A 9mm is generally cheaper, has less recoil and higher velocity than a .45 ACP. The .45 ACP (Automatic Colt Pistol) cartridge holds bullets that have a diameter of .452 inches (11.5mm) so it is slightly larger than the 9mm (.355 inch bullets). Both cartridges have a long history and were first designed over 100 years ago.
Contents: .45 ACP vs 9mm
The 9mm has a bullet diameter of 9.01mm (0.355 in), a neck diameter of 9.65mm, a base diameter of 9.93 mm, a rim diameter of 9.96mm and a rim thickness of 0.90 mm.
The .45 has a bullet diameter of 11.5 mm (.452 in), a neck diameter of 12.0mm, a base diameter of 12.1 mm, and a rim diameter of 12.2 mm.
A 9mm averages between 8” and 15.9” penetration. However, the Winchester FMJ has a penetration of 24.5” and the Doubletap JFN+P trail defense has a penetration of 40”. The cartridge expands to approximately 0.35 to 0.72”.
A .45 averages about 11.3”-14.3” penetration. However, the Remington FMJ has 27” penetration. The cartridge expands to an average of 0.75” inches, but the Remington FMJ expands to 0.45”.
edit Magazine capacity
Due to the smaller size of the round, 9mm guns typically have a higher magazine capacity than a .45, although the specifics vary depending on the type of gun. For example, the Glock 17 holds a standard 17 rounds of 9mm, while the Glock 21 holds a standard 13 rounds of .45.
A 9mm has less recoil than a .45.
A 9mm fires bullets with a velocity of between 990 and 1350 feet per second.
A .45 fires bullets with an average velocity between 835 and 1150 feet per second.
A 9mm gun costs between 40% and 50% less than a .45.
edit Production History
The 9mm cartridge was designed by Georg Luger in 1901. It has been produced since 1902.
The .45 was developed by John Browning in 1904. It has been used by the United States and other militaries since World War I.
edit Evolution and Usage
The 9mm cartridge was developed from Luger’s 7.65x21mm Parabellum. The bottleneck of that cartridge was removed, leaving a tapered, rimless cartridge. It was adopted by the German Navy in 1904 and the German Army in 1906. It became more popular after World War I and has since become the most common caliber for U.S. law enforcement agencies and for military and law enforcement agencies around the world. It is also popular for self-defense.
The .45 was developed by the U.S Cavalry in the late 1890s and early 20th century in a bid to create a bullet that was more effective against determined opponents. It was intended to be a “real man-stopper.” It was adopted by the United States Army in 1911.
".45 ACP vs 9mm." Diffen.com. Diffen LLC, n.d. Web. 24 Jul 2014. < http://www.diffen.com/difference/.45_ACP_vs_9mm >