9mm and 380 both use bullets with a diameter of .355. However, the cases are a different size. .380 is also known as .380 auto, 9mm Kurtz, 9mm Corto, 9mm short or 9x17. 9mm typically refers to 9x19mm also known as 9mm Parabellum or 9mm Luger. You cannot fire a 9mm Parabellum cartridge from a .380 handgun. The 9mm cartridge will not fit into the chamber of the gun. However, if you were to pull the bullet out of the .380 case and put it into a 9mm Para case the resulting cartridge will work just fine.
380 ACP or 9mm short or 9mm corto
.380 ACP, also known as 9x17mm, 9mm Short, and 9mm Kurz.
.380 ACP means .380 Caliber, Automatic Colt Pistol. Often shortened to 380 auto. In other parts of the world, the 380 ACP is called a "9mm short" (or Kurtz, Corto other languages for "short."). So yes.
9mm (usually called 9mm Luger or 9mm Parabellum) almost always has a higher muzzle velocity than the 380 ACP (also called the 9mm short, 9mm Kurtz, and 9mm Corto). The two bullets are essentially the same diameter however the 9mm Parabellum is almost always a heavier bullet than the 380 ACP with a larger powder charge and a significantly higher chamber pressure.
380 and 9mm ammunition IS NOT INTERCHANGEABLE.
380 and 9mm ammunition IS NOT INTERCHANGEABLE.
The .380 IS a 9mm- a 9mm Short (also called 9mm Kurz or Corto). There are more than a dozen different 9mm cartridges. Most people mean the 9mm Parabellum (also called 9mm Luger) when they say 9mm. The 9mm Parabellum IS a longer cartridge than the .380 .
Assuming you're referring to the 9x19mm (also known as the 9mm Parabellum or 9mm Luger) and the .380 ACP (also known as the 9x17mm, 9mm Short, and 9mm Kurz), the answer is no on both counts, and it would be extremely dangerous to try this.
380 and 9mm projectiles are .355 in diameter _________________________ Most of the time, when people use the term 9mm, they are referring to a 9mm parabellum. A 9mm parabellum cannot be fired from a .380. The 9mm cartridge is longer. _________________________ The BULLET is the part of the cartridge that is the projectile. While 9mm parabellum and .380 ACP use the same diameter bullets, the CARTRIDGES are not interchangeable.
You cannot re-size 380 brass with a 9mm sizing die, nor can you size 9mm brass with a 380 die. You can use the the bullet seating dies back and forth. But you'll need to get sizing dies in both 380 and 9mm. The shell holder and primers are the same for both.
9mm and .380 bullets are the same diameter. In fact, .380 is also called 9mm Kurz(short) or 9x17. However, the caliber commonly called 9mm is 9x19, which means the cases are different size. A .380 cartridge will fall down into the chamber and the firing pin will not reach the primer. So, a .380 bullet can be fired from a 9mm gun if it were loaded into a 9mm case. A .380 cartridge would fail to fire in a 9mm gun.