The .276 Pedersen (7×51mm) round was an experimental 7 mm cartridge developed for the United States Army. It was used in the Pedersen rifle and early versions of what would become the M1 Garand. Comparable to the contemporary Italian 6.5×52mm (0.268 in) Carcano or the Japanese 6.5mm (0.264 in) Arisaka, it produced velocities of around 2,400 feet per second (730 m/s) with 140 or 150 grain (9.1 or 9.7 g) projectiles.
Service history
In service 1923–1932 (experimental)
Used by United States
Production history
Designer John Pedersen
Designed 1923
Specifications
Case type Rimless, bottleneck
Bullet diameter .2842 in (7.22 mm)
Neck diameter .313 in (8.0 mm)
Shoulder diameter .385 in (9.8 mm)
Base diameter .450 in (11.4 mm)
Rim diameter .450 in (11.4 mm)
Case length 2.023 in (51.4 mm)
Overall length 2.855 in (72.5 mm)
Primer type Large rifle