this bullet sounds like a Winchester Silver Tip used for varmint hunting.
at hyper velocities, hitting something like steel it should make a hole straight through, since the steel tensile strength could prevent the bullet from flying apart like a grenade , while making a hole.
on the other hand, shooting at soft bodies, there isn't anything to confine the bullet on impact, and it should explode like a grenade.
I might be wrong, but it is what it sounds like to me.
yes I use Winchester SilverTips, when I go hunting. (94 Winchester Lever action .30-.30 )
praticed and tested on a gallon sized milk jug full of water. results , on front side not much damage other than the one small entrance hole.
on the sides, top, bottom, and back of jug, never found them. blew those sides to complete shredded nothingness.