.257 Weatherby Magnum

1944 · Roy Weatherby · 2 firearms in catalog

Also known as: .257 Wby Mag, .257 Weatherby

Cartridge specifications

Bullet Diameter6.53 mm (0.257")
Neck Diameter7.21 mm (0.284")
Base Diameter13.03 mm (0.513")
Case Length64.77 mm (2.550")
Overall Length84.84 mm (3.340")
Max Pressure431 MPa (62,500 psi)
Typical Bullet Weight7.45 g (115 gr)
Typical Muzzle Velocity1036 m/s (3399 fps)
Typical Muzzle Energy4002 J (2952 ft·lbf)
Primer TypeLarge Rifle Magnum
Cartridge TypeBelted
Introduced1944

Firearms chambered in .257 Weatherby Magnum