.60 caliber (15.2×114mm)

.60

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

Key specs

Type: Rifle
Origin: United States
Introduced: 1939
Case type: rimless, bottleneck
Bullet diameter: 15.24 mm
Overall length: 113.79 mm
Parent case: .50 BMG

Sources

Wikipedia: .60 caliber, Wikipedia