.223 Rem Frangible

Totally ok for shooting out of a rifle chambered in either .223 Rem or 5.56. the .223 frangible is specifically designed to fall apart on impact with a hard service. These are excellent for close-range steel targets. shoot-houses and CQB training. The projectile is made of compressed metals. making them more fragile than an FMJ. 

Note that despite their more fragile  projectile. these are extremely lethal. 

Brass: New or Reman

*IMPORTANT: Though both cartridges look identical. 5.56 is loaded to a higher pressure than .223. which is why rifles chambered for a 5.56 cartridge can fire .223. but it is not recommended that 5.56 cartridges are fired out of a rifle chambered for .223

Not sure what the abbreviations are?