.300 WSM

Infobox Firearm Cartridge
name= .300 Winchester Short Magnum


caption=
origin= USA
type= Rifle
service=
used_by=
wars=
designer= Winchester
design_date=
manufacturer= Winchester
production_date=2001
number=
variants=
is_SI_specs=
parent=
case type=rimless bottleneck
bullet=.308
neck=.344
shoulder=.538
base=.555
rim_dia=.535
rim_thick=
case_length=2.100
length=2.860
rifling=1-10"
primer=Large rifle magnum
is_SI_ballistics=
bw1=150
btype1=SP
vel1=3313
en1=3657
bw2=165
btype2=HP
vel2=3223
en2=3807
bw3=180
btype3=HP
vel3=3095
en3=3830
bw4=200
btype4=SP
vel4=2822
en4=3538
bw5=
btype5=
vel5=
en5=
test_barrel_length=24"
balsrc= [http://www.accuratepowder.com/data/PerCaliber2Guide/Rifle/Standarddata(Rifle)/308Cal(7.82mm)/300%20WSM%20Winchester%20Short%20Magnum.pdf Reloading data at Accurate Powder]

.300 Winchester Short Magnum (also known as .300 WSM, commonly pronounced as "Whizzum") is a .308 caliber short magnum cartridge that was introduced in 2001 by Winchester. [http://www.chuckhawks.com/subscribers/rifle_cartridge_page/300WSM.htm The .300 WSM (Winchester Short Magnum) by Chuck Hawks (subscriptions req)] ] The cartridge overall length is 72.64mm, cartridge case is 53.34mm in length and the bullet diameter is 7.62 mm (common to all U.S. .30 calibre cartridges). The principle at work in the short magnum cartridge is the advantage of fitting larger volumes of powder in closer proximity to the primer's flash hole, resulting in more uniform, consistent ignition. In field use, this round mirrors the performance of its older counterpart, the .300 winchester magnum, which is based on a modified .375 holland and holland belted magnum casing. The advantages of the newer, shorter round are limited, but worth considering. Most notably, the felt recoil of these rifles is less sharp than the longer, narrower magnums. The wide chamber allows gasses re-entering the bore after the departure of the projectile to decompress slightly before slamming into the inner base of the casing, softening the felt impact. Less important to most rifle shooters is the increase in efficiency of shorter casings, which results in greater inherent accuracy. When addressing this topic, it is useful to consider the true degree of accuracy involved. This degree is fairly minute for most uses, and is primarily important to target shooters, and hunters who rely on a rifle to be capable of extreme long range accuracy. Very few rifle shooters are able to shoot better than their rifles, and as such, this aspect is largely academic. The basic issue at hand is that this cartridge is in a class that is already filled with numerous choices in similarly performing rounds, and has little to distinguish it but nominal increase in accuracy, and lighter felt recoil. The .300 WSM is, however, the most modern .30 caliber cartridge in the magnum class, using the physics involved to advantage, and is therefore the best choice for purely academic reasons.

Use & Performance

.300 WSM is used in the Western United States for elk, mule deer, and whitetail and on the plains, where long range shooting is a must. Also, although relatively new, the 300 WSM has already had some success in benchrest shooting. As with all high speed large game rounds, bullet construction plays a major role in terminal ballistic performance, and is far too complex to enter in this space. [ [http://www.iowa1000ydbenchrest.com/2006%20results/Match%2010%20%20%202006.htm Iowa IBS 1000 Yard Match Results - Aug 2006] ] [ [http://www.montana1000yardbenchrestclub.com/ShootResultsAugust2006.htm Montana Northwest 1k yard Club Results - Aug 2006] ]

Muzzle velocity

* 10.69 g (165 gr) Full Metal Jacket(FMJ): 3,125 ft/s
* 11.66 g (180 gr) Full Metal Jacket(FMJ): 2,970 ft/s

Comparison

ee also

* .300 Remington Short Action Ultra Magnum
* .300 Winchester Magnum
* Winchester Short Magnum
* List of firearms
* List of handgun cartridges
* List of rifle cartridges
* List of individual weapons of the U.S. Armed Forces
* 7 mm caliber
* Delta L problem

References

* [http://www.stevespages.com/jpg/cd300winchestershortmagnum.jpgCartridge dimensions at Steve's Pages]

External links

* [http://www.chuckhawks.com/300WSM.htm Chuck Hawk's 300 WSM page]
* [http://www.reloadbench.com The Reload Bench]