44 Magnum has since been eclipsed in power by the. 44 Special case but lengthened and loaded to higher pressures for greater velocity and energy.įamously called 'the most powerful handgun in the world' by Clint Eastwood in Dirty Harry, the. Despite the '.44' designation, guns chambered for the. 44 Magnum or 10.9x33mmR, is a rimmed, large-bore cartridge originally designed for revolvers and quickly adopted for carbines and rifles.