Red Army Standard 5.45x39mm Ammo 59 Grain FMJ Steel Case ammo review offers the following information: Introducing Century Arms Red Army Standard ammunition. This new 5.45x39 ammunition features a 59 grain lead core full metal jacket boat tail. Sealed pimers and case necks add to the value of this non-corrisive steel cased ammo. Although case length is the same 39mm, the 5.45X39 is not based on the7.62X39mm case; with a smaller base diameter and a .220-inch bullet it is much more similar to the 5.56x45mm NATO cartridge, but with a shorter and slightly fatter case.