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.
|Bullet diameter||.452 in (11.5 mm)||9.01 mm (0.355 in)|
|Neck diameter||.473 in (12.0 mm)||9.65 mm (0.380 in)|
|Base diameter||.476 in (12.1 mm)||9.93 mm (0.391 in)|
|Case type||Rimless, straight||Rimless, tapered|
|Rim diameter||.480 in (12.2 mm)||9.96 mm (0.392 in)|
|Case length||.898 in (22.8 mm)||19.15 mm (0.754 in)|
|Place of origin||United States||German Empire|
|Overall length||1.275 in (32.4 mm)||29.69 mm (1.169 in)|
|Designer||John Browning||Georg Luger|
|Velocity||700 - 1150 FPS||950-1400 FPS|
|Maximum pressure||21,000 psi (140 MPa)||235.00 MPa (34,084 psi)|
|Cost||More expensive than .40 S&W and 9mm||Cheaper than .40 S&W & .45 ACP|
|Used by||United States and others||NATO and others; Militaries, police, and self defense.|
|Penetration||11.3-27”||8 - 40" (13')|
|Rim thickness||.049 in (1.2 mm)||0.90 mm (0.035 in)|
|Case capacity||25 gr H2O (1.625 cm³)||0.862 cm³ (13 gr H2O)|
|Primer type||primarily large pistol (but also small pistol in some brass)||Berdan or Boxer small pistol|
|Variants||.45 ACP +P, .45 Auto Rim, .45 Super||9 mm NATO, 9×19mm Parabellum +P, 9×19mm 7N21 +P+, 9×19mm 7N31 +P+|
|Felt Recoil||Heavier and pushes one's hands backwards instead of up. Does not have much muzzle flip.||Less recoil.|
|Type||Pistol / Revolver / Carbine / SMG / Derringer||Pistol / Revolver / Carbine / SMG / Derringer; Cartridge|
|Magazine Capacity (as shipped from factory)||6-14||6 to 20|
|Wars||World War I – present||World War I–present|
|Muzzle Energy||369 lb/ft (230gr at 850FPS)||304 lb/ft (124gr at 1050FPS)|
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”.
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.
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.
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.