British rook rifle cartridge — .297 case necked to accept a .250 bullet. A higher-velocity variant of the rook rifle family, used for pest control at modest ranges.
Type: Rifle
Introduced: 1880, United Kingdom
Parent case: None
Standardization: Obsolete / Non-standard
Bullet diameter: 0.25" (6.35 mm)
Max pressure: 18,000 PSI
Rim type: Rimmed
Primer: Large Rifle
Typical twist rate: 1:14
Muzzle velocity: 1000–1100 fps
Muzzle energy: 111–161 ft-lbs
Effective range: 200 yd
Common bullet weights: 50, 60 gr
Primary use: hunting
Production status: Obsolete
Also known as: 297/250 Rook · .297-250 Rook · .297/250
History: Another British rook rifle cartridge, featuring a larger case than the .255 Rook while maintaining similar ballistics. Used in the classic British rook rifles for estate vermin control. The tradition of rook shooting with specialized rifles died out as rimfire cartridges became practical for the same purpose.