The 9mm or 9×19mm Parabellum is a firearms cartridge that was designed by Georg Luger and introduced in 1902 by the German weapons manufacturer Deutsche Waffen und Munitionsfabriken (DWM) (German Weapons and Munitions Factory) for their Luger semi-automatic pistol.
For this reason, it is designated as the 9mm Luger by the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI), and the 9mm Luger by the Commission Internationale Permanente pour l’Epreuve des Armes à Feu Portatives (CIP). The name Parabellum is derived from the Latin: Si vis pacem, para bellum (“If you seek peace, prepare for war”), which was the motto of DWM.
Under STANAG 4090, it is a standard cartridge for NATO forces as well as many non-NATO countries.
According to the 2014 edition of Cartridges of the World, the 9×19mm Parabellum is “the world’s most popular and widely used military handgun and submachinegun cartridge.” In addition to being used by over 60% of police in the U.S., Newsweek credits 9×19mm Parabellum pistol sales with making semiautomatic pistols more popular than revolvers. The popularity of this cartridge can be attributed to the widely held conviction that it is effective in police and self-defense use. Its low cost and wide availability contribute to the caliber’s continuing popularity.
The round was originally designed to be lethal to 50 meters, but is still lethal at longer ranges. The 9mm cartridge combines a flat trajectory with moderate recoil. According to the 1986 book Handloading: “the modern science of wound ballistics has established beyond reasonable doubt that the 9mm cartridge is highly effective.”
In 2014, the United States Federal Bureau of Investigation (FBI) released a report detailing the potential combat effectiveness of the 9mm cartridge when compared to other calibers such as the .45 ACP and the .40 S&W cartridge that was specifically developed for use by the FBI. The report indicated that the new powders and more advanced bullet designs used in current 9mm defensive loads allowed for the caliber to deliver almost similar performance to other calibers, like the .45 ACP, and .40 S&W. In addition to this, the lower recoil, less wear, cheaper ammunition and higher capacity were all reasons that the report cited for the recent surge in orders of the ammunition from various police agencies. With a wider selection of officers being able to shoot handguns chambered in 9×19mm, many departments choose this caliber so they can standardize around a single firearm and loading, making logistics and supply easier. Due to all of these factors, law enforcement orders of 9mm ammo from all major ammunition manufacturers have spiked significantly.
The FBI report made it clear that the more consistent accuracy of 9mm in the hands of their less experienced shooters was a factor in their returning to 9mm as their standard handgun caliber. It was also made clear that the almost same effectiveness of 9mm compared to .40 S&W and .45 ACP was due to the high quality of 9mm ammunition available.