If you want to know what it will do just go to Freed`s web page and look at the data he has on the .19 Calhoon, it will be almost identical. I shoot the .17 Ackley Hornet. I push a 19 gr. bullet at 3,500 fps. with H-4227. I could probibly get more velocity with Lil`Gun but it shooting in the 2`s and so I never tried and other powder.