Type Rifle Parent case .223 Remington Neck diameter .203 in (5.2 mm) | Place of origin United States Bullet diameter .172 in (4.4 mm) Shoulder diameter .358 in (9.1 mm) | |
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The .17-223 is a centerfire wildcat rifle cartridge. It is based on the .223 Remington, but the neck is re-sized to accept a .17 caliber bullet.
References
.17-223 Wikipedia(Text) CC BY-SA