Nope, never lost a petal yet and all had perfect expansion about the diameter of a quarter. I even shot a watusi in hondo a year ago right thru the skull. Perfect looking bullet on that as well. I have the skull mount and they had to use about 2? of filler down thru the skull. Bullet blew out a trench of bone. And the first cervical vertebrae and was against the hide perfectly expanded. Bw my son and cousin we havent yet had a petal shear. So far on living animals, not counting penetration tests we have used em on deer, elk, black bear, cougar, lion, wildebeest, kudu, oryx, and waterbuffalo.