378 Weatherby Magnum
Rifle Cartridge

Abbreviated Name:  378 Wby Mag

 
 

TECHNICAL INFORMATION:

Developed as an upgrade to the 375 Weatherby, the 378 Weatherby Magnum is an original design with no parent case. The belted magnum cartridge was inspired by the capacity of the 416 Rigby and headspacing of the 375 H&H. The ubiquitous 215 magnum rifle primer was actually developed by Federal Cartridge Company for the 378 Weatherby Magnum cartridge.

As with most Weatherby Magnums, there are a few points to keep in mind when loading for this cartridge:

  • The chambers have “freebore”, meaning they have a longer throat.
  • For best accuracy, bullets should be seated as long as the magazine will allow.
  • We recommend three shot groups when working up loads.
 

 

NOSLER AMMUNITION

Loaded for 378 Weatherby Magnum

Not offered at this time

 

 

NOSLER RIFLES

Chambered for 378 Weatherby Magnum

Not offered at this time

 

 

378 Weatherby Magnum
Loading & Reloading Components:

378 WBY MAG LOAD DATA

 

 

NOSLER BULLETS 

Designed for Loading & Reloading 378 Weatherby Magnum

 
 

AccuBond Bullet

  • 375 Caliber 260 Grain
  • 375 Caliber 300 Grain
 

Partition Bullet

  • 375 Caliber 260 Grain
  • 375 Caliber 300 Grain
 

Solid Bullet

  • 375 Caliber 260 Grain
  • 375 Caliber 300 Grain
 

 

NOSLER BRASS

Designed for Loading & Reloading 378 Weatherby Magnum

Not offered at this time

 

 

Available Cartridge Information:

 

RIFLE CARTRIDGES

 

35 Caliber / .358” Diameter

9.3mm Caliber / .366” Diameter

375 Caliber / .375” Diameter

416 Caliber / .416” Diameter

44 Caliber / .429” Diameter

45 Caliber / .458” Diameter

458 Caliber / .458” Diameter

 

 

HANDGUN CARTRIDGES

 

9mm Caliber / .355” Diameter

38 Caliber / .357” Diameter

10MM Caliber / .400” Diameter

41 Caliber / .410” Diameter

44 Caliber / .429” Diameter

45 Caliber / .451” Diameter