The .243 Winchester Super Short Magnum or .243 WSSM is a
rifle
A rifle is a long gun, long-barreled firearm designed for accurate shooting and higher stopping power, with a gun barrel, barrel that has a helical or spiralling pattern of grooves (rifling) cut into the bore wall. In keeping with their focus o ...
cartridge introduced in 2003. It uses a
.300 WSM (
Winchester Short Magnum
Winchester Short Magnum, or WSM, refers to a family of Rim (firearms), rebated bottlenecked centerfire short magnum Cartridge (firearms), cartridges developed in the early 2000s by the U.S. Repeating Arms Company, the maker of Winchester rifles an ...
) case shortened and necked down to accept a
.243in/6mm diameter bullet, and is a high velocity round based on
ballistics
Ballistics is the field of mechanics concerned with the launching, flight behaviour and impact effects of projectiles, especially weapon munitions such as bullets, unguided bombs, rockets and the like; the science or art of designing and acceler ...
design philosophies that are intended to produce a high level of efficiency. The correct name for the cartridge, as listed by the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI), is 243 WSSM, without a decimal point. Winchester has discontinued the manufacture of 243 WSSM ammunition.
As of the first half of 2016, Winchester/Olin did manufacture and release for sale some WSSM ammunition. The product is only manufactured periodically, often at inconsistent intervals.
Design
The .243 WSSM is an addition to the
Winchester Super Short Magnum
Winchester Super Short Magnum, or WSSM is a line of rebated bottlenecked centerfire short magnum cartridges introduced by the U.S. Repeating Arms Company (''Winchester Inc''). It is a further development of the Winchester Short Magnum concept ...
(WSSM) family of cartridges, which also include the
.223 WSSM and the
.25 WSSM, and the idea behind the .243 WSSM was to develop a compact, higher velocity version of the well-established and internationally popular
.243 Winchester unveiled by Winchester in 1955.
The .243 WSSM was first introduced in 2003.
The .243 WSSM's case is unusually short and fat in profile, contrasting markedly with most other rifle cartridges, and is intended to take advantage of what ballisticians have shown is the more uniform and efficient
burning
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combust ...
of propellant powder when it is held in a short, fat stack by the cartridge case.
Performance
In their ballistics tables,
Winchester
Winchester (, ) is a City status in the United Kingdom, cathedral city in Hampshire, England. The city lies at the heart of the wider City of Winchester, a local government Districts of England, district, at the western end of the South Downs N ...
list a very high muzzle velocity of with a projectile for this cartridge. Based on Hodgdon reloading data typical velocities should range from approximately with a bullet to approximately with a bullet.
The percentage gain in performance over the older .243 Winchester is around 10% or less.
This cartridge is usually used for small game such as
varminting
Varmint hunting or varminting is the practice of hunting vermin — generally small/medium-sized wild mammals or birds — as a means of pest control, rather than as games for food or trophy. The targeted animals are culled because they are cons ...
, and used for animals as large as
deer
A deer (: deer) or true deer is a hoofed ruminant ungulate of the family Cervidae (informally the deer family). Cervidae is divided into subfamilies Cervinae (which includes, among others, muntjac, elk (wapiti), red deer, and fallow deer) ...
.
Advantages
Compared to other factory 6mm sporting cartridges the .243 WSSM is capable of functioning in the
AR-15. Other factory produced 6mm cartridges like the .243 Win and 6mm Rem are both too long for the AR-15 and require the AR-10 platform.
The .243 WSSM is shorter than the .243 Win, giving the .243 WSSM the ability to fit in a super-short action rifle. Thus .243 WSSM rifles can be lighter, have stiffer actions and have faster actions to cycle.
The .243 WSSM gives generally a 10% increase in velocity over the .243 Win.
See also
*
6 mm caliber
This is a list of firearm cartridges which have bullets of a caliber between and .
*''Length'' refers to the cartridge case
Case or CASE may refer to:
Instances
* Instantiation (disambiguation), a realization of a concept, theme, or design
* ...
*
List of rifle cartridges
List of rifle cartridges, by primer type, Caliber, calibre and name.
File:Cartridge Sample 2.jpg, 350px, From left to right: 1 .17 Hornady Mach 2, 2 .17 Hornady Magnum Rimfire, 3 .22 Long Rifle, 4 .22 Winchester Magnum Rimfire, 5 .17/23 SMc, 6 5mm ...
*
Table of handgun and rifle cartridges
This is a table of selected pistol/submachine gun and rifle/machine gun cartridges by common name. Data values are the highest found for the cartridge, and might not occur in the same load (e.g. the highest muzzle energy might not be in the same ...
References
Cartridge Dimensionsat Steves Pages
External links
243 WSSM – The Long-Awaited 6 mm "Answer"?By Bill Prudden
by Chuck Hawks
The Experts Agree The WSSMs are Winners!Browning
The 243 WSSMat Guns & Ammo
Hunting experiences with the 243 WSSM243WSSM.com
{{DEFAULTSORT:243 Wssm
Pistol and rifle cartridges
Winchester Super Short Magnum rifle cartridges