The most powerful .338 in a standard-length action for decades. Outperforms .338 Win Mag by 200-300 fps while fitting in a standard Weatherby Mark V.
Type: Rifle
Introduced: 1962, United States
Parent case: .375 H&H Magnum
Standardization: SAAMI
Bullet diameter: 0.338" (8.59 mm)
Case length: 2.825" (71.76 mm)
Overall length: 3.6" (91.44 mm)
Max pressure: 63,800 PSI
Rim type: Belted
Primer: Large Rifle Magnum
Typical twist rate: 1:10
Muzzle velocity: 2700–3200 fps
Muzzle energy: 3237–5115 ft-lbs
Effective range: 600 yd
Common bullet weights: 200, 225, 250, 275 gr
Primary use: Big Game, Dangerous Game, Hunting
Production status: Active
Also known as: .340 Wby Mag
History: Introduced in 1962 for hunters who wanted more than .338 Win Mag but didn't need the extreme dimensions of African express cartridges. Found success with Alaskan guides and hunters pursuing large bears and moose at extended ranges.
Notable firearms: Weatherby Mark V
Similar cartridges: .338 Winchester Magnum, .338 Lapua Magnum, .300 Weatherby Magnum