Just for grins, yesterday I took a pair of Cabela's shooting glasses that were too scratched to wear, mounted em in a cardboard box, measured off 15 yards per the original question. "H" grade Lefever choked per Mr. Joe Wood, cylinder bore-shot straight on into the glasses. Both lenses shattered....If I hadnt lost the capability, I'd post pictures, didnt take any...eyes, ears and nose woulda been gone...