The story of the 9mm vs .45 ACP is kind of a strange one. If you asked even self-described “gun people,” they would likely say that the 9mm is the newer cartridge, and the .45 ACP (or .45 Auto) is an ...

Key point: The first of the 9mm handguns that continue to dominate the handgun market. One of the longest-serving handguns of all time was the final work of the most prolific gun designer of all time.

A wider variety of 9mm pistols (left) is available, but the 10mm pistols (right) are part of a fast-growing category. The 9mm and 10mm are cartridges with only a millimeter of difference in bullet ...