Yes, a Ruger Alaskan in .454 Casull with 300-grain bullets can potentially kill an African elephant, but it requires precise shot placement and is not a recommended or legal option in most regions. The .454 Casull is a powerful handgun cartridge, capable of delivering significant energy, with a 300-grain bullet traveling at around 1,650 feet per second and generating approximately 1,813 foot-pounds of energy at the muzzle.