Although I don't have ballistics for it, I have been told that the 500 S&W is pretty well Maxed out in the longer pistol barrel and several guys who have the 22 Inch NEF Handi rifles report about the same velocities as the hand gun. However not many are experimenting with it in rifles yet as there are not many out there. You might try the NEF forum at www.graybeardoutdoors.com. Many of them have the 22 inch handi rifle which is a pretty good gun.