It's a new cartridge. They necked down the .22 Hornet to .17 caliber. Wondering if H&R are going to do make a gun for it. While it is not as fast as the .17 Remington, or the .17 Fireball, I believe it is doing over 3700fps. (I'll have to check on that but I think I am right). Great trajectory out to 300 yards.