my first post.

There are a few that come to mind, but this stands out.
I was prone on a 30 ft high bluff overlooking the Zambezi shooting at a croc about 80-100 yds away at the water's edge. Rifle was a Ruger 416Rigby with a Harris bipod that the PH had the foresight to bring along. Ammo was handloaded 400gr A-Frames.

He was quartering towards us as I lined up for a brain shot. At the shot, the tail went to flapping like a banshee, water spraying like geysers. I heard the PH say, "In the shoulder, in the shoulder!!". So gave him another at the junction of head and body. That stopped all the commotion!
Detailed examination revealed the first round entered right where I'd intended. a few inches in front of the right eye. The top of the skull, between and behind the eyes, was now hinged like the top of a cardboard box.

The first one did the job, but as long as the tail's still moving you run the risk of losing him in the water. He taped out at 13' 4" even with a piece of tail missing.