.308 Norma Magnum
From Wikipedia, the free encyclopedia
| .308 Norma Magnum | ||
|---|---|---|
| Type | Rifle | |
| Place of origin | Sweden | |
| Production history | ||
| Designer | Norma | |
| Designed | 1960 | |
| Manufacturer | Norma | |
| Produced | 1960 to 1961 components only, 1961 to present as loaded ammunition | |
| Specifications | ||
| Parent case | .300 Winchester Magnum | |
| Case type | Rimless, Belted | |
| Bullet diameter | .308 in (7.8 mm) | |
| Neck diameter | .340 in (8.6 mm) | |
| Shoulder diameter | .489 in (12.4 mm) | |
| Base diameter | .512 in (13.0 mm) | |
| Rim diameter | .530 in (13.5 mm) | |
| Rim thickness | .048 in (1.2 mm) | |
| Case length | 2.56 in (65 mm) | |
| Overall length | 3.30 in (84 mm) | |
| Primer type | large rifle magnum | |
| Maximum pressure | 55,100 psi (380 MPa) | |
| Ballistic performance | ||
| Bullet weight/type | Velocity | Energy |
| 180 gr (12 g) Oryx | 2,464 ft/s (751 m/s) | 2,426 ft·lbf (3,289 J) |
| 180 gr (12 g) Swift A-Frame | 2,576 ft/s (785 m/s) | 2,649 ft·lbf (3,592 J) |
| Source: http://www.norma.cc | ||
The .308 Norma Magnum cartridge was created by Norma of Sweden. It is a .338 Winchester Magnum case necked down to .308. While it appeared to have a bright future initially, it was soon superseded in popularity by the .300 Winchester Magnum.
Cases for the cartridge can be purchased from Norma or made in three ways: Necking up a 7 mm Remington Magnum case, necking down a .338 Winchester Magnum case, or running .300 Winchester Magnum cases through a full-length sizing die. Since the first two options leave the brass a bit short, the third is generally considered to be the best option. Ammunition for this caliber is not cheap (typically US$50–60 for 20 cartridges) and as such it is mainly of interest only to handloaders who own a rifle chambered in this caliber. The cartridge makes use of a belted case for strength.
[edit] See also
[edit] References
 |
This article or section includes a list of references or external links, but its sources remain unclear because it lacks in-text citations. You can improve this article by introducing more precise citations. |
