Firearm nomenclature is probably the most messed up nomenclature around. Some said they didn't know if 1911's were 9mm I understand there the confusion can come in. The .38 acp and the higher pressure .38 super are both 9mm. The short .380 is also a 9mm. The .38 special revolver and the .357 magnum revolver cartridge is a 9mm. 35 Remington, .356 Winchester, .358 Winchester, .35 Whelen, .350 Remington Magnum and .358 Norma Magnum are all rifle cartridges and are also 9mm. When people say 9mm today they are usually referring to the 9x19 also known as 9mm nato, 9mm Luger, 9mm Parabellum. In addition there is the 9x23 (one of my favorites) 9x25, 9mm largo, 9mm Bergmann-Baynard, and the .357 Sig. Several of these cartridges can easily work in a 1911 but the only ones to me that makes sense to me are the 23mm cased ones.