The Beretta M9 pistol is a light, semiautomatic pistol with a weight of 2.1 pounds that uses a standard staggered box magazine with a capacity of 15 rounds. The two types of ammunition it uses are the M882 9-millimeter ball and M917 9-millimeter dummy, and holders of the M9 normally carry 45 rounds.
While the maximum range of the M9 is 1800 meters, its maximum effective range is only 50 meters. The main components of the M9 are the slide and barrel assembly, the recoil spring and recoil spring guide, the barrel and locking block assembly, the receiver, and the magazine. The M9 comes with redundant automatic safety settings that lower the chance of accidental firings. The three safety features found on the M9 are the use of decocking, the safety lever and the firing pin block. It can be operated in both single or double action mode, and it can be unloaded while the safety is in the "on" position. The M9 may be fired even if a magazine has not been loaded, and it can have the hammer change from the cocked to uncocked position by switching the thumb safety to the "on" position.
The M9 came about as a result of a Congressionally directed Non-Developmental Initiative. This program attempted to standardize the United States Department of Defense with NATO and provide all United States armed services with the same handgun.