From Guns.com:

Kuntz said “this is the most powerful, widely available AR on the market today … out of this 18 inch barrel we’re able to put a 440 grain hard cast downrange at 2,200 feet per second, resulting in 4,500 foot pounds of energy.” He added the 500 Auto Max, which has the same load data, shelf life and power as a .500 S&W.