Black Powder Express cartridge in the .450/400 family, 2 3/8 inch case. Distinct from the later 3 inch Nitro Express version. Used in double and single-shot rifles for medium to large game in the black powder era.
Type: Rifle
Introduced: 1880, United Kingdom
Parent case: None
Standardization: Obsolete / Non-standard
Bullet diameter: 0.408" (10.36 mm)
Max pressure: 18,000 PSI
Rim type: Rimmed
Primer: Large Rifle
Typical twist rate: 1:16
Muzzle velocity: 1600–1800 fps
Muzzle energy: 1534–1943 ft-lbs
Effective range: 150 yd
Common bullet weights: 270 gr
Primary use: hunting
Production status: Obsolete
Also known as: .450/400 Black Powder Express 2 3/8" · 450/400 BPE 2 3/8" · .450/400 BPE
History: One of the earliest Nitro Express cartridges, developed in the 1890s as the transition from black powder to smokeless powder occurred in British sporting rifles. The 2 3/8" case was designed for older double rifles being converted to use the new nitro propellants. Preceded by black powder equivalents.