.308 Norma Magnum

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.308 Norma Magnum
308 Norma Magnum.JPG
.308 Norma magnum cartridge.
Type Rifle
Place of origin Sweden
Production history
Designer Nils Kvale, Norma
Designed 1960
Manufacturer Norma
Produced 1960 to 1961 components only, 1961 to present as loaded ammunition
Specifications
Parent case .338 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 2,953 ft/s (900 m/s) 3,486 ft·lbf (4,726 J)
180 gr (12 g) Swift A-Frame 2,953 ft/s (900 m/s) 3,486 ft·lbf (4,726 J)
Source(s): http://www.norma.cc

The .308 Norma Magnum (7.62x65mmBR) cartridge was created by Nils Kvale at Norma, Sweden. Like the larger .358 Norma Magnum it is based on the .300 H&H Magnum.[1] The length of the case is the longest that would fit in a standard Mauser action. While it appeared to have a bright future initially, it was soon superseded in popularity by the .300 Winchester Magnum. The first, and one of the few, manufacturers to offer rifles in .308 Norma Magnum was Schultz & Larsen of Denmark and they still are.

In the late 1940s Kvale designed a wildcat called 8mm Kvale. It was intended for use in the German surplus 8mm Mauser M98 that flooded the American market after the war and was therefore nicknamed 'Poor Man's Magnum'. Kvale used the case from the .300 H&H Magnum and reduced the rim diameter so it would fit the bolt of a Mauser M98. The lessons learned from this cartridge were put into the .308 and .358 Norma 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 headspacing.

Notes[edit]

  1. ^ Kvale, Nils; Kulor, krut och älgar. Norma, Åmotfors, 1963.

References[edit]