.500 A-Square

.500 A-Square
TypeCenterfire/Rifle
Place of originUnited States
Production history
DesignerArthur Alphin
Designed1976
ManufacturerA-Square Company LLC
Produced1978–2011
Specifications
Parent case.460 Weatherby Magnum
Case typeBelted, bottleneck
Bullet diameter.510 in (13.0 mm)
Neck diameter.536 in (13.6 mm)
Shoulder diameter.568 in (14.4 mm)
Base diameter.582 in (14.8 mm)
Rim diameter.603 in (15.3 mm)
Rim thickness.059 in (1.5 mm)
Case length2.900 in (73.7 mm)
Overall length3.74 in (95 mm)
Case capacity141.45 gr H2O (9.166 cm3)
Rifling twist1 in 10"
Primer typeLarge rifle magnum
Maximum pressure63,860 psi (440.3 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
600 gr (39 g) Monolithic Solid 2,470 ft/s (750 m/s) 8,127 ft⋅lbf (11,019 J)
600 gr (39 g) Round Nose 2,470 ft/s (750 m/s) 8,127 ft⋅lbf (11,019 J)
Test barrel length: 26 inches (660 mm)
Source(s): http://www.midwayusa.com/viewProduct/?productNumber=551454 and [1]

The .500 A-Square is a belted, bottleneck rifle cartridge, developed by Arthur Alphin in 1976. The cartridge is based on the .460 Weatherby Magnum necked up to accept the .510 in (13.0 mm) bullet; the same as the .50 BMG cartridge. This was Col. Alphin's first commercial sporting cartridge and was designed in “response to some severe problems experienced with the .458 Winchester on safari in Mozambique.”[1]

The .500 A-Square was a proprietary cartridge and the world's most powerful commercially available “sporting” cartridge. However, the .50 BMG is the world's most powerful commercial cartridge for any shooting purpose. The .500 A-Square is used specifically as an African, thick skin, dangerous game, rifle cartridge for the hunting of elephants and Cape buffalo as well as a backup gun for professional hunters and guides.

  1. ^ a b Alphin, Col. Arthur B. (1996) [1996]. Alphin, Col. Arthur B. (ed.). Any Shot You Want (1st ed.). On Target Press. p. 605. ISBN 0-9643683-1-5.