.44 Magnum Overview The  .44 Remington Magnum , also known as  .44 Magnum  or  10.9x33mmR is a rimmed, large-bore cartridge originally designed for revolvers and quickly adopted for carbines and rifles. Famously called "the most powerful handgun [cartridge] in the world" by Clint Eastwood in  Dirty Harry , the .44 Magnum has since been eclipsed in power by the .454 Casull , .480 Caning Magnum  and .500 S&W Magnum; nevertheless, due in part to its more manageable recoil, it has remained one of the most popular commercial large-bore magnum cartridges Stats Note: 343.2 m/s is the subsonic barrier - anything below that is considered subsonic. Subsonic ammunition removes the bullet crack down range making the round better suited to stealth. Ammunition Type Damage Bullet Velocity (m/s) Barrier Penetration 180GR XTP 24.74 503 1.81 225GR XPB 26.4 376 4.3 300GR XTP 31.5 380 1.6 Paralight AP 15.2 689 14.5 Pyrotechnic 11.5 + 3@0.5m 380 0.2 Note: Barrier penetration represents the rounds ability to go through walls and barriers. Armor piercing represents the rounds ability to penetrate body armor plates.