Winchester Rifle Brass .223 Remington Unprimed 100/Pack. During manufacturing cases go through annealing to produce the correct hardness that holds the bullet securely in place but also provides flexibility when firing. Because of this the cases may have a light stain near the neck.Sometimes the cases arrive with imperfect mouths due to manufacturing or shipping. For reloading the mouth needs to be resized as well as chamfered and deburred. If wanted an expander ball can be pushed through the neck in line with the sizing die. Specifications for Winchester .223 Remington Unprimed Rifle Brass: Manufacturer: Winchester Caliber: .223 Remington Primed: No Brass Quantity: 100 Piece Cartridge Case Material: Brass Package Contents: Winchester .223 Remington Unprimed Rifle Brass Winchester WSC223RU: Rifle Brass .223 Remington Unprimed 100/Pack