all I have to say is a fast moving object flying through the air such as a bullet, its stability can be nocked off quite easily, and yes they will do the strangest of thing when hitting an object. The strangest ive seen was a 150 grain winchester power point shot from my 30-30 at a doe from about 50 yards the bullet didnt pass all the way through when processing it i found the slug lodged in the right shoulder mushroomed backwards the nose was still intact somewhat but the base was mushroomed, weird i thought how do you explain that I would imagine the bullet hit a twig or branch before it hit the deer and begun to tumble just as it hit the animal.