An acquaintance would like to purchase my pellet rifle. He is under 18 so I told him I would only sell it if he had someone over 18 with him. He said that his brother who is over 18 would come. As long as I sell the rifle to his older brother am I free of any liability after the sale? I have every reason to believe that the rifle will be used only for legal activities but I just want to make sure to cover my butt. Any advice?