.358 Norma Magnum

.358 Norma Magnum
The .358 Norma Magnum rifle cartridge.
Type	Rifle
Place of origin	Sweden
Production history
Designer	Nils Kvale
Designed	1950's
Manufacturer	Norma
Produced	1959
Specifications
Case type	Belted rimless, bottleneck
Bullet diameter	.359 (9.12)
Neck diameter	.388 (9.45)
Shoulder diameter	.490 (12.45)
Base diameter	.513 in (13.03 mm)
Rim diameter	.531 in (13.5 mm)
Case length	2.520 (64.0)
Overall length	3.346 (85)
Primer type	Large rifle magnum
Ballistic performance
Bullet mass/type Velocity Energy 250 gr (16 g) Bonded SP 2,756 ft/s (840 m/s) 4,217 ft·lbf (5,717 J)

The .358 Norma Magnum (.358 NM or 9.1x64mmBR) is a bolt action rifle cartridge introduced in 1959 by Swedish company, Norma. It is closely related to the smaller-bullet .308 Norma Magnum. Both calibers share the same dimensions of the case head as the .300 H&H Magnum, but have far less body taper, resulting in the same internal capacity in a shorter case. The cartridge case is the longest that will comfortably fit in a standard Mauser action, or any rifle action designed to chamber the 30-06. The .358 NM was the first .35 caliber cartridge commercially developed and sold to the American market since the decline of the .35 Newton in the late 1920s.

Though introduced by a Swedish company, the .358 Norma was designed for American hunters, due to Norma's chief designer Nils Kvale's close contacts with American colleagues. It is intended as a cartridge for the largest of North American game - elk, moose, brown bear, Bighorn Sheep, and bison, and shoots fast and flat enough to be useful to 400 to 500 yards on game the size of American elk (Wapiti). While it is needlessly powerful for deer-sized game, it can be used, at least with the heavier (and therefore slower) .358 bullets on such game without destroying too much meat. It would work well, with properly designed bullets, on most large African species. But laws prohibiting the use of bullets smaller than 0.375-inch (0.95 cm) on dangerous game, in most African countries, limit its use to "plains game," including the largest antelope, the one-ton eland.

Norma took a gamble, introducing the .358 only as new empty cases for handloaders, and chambering-reamer specifications for gunsmiths who made custom rifles—there were no factory rifles available, and it was several months before factory-loaded ammunition appeared. The cartridge proved immediately popular with hunters and custom gunsmiths, and within a year the Danish firm of Schultz & Larsen chambered its Model 65 for the round, and Husqvarna its Series 1600 and 1650 rifles.