10mm Auto 

A powerful semi-automatic pistol cartridge introduced in 1984 for the unsuccessful Bren Ten. The cartridge is today quite underrated and rather uncommon, but is used for handgun hunting and self-defense.
A less powerful version of the cartridge was later developed for the FBI; this became known as the now very popular .40 S&W.
Guns chambered for this cartridge include:
Bren Ten, Glock G20, Colt Delta Elite, MP5/10 submachinegun

My uncle just nailed a white-tail deer with his Glock 20 with a 10mm Auto FMJ.

10mm Auto by Zolotros June 25, 2009

10mm Auto 

A pistol cartridge developed orginally for law enforcement, intended as a mid-way cartridge between the 9mm and .45 ACP. It's ballistics are similar to those of the .41 Magnum.

The FBI adopted Smith & Wesson's Model 1076 10mm pistol.

10mm Auto by JoeBob August 30, 2003