5.56x45mm NATO

The 5.56x45mm NATO round is a 77-90 grain rifle cartridge.

Description
The 5.56x45mm round is cheap and reliable for medium to heavy combat. While it does not have high penetration power, it does considerable damage for its size.

Trivia

 * Guns that use 5.56x45mm rounds typically cycle faster than guns that use heavier bullets
 * 5.56x45mm is not particularly effective against heavy armor