6×45mm

Photo coming soon: side view on a transparent background, with author and license.

Key specs

Type: Rifle
Origin: United States
Introduced: 1965
Case type: rimless, bottleneck
Bullet diameter: 6.20 mm
Case length: 44.70 mm
Typical bullet: 70 gr
Typical velocity: 914 m/s
Typical energy: 1,898 J
Parent case: .223 Remington

Sources

Wikipedia: 6×45mm, Wikipedia