270 Winchester Short Magnum | ||||||||||||||||||||
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270 WSM cartridge | ||||||||||||||||||||
Type | Rifle | |||||||||||||||||||
Place of origin | USA | |||||||||||||||||||
Production history | ||||||||||||||||||||
Designer | Winchester | |||||||||||||||||||
Designed | 2002 | |||||||||||||||||||
Produced | 2002 | |||||||||||||||||||
Specifications | ||||||||||||||||||||
Parent cartridge | .300 WSM | |||||||||||||||||||
Case type | Rimless, bottleneck | |||||||||||||||||||
Bullet diameter | .277 in (7.0 mm) | |||||||||||||||||||
Neck diameter | .3140 in (7.98 mm) | |||||||||||||||||||
Shoulder diameter | .5381 in (13.67 mm) | |||||||||||||||||||
Base diameter | .5550 in (14.10 mm) | |||||||||||||||||||
Rim diameter | .535 in (13.6 mm) | |||||||||||||||||||
Rim thickness | .054 in (1.4 mm) | |||||||||||||||||||
Case length | 2.100 in (53.3 mm) | |||||||||||||||||||
Overall length | 2.860 in (72.6 mm) | |||||||||||||||||||
Rifling twist | 1-10" | |||||||||||||||||||
Primer type | Large rifle magnum | |||||||||||||||||||
Maximum pressure | 65,000 psi (450 MPa) | |||||||||||||||||||
Ballistic performance
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Test barrel length: 24" Source(s): "Shooting Times" [1] / Accurate Powder [2] |
The 270 Winchester Short Magnum or 270 WSM is a short, unbelted, magnum Cartridge (firearms) created by necking down the .300 Winchester Short Magnum and fitting it with a .277 caliber bullet. The correct name for the cartridge, as listed by the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI), is 270 WSM, without a decimal point.[3]
Overview[]
When it was introduced, the 300 WSM sported a new case that showed a lot of promise for uses in other calibers. In 2002 Winchester introduced new cartridges in its Winchester Short Magnum family, including the 7 mm WSM and 270 WSM. This new .270 cartridge was the third commercial .270 ever produced, and the first one in 60 years.[1]
The 270 WSM is an improvement over the older 270 Winchester providing higher velocity with bullets of the same weight, and thus a flatter trajectory and more energy. Velocities tend to be about 250 ft/s (76 m/s) faster, in a cartridge that is shorter and can therefore be used in a shorter action for a more compact rifle if desired.
See also[]
- List of rifle cartridges
- 7 mm caliber
- 6.8 mm SPC
- Delta L problem
References[]
- ↑ 1.0 1.1 Pearce, Lane (October 2007). "Nosler's Model 48 Sporter and the .270 WSM". pp. 44–46. http://www.shootingtimes.com.
- ↑ "270 WSM reloading data" from Accurate Powder
- ↑ Sporting Arms and Ammunition Manufacturers' Institute
External links[]
- The 270 WSM by Chuck Hawks
- 270 WSM Accuracy in Browning X-Bolt
The original article can be found at .270 Winchester Short Magnum and the edit history here.