A round is the projectile that comes out of the gun. You actually load into... That is right, isn't it? Let me just make sure. So bullets are the things that fly out of the end of the gun and that will kill or seriously injure someone, right? That's a bullet. Okay, so that is also known as a cartridge. I want round, cartridge, a difference. Come on, come on, internet. The words are used interchangeably, especially regarding metal case ammunition. That's a cartridge and a round.