Winchester Short Magnum
Encyclopedia
Winchester Short Magnum, or WSM, refers to a family of rebated rim
bottlenecked centerfire short magnum
cartridge
s developed in the early 2000s by the U.S. Repeating Arms Company
, the maker of Winchester rifle
s and one of the oldest firearms manufacturers in the United States. All of the WSM cartridges are based on the .404 Jeffery
non-belted magnum cartridge which is shortened to fit a short rifle
action (such as a .308 Winchester
).
U.S. Repeating Arms Company used the same concept and the same base case in creating its even shorter Winchester Super Short Magnum
cartridges, three of which were introduced in 2003 and 2004.
Patriot, was designed to operate in a short-action rifle, instead of requiring a long action. The U.S. Repeating Arms Company was the first major manufacturer to commercialize Lazzeroni's concept, followed shortly thereafter by Remington
with their "Short Action Ultra Mag" line.
The WSM family of cartridges are Delta L problem
cartridges, meaning they can present unexpected chambering and/or feeding problems. The Delta L problem
article explains this problem in more detail.
and African plains game, the .325 WSM being an excellent cartridge for elk, bison and similar big game.
The cartridges in this family are, in order of development:
Rim (firearms)
A rim is an external flange that is machined, cast, molded, stamped or pressed around the bottom of a firearms cartridge. The rim may serve a number of purposes, the most common being as the place for the extractor to engage...
bottlenecked centerfire short magnum
Magnum
Magnum may refer to several things:* Moses Magnum, a Marvel Comics villain*Magnum, P.I., a television series** Thomas Magnum, the lead character...
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...
s developed in the early 2000s by the U.S. Repeating Arms Company
U.S. Repeating Arms Company
The U.S. Repeating Arms Company. Inc. is the current business name of the Winchester Repeating Arms Company, famous for making Winchester rifles....
, the maker of Winchester rifle
Winchester rifle
In common usage, Winchester rifle usually means any of the lever-action rifles manufactured by the Winchester Repeating Arms Company, though the company has also manufactured many rifles of other action types...
s and one of the oldest firearms manufacturers in the United States. All of the WSM cartridges are based on the .404 Jeffery
.404 Jeffery
The .404 Jeffery is a large caliber, rimless cartridge designed for large, dangerous game, such as the big five of Africa. Other names for this cartridge include .404 Jeffery Rimless, .404 Rimless Nitro Express, and 10.75 × 73 mm...
non-belted magnum cartridge which is shortened to fit a short rifle
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...
action (such as a .308 Winchester
.308 Winchester
The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...
).
U.S. Repeating Arms Company used the same concept and the same base case in creating its even shorter Winchester Super Short Magnum
Winchester Super Short Magnum
Winchester Super Short Magnum, or WSSM is a line of rebated rim bottlenecked centerfire short magnum cartridges introduced by the U.S. Repeating Arms Company...
cartridges, three of which were introduced in 2003 and 2004.
7.82 Lazzeroni Patriot
The WSM family was inspired partially by a family of proprietary short magnum cartridges developed in late 1997, by John Lazzeroni, derived from a previous line of magnum cartridges he had created. The first Lazzeroni short magnum, the 7.82 LazzeroniLazzeroni cartridge
Lazzeroni cartridges are a range of extremely powerful proprietary magnum sporting rifle cartridges developed and manufactured since the early 1990s by US hunting enthusiast John Lazzeroni...
Patriot, was designed to operate in a short-action rifle, instead of requiring a long action. The U.S. Repeating Arms Company was the first major manufacturer to commercialize Lazzeroni's concept, followed shortly thereafter by Remington
Remington Arms
Remington Arms Company, Inc. was founded in 1816 by Eliphalet Remington in Ilion, New York, as E. Remington and Sons. It is the oldest company in the United States which still makes its original product, and is the oldest continuously operating manufacturer in North America. It is the only U.S....
with their "Short Action Ultra Mag" line.
6 mm Benchrest
Another influence was a series of 6 mm cartridges developed for bench-rest target shooting competitions in the 1970s. The idea behind these cartridges was that a short, fat cartridge would be more "efficient" than the traditional long, narrow cartridge, as more of the powder column would be in the immediate vicinity of the primer as it detonated. In turn, this would mean that a cartridge of this type would be able to propel a bullet at speeds comparable to those of "magnum" cartridges of the same caliber using significantly less powder.Dimensions
The dimensions of the basic case are:- Rim diameter (at base): .535 in. (13.59 mm)
- Outside diameter (at base): .555 in. (14.10 mm)
- Inside diameter (of case): .538 in. (13.67 mm)
- Maximum case length: 2.10 in. (53.34 mm)
The WSM family of cartridges are Delta L problem
Delta L problem
The delta L problem is a condition that occurs regarding certain firearms chambers and their practical incompatibility with ammunition made for the corresponding chambering....
cartridges, meaning they can present unexpected chambering and/or feeding problems. The Delta L problem
Delta L problem
The delta L problem is a condition that occurs regarding certain firearms chambers and their practical incompatibility with ammunition made for the corresponding chambering....
article explains this problem in more detail.
Variants
The 300 WSM was the first of the new class of short magnums to see wide use. All of the WSM cartridges released to date have proven popular for thin-skinned game up to the size of elkElk
The Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...
and African plains game, the .325 WSM being an excellent cartridge for elk, bison and similar big game.
The cartridges in this family are, in order of development:
| Name | Year of development | Bullet diameter |
|---|---|---|
| 300 WSM | 2001 | .308 in. (7.823 mm) |
| 7 mm WSM 7 mm WSM The 7mm Winchester Short Magnum is a centrefire cartridge developed in partnership with Browning Arms Company and Winchester ammunition, making its debut and introduced to the shooting public in 2001.-Specifications:... |
2002 | .284 in. (7.214 mm) |
| 270 WSM .270 Winchester Short Magnum The 270 Winchester Short Magnum or 270 WSM is a short, unbelted, magnum Cartridge created by necking down the .300 Winchester Short Magnum and fitting it with a .277 caliber bullet... |
2002 | .277 in. (7.036 mm) |
| 325 WSM | 2005 | .323 in. (8.204 mm) |
See also
- List of rifle cartridges
- .300 Remington SA Ultra Mag.300 Remington SA Ultra Mag.300 Remington Short Action Ultra Magnum is a .30 caliber short magnum cartridge that was put on the market shortly after Winchester released its 300 WSM round in 2001.-Performance:...
- Winchester Super Short MagnumWinchester Super Short MagnumWinchester Super Short Magnum, or WSSM is a line of rebated rim bottlenecked centerfire short magnum cartridges introduced by the U.S. Repeating Arms Company...