There is no one answer- because there is no one gunpowder, and no one bullet weight. Amount of powder is driven mainly by those two factors. If you intend to reload, get a copy of ABCs of Reloading, and read entire book first- excellent reference.
Technically speaking- none. A bullet is the solid metal part of a cartridge that is fired out of the barrel. How much gunpowder is in a 9mm Parabellum CARTRIDGE will depend on the powder used and the bullet weight. I reload with 4.6 grains of Bullseye powder with a 115 gr bullet, but there are dozens of other loads.
Different makers. The cartridge used is the 9x19.
A single 9mm bullet is about 3-6 cents. A 9mm Parabellum (Luger) CARTRIDGE is about .30-.55.
The 9mm Parabellum cartridge made by the Reminton-Peters cartridge company.
Depends. .380 ACP is used to refer to the 9x17 cartridge. It is not interchangeable for use in 9x18 (9mm Makarov), 9x19 (9mm Parabellum/Luger), or any other firearm designed for any cartridge other than the .380 ACP/9x17 cartridge.
A pistol chambered for .380 ACP (also known as 9x17) can fire that cartridge and only that cartridge. You cannot shoot 9mm Parabellum (9x19) or any other 9mm cartridge in it.
9mm and 380 both use bullets with a diameter of .355. But the answer to the question you're probably asking is, no, you cannot fire a 9mm parabellum cartridge from a .380 handgun. The 9mm cartridge is different than the .380 cartridge. Even though both are 9mm in diameter, the overall cartridge lengths are different.
Depends on the loading of the cartridge, and the gun it is shot from, but the 9mm Parabellum (9mm Luger) cartridge travels between 1200 and 1400 feet per second on the average.
No. While there are several different 9mm cartridges, none of them interchange with a 7.62 cartridge. You need to clarify your question- there is no such cartridge as a 7.62 9mm. There are 7.62 pistols, but 9mm is a caliber, not a type of firearm.
9mm Short is another term for the .380 ACP cartridge.
The .357 Magnum is a larger cartridge, can fire a heavier bullet, and has about twice the energy of a 9mm Parabellum cartridge.
It depends on what you mean exactly. 380 is a bullet that is 9mm in diameter, but it is not the same as what most people mean when they say 9mm. Usually, at least in the U.S. the term 9mm refers to 9mm para which is 9x19. A 380 cartridge is 9x17, so it is shorter. It may be possible to fire a 9x19 cartridge out of a 380 gun, but it is a bad idea because it is too long, and because it is a much higher pressure cartridge.