Article makes it sound like a new development.
Not:
https://www.athlonoutdoors.com/article/big-horn-armory-ar500-auto-max-review/
“...The .500 Auto Max’s heavy, large-diameter bullets make it well-suited for use against engine block... the same can be said for assailants with body armor... It passes through automotive body panels as easy as a deer cavity...”
Hmmmm...