6.5×55mm

6.5×55mm
6.5×55mm
Type	Military Rifle
Place of origin	Norway / Sweden
Service history
Used by	Norway, Sweden
Production history
Designed	1891
Produced	1894
Specifications
Bullet diameter	6.71 mm (0.264 in)
Neck diameter	7.60 mm (0.299 in)
Shoulder diameter	11.04 mm (0.435 in)
Base diameter	12.20 mm (0.480 in)
Rim diameter	12.20 mm (0.480 in)
Rim thickness	1.50 mm (0.059 in)
Case length	55.00 mm (2.165 in)
Overall length	80.00 mm (3.150 in)
Case capacity	3.75 cm³ (58 gr H2O)
Rifling twist	220 mm (1-8.66 in)
Primer type	large rifle
Maximum pressure	380 MPa (55,000 psi)
Ballistic performance
Bullet weight/type	Velocity	Energy
100 gr (6.5 g) HP	3,183 ft/s (970 m/s)	2,250 ft·lbf (3,050 J)
120 gr (7.8 g) BT	2,812 ft/s (857 m/s)	2,108 ft·lbf (2,858 J)
140 gr (9.1 g) SP	2,651 ft/s (808 m/s)	2,185 ft·lbf (2,962 J)
160 gr (10 g) RN	2,524 ft/s (769 m/s)	2,264 ft·lbf (3,070 J)
Source(s): Hodgdon

6.5×55mm or 6.5×55mm SE (C.I.P.) (also known as 6.5×55mm Krag, 6.5×55mm Swedish Mauser or 6,5×55mm Mauser) is a rifle cartridge developed in 1891 for use in the new rifles then under consideration by the Swedish-Norwegian Kingdom. The two nations had independent armies. Consequently, the normal procedure at that time was for their respective governments to use the same ammunition and then purchase small arms of their choice. Norway adopted the Krag-Jørgensen rifle, while Sweden adopted a Mauser rifle design. The cartridge has a smaller bullet diameter and lower recoil than other full-power rifle cartridges, but thanks in part to its roomy case and heavy bullet has proven more successful than other first-generation smokeless-powder military cartridges of similar size such as the 6×60mm US Navy, 6.5×54mm Mannlicher-Schönauer, 6.5×53mm Dutch Mannlicher, 6.5×52mm Carcano and 6.5×50mm Arisaka.

Development

Early ammunition was loaded with a 10.1 gram (156 grain) long round-nosed bullet (B-projectile) with a muzzle velocity of 700 m/s (2300 ft/s), while later rounds (from 1941 onwards) used a 9.1 gram (140 grain) spitzer bullet (D-projectile) with a muzzle velocity of 800 m/s (2625 ft/s).

Service

Norway

Norwegian Krag-Jørgensen Model 1894 rifle

The 6.5×55mm cartridge was used by Norway in the Krag-Jørgensen rifle and in the Madsen machine gun, as well as in several prototype self-loading rifles.

Sweden

Swedish Mauser Model 1896 rifle

Swedish Model 1942 self-loading rifle (Ag m/42)

In Swedish service, the 6.5×55mm cartridge was used in the Model 1894 carbine, the Model 1896 and Model 1938 rifles and the Ag m/42 semi-automatic rifle. It was also used in several light and medium machine guns such as the Browning BAR, Kg/1940 Light machine gun, Bren Gun, FN MAG, Browning M1917, Browning M1919 and Schwarzlose. The FN MAG was eventually returned to its original 7.62×51mm NATO calibre when the Swedish armed forces switched to that cartridge as its standard during the post-World War II era.

Sporting use

The 6.5×55mm cartridge is highly esteemed as a hunting round in Europe (particularly in Scandinavia), and North America. It is used for harvesting most kind of game including reindeer and moose in Scandinavia, while in most other countries it is used for taking deer and other medium-sized game. Sportsmen who favor the round laud the combination of low recoil coupled with the cartridge's inherent accuracy and superb penetrative qualities.

European rifle makers including Sauer, Blaser CZ, Steyr and Mauser offer sporting rifles chambered for this cartridge, as does the Finnish arms manufacturer SAKO/Tikka, while ammunition manufacturers such as Norma, Lapua, Prvi Partizan and Hornady offer loadings of the 6.5×55mm round that are designed for use only in modern hunting rifles that can tolerate higher chamber pressures. These modern loadings should never be used in older military rifles.^{[citation needed]}

Expanding bullet loaded in a 6.5×55mm before and after expanding. The long base and small expanded diameter show that this is a bullet designed for deep penetration on large game. The bullet in the photo traveled more than halfway through a moose before coming to rest, performing as designed.

The cartridge is also used in the Sauer 200 STR (Scandinavian Target Rifle).

The 6.5×55mm cartridge was widely used in biathlon competition until 1975 (when it was replaced by the .22 Long Rifle (.22 LR) rimfire cartridge), because of its inherent accuracy and historical popularity with the Scandinavian nations who have dominated this sport.

Chamber differences

6.5×55mm Swedish Mauser cartridge dimensions. All sizes in millimeters (mm) plus Imperial (inches).

Due to different interpretations of the standard, i.e. the standards of manufacturing using maximum chamber in the Krag vs. minimum chamber in the Swedish Mauser, a small percentage of the ammunition produced in Norway required a heavy push on the bolt handle to chamber in the Swedish Mauser rifle. After the rumor of this difference first surfaced in 1900, it was examined by the Swedish military. They declared the difference to be insignificant, and that both the Swedish and Norwegian ammunition was within the specified parameters laid down for the 6,5×55. Despite this finding, the Swedish weapon-historian Josef Alm repeated the rumor in a book in the 1930s, leading many to believe that there was a significant difference. The CIP MAP for the 6.5 × 55 is 380 MPa (55000 PSI). SAAMI MAP for this cartridge is 46,000 CUP or 51000 PSI. All Swedish Mauser actions were proof-tested with a single 6.5 × 55mm proof load developing approximately 55,000 CUP (66,000 psi).

See also

• List of rifle cartridges
• 6 mm caliber

References

• Accurate Smokeless Powders Loading Guide Number Two (Revised), Book by Accurate Arms Co, Wolfe Publishing, 2000 p. 229
• 6.5×55mm cartridge dimensions
• CIP CD-ROM Edition 2003
• 6.5×55mm ballistic history