.460 Weatherby Magnum

Fourth from right

Type

Rifle

Place of origin

United States

Production history

Designer

Roy Weatherby

Designed

1957

Manufacturer

Weatherby Inc.

Produced

1959–present

Specifications

Parent case

.378 Weatherby Magnum

Case type

belted, bottlenecked

Bullet diameter

.458 in (11.6 mm)

Neck diameter

.481 in (12.2 mm)

Shoulder diameter

.560 in (14.2 mm)

Base diameter

.582 in (14.8 mm)

Rim diameter

.579 in (14.7 mm)

Rim thickness

.063 in (1.6 mm)

Case length

2.913 in (74.0 mm)

Overall length

3.65 in (93 mm)

Case capacity

141.1 gr H₂O (9.14 cm³)

Rifling twist

1 in 16 in (410 mm)

Primer type

Large rifle magnum

Maximum pressure

65,000 psi (450 MPa)

Ballistic performance

Bullet mass/type	Velocity	Energy
500 gr (32 g) FMJ	2,600 ft/s (790 m/s)	7,504 ft·lbf (10,174 J)
500 gr (32 g) Round Nose	2,600 ft/s (790 m/s)	7,504 ft·lbf (10,174 J)
450 gr (29 g) Truncated Solid	2,660 ft/s (810 m/s)	7,072 ft·lbf (9,588 J)

Test barrel length: 26 inches (660 mm)
Source(s): Weatherby

The .460 Weatherby Magnum is a belted, bottlenecked rifle cartridge, developed by Roy Weatherby in 1957. The cartridge is based on the .378 Weatherby Magnum necked up to accept the .458-inch (11.6 mm) bullet. The original .378 Weatherby Magnum parent case was inspired by the .416 Rigby. The .460 Weatherby Magnum was designed as an African dangerous game rifle cartridge for the hunting of heavy, thick skinned dangerous game.

The .460 Weatherby Magnum was the world's most powerful commercially available sporting cartridge for 29 years until the advent of the .700 Nitro Express by Holland & Holland, London, England, in 1988 developing approximately an average of 8,900 foot-pounds force (12,100 J) of muzzle energy with a 1,000 gr (65 g) bullet at 2,000 ft/s (610 m/s). However handloaders can push the cartridge to generate as much as 15,000 foot-pounds (20,000 J) of energy in a modern bolt action, by using a 1,000 gr (65 g) bullet fired at 2,600 ft/s (792 m/s). However, doing so necessitates a rifle so heavy it is almost inoperable for hunting purposes. The .700 Nitro Express was itself eclipsed in only five years by the 1993 introduction by A-Square of the .577 Tyrannosaur. The .577 T-Rex develops approximately 10,180 foot-pounds force (13,800 J) with a velocity of 2,460 ft/s (750 m/s).

The .460 will launch a 500-grain (32 g) bullet at a chronographed velocity of 2,700 ft/s (820 m/s) from a 26-inch (660 mm) barrel, measuring 8,100 ft·lbf (11,000 J) of muzzle energy. Prior to the arrival of the .460 Weatherby Magnum on the hunting scene, the .600 Nitro Express had been considered to be the most powerful cartridge in terms of energy.

Roy Weatherby had expected that the .378 Weatherby Magnum to make some headway in the African continent but believed that his cartridge was being bypassed for low velocity, big bore cartridges by professional hunters who he felt were resistant to change. Furthermore, new regulations prohibiting the hunting of heavy, thick skinned, dangerous game with sub-.40 caliber (10.16 mm) cartridges were being enacted in some African countries. These regulations would essentially ban the use of all previous Weatherby cartridges for the hunting of elephant, African Cape buffalo and rhinoceros.

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Wikipedia