.475 A&M Magnum
Encyclopedia
The .475 A&M Magnum is a rifle
cartridge
developed in the United States
. At the time of its development it was considered the most powerful sporting rifle cartridge ever developed. However, as the .475 A&M Magnum was a wildcat
cartridge, the .460 Weatherby Magnum
continued to be the most powerful commercial sporting cartridge available.
The cartridge and rifle were designed by the Atkinson & Marquart Rifle Co. of Prescott
, Arizona
, by necking up the then new .460 Weatherby Magnum
to accept a 0.475 in (12.1 mm) diameter bullet. Fred N. Barnes, the founder of Barnes Bullets for whom the first rifle chambered for this cartridge was made, supplied the bullets. According to anecdotes, Fred Barnes has gathered a group of people to demonstrate the rifle. The rifle was fired at the base of a small tree which was uprooted while Fred Barnes who had been shooting from a crouched position on a gravel bed had slid a few feet and ended on his back due to the recoil.
The .475 A&M Magnum was never available commercially, and was only Barnes Bullets and Custom Brass and Bullets provided bullet for the cartridge. Only a small number of rifles have been chambered for this cartridge. Brass is easily fireformed using .460 Weatherby Magnum brass. Dies are available from Custom Brass and Bullets.
Rifle
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves cut into the barrel walls. The raised areas of the rifling are called "lands," which make contact with the projectile , imparting spin around an axis corresponding to the...
cartridge
Cartridge (firearms)
A cartridge, also called a round, packages the bullet, gunpowder and primer into a single metallic case precisely made to fit the firing chamber of a firearm. The primer is a small charge of impact-sensitive chemical that may be located at the center of the case head or at its rim . Electrically...
developed in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. At the time of its development it was considered the most powerful sporting rifle cartridge ever developed. However, as the .475 A&M Magnum was a wildcat
Wildcat cartridge
A wildcat cartridge, or wildcat, is a custom cartridge for which ammunition and firearms are not mass produced. These cartridges are often created in order to optimize a certain performance characteristic of an existing commercial cartridge.Developing and using wildcat cartridges does not...
cartridge, the .460 Weatherby Magnum
.460 Weatherby Magnum
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 bullet. The original .378 Weatherby Magnum parent case was inspired by the .416 Rigby...
continued to be the most powerful commercial sporting cartridge available.
The cartridge and rifle were designed by the Atkinson & Marquart Rifle Co. of Prescott
Prescott, Arizona
Prescott is a city in Yavapai County, Arizona, USA. It was designated "Arizona's Christmas City" by Arizona Governor Rose Mofford in the late 1980s....
, Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
, by necking up the then new .460 Weatherby Magnum
.460 Weatherby Magnum
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 bullet. The original .378 Weatherby Magnum parent case was inspired by the .416 Rigby...
to accept a 0.475 in (12.1 mm) diameter bullet. Fred N. Barnes, the founder of Barnes Bullets for whom the first rifle chambered for this cartridge was made, supplied the bullets. According to anecdotes, Fred Barnes has gathered a group of people to demonstrate the rifle. The rifle was fired at the base of a small tree which was uprooted while Fred Barnes who had been shooting from a crouched position on a gravel bed had slid a few feet and ended on his back due to the recoil.
The .475 A&M Magnum was never available commercially, and was only Barnes Bullets and Custom Brass and Bullets provided bullet for the cartridge. Only a small number of rifles have been chambered for this cartridge. Brass is easily fireformed using .460 Weatherby Magnum brass. Dies are available from Custom Brass and Bullets.
Sources
- Barnes, Frank C., ed. by John T. Amber. ".475 A&M Magnum", in Cartridges of the World, pp. 142–3. Northfield, IL: DBI Books, 1972. ISBN 0-695-80326-3.