Not sure I should own up to this, but ...I've heard my share as well. But when you shoot a lot and I mean a lot now and then you'll get that 'Lucky shot'. And in most cases if you don't have a witness nobody would believe you.
I had an 'era' where I hunted hogs with 22 mag using only head shots. Did okay but missed a few. Hogs seldom stand still like deer. And almost always have their head moving.
Then got into deer hunting with my .44 rsb. First year I was pathetic but a lot of off season practice got me on track and I actually started making some heart shots over time.
Well, after some seasons had an opportunity at a smallish 6 and dropped him in his tracks. Drt. Gathered my gear, walked out and not a hole to be found in the hide. He was however now a 3 point. Entry hole was perfectly in ear, and exit obliterated offside antler.... Never to be found.
Must have missed by 2 feet! But what a shot it would have been on one of those hogs!