.300 Weatherby Magnum

.300 Weatherby Magnum
.300 Weatherby cartridge
TypeRifle
Place of originUSA
Production history
DesignerRoy Weatherby
Designed1944
ManufacturerWeatherby
Produced1944–present
Specifications
Parent case.300 H&H Magnum
Case typeBelted, bottleneck
Bullet diameter.308 in (7.8 mm)
Neck diameter.336 in (8.5 mm)
Shoulder diameter.492 in (12.5 mm)
Base diameter.512 in (13.0 mm)
Rim diameter.531 in (13.5 mm)
Case length2.825 in (71.8 mm)
Overall length3.562 in (90.5 mm)
Rifling twist1-10
Primer typeLarge rifle magnum
Maximum pressure65,000 psi (450 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
150 gr (10 g) SP 3,540 ft/s (1,080 m/s) 4,173 ft⋅lbf (5,658 J)
165 gr (11 g) SP 3,390 ft/s (1,030 m/s) 4,210 ft⋅lbf (5,710 J)
180 gr (12 g) BST 3,250 ft/s (990 m/s) 4,223 ft⋅lbf (5,726 J)
200 gr (13 g) Partition 3,060 ft/s (930 m/s) 4,158 ft⋅lbf (5,637 J)
220 gr (14 g) Rn-Ex 2,845 ft/s (867 m/s) 3,954 ft⋅lbf (5,361 J)
Test barrel length: 26
Source(s): Weatherby [1]

The .300 Weatherby Magnum is a .30 caliber rifle cartridge created by Roy Weatherby in 1944 and produced by Weatherby. It has become the most popular of all the Weatherby cartridges.[1]