It is a cartridge for the .45 caliber automatic Colt pistol. It is the standard cartridge- the bulet weighs 230 grains, and is typically a round nosed full metal jacketed bullet.
Not sure where you got your information from. Define inaccurate. I've shot 45ACP 230 grain ammo out of a WWII M1911A1 that would put them all in the chest of an E series target at 25 yards. All weapons will exhibit a preference for one or more types of ammo/loads. You have to experiment.
No one. A standard .45 ACP bullet is about 230 grains. A .45 caliber bullet that only weighed 50 grains would merely be a very thin disk of lead.
No. 7.65x17SR is .32 ACP.
.45 ACP
32 acp.
If it's chambered for the .45 ACP cartridge, yes.
ACP stands for Automatic Colt Pistol. They are the same.
380 ACP, 9mm Kurz
No. 7.65x17SR is .32 ACP.
.380 ACP
There is no difference. ACP stands for Automatic Colt Pistol.
Any standard .380 ACP ammo, yes.