.223 Remington

From left: .222 Remington, 223 Remington, and 5.56×45mm NATO

The .223 Remington (.223 Rem) is a type of firearm cartridge. It is the most used cartridge for AR-15 type rifles.

.223 Remington Media

.223 Remington maximum C.I.P. cartridge dimensions. All sizes in millimeters (mm).
(Left to right) .223 Rem, .243 Win, .308 Win

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