6.5x50mm Arisaka

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6.5x50mm SR Arisaka

Type Rifle
Place of origin Flag of Japan Japan
Service history
Used by Japan, Russia, United Kingdom, China, North Korea, South Korea, Thailand, Finland, Indonesia
Wars World War I, Second Sino-Japanese War, World War II
Production history
Produced 1897
Specifications
Case type Semi-rimmed, bottlenecked
Bullet diameter 6.705 mm (0.2640 in)
Neck diameter 7.34 mm (0.289 in)
Shoulder diameter 10.59 mm (0.417 in)
Base diameter 11.35 mm (0.447 in)
Rim diameter 11.84 mm (0.466 in)
Rim thickness 1.143 mm (0.0450 in)
Case length 50.39 mm (1.984 in)
Overall length 75.69 mm (2.980 in)
Primer type Large rifle
Ballistic performance
Bullet weight/type Velocity Energy
139 gr (9.0 g) FMJ 2,510 ft/s (770 m/s) 1,928.7 ft·lbf (2,615.0 J)
Test barrel length: 800 mm

The 6.5x50mm Semi-Rimmed Japanese cartridge was adopted by the Imperial Japanese Army in 1897 along with the Type 30 Arisaka Infantry Rifle and Carbine. The new rifle and cartridge replaced the 8x52mm Murata round used in the Type 22 Murata Rifle. In 1902 the Imperial Japanese Navy chambered its Type 35 Rifle for the cartridge as well. In 1905, the round also came to be offered in the Type 38 Arisaka Infantry Rifle and Carbine, both of which obsoleted the Type 30 in Imperial Army service. Type 44 Cavalry Carbines, first adopted in 1911, were also chambered in 6.5x50mm.

Contents

[edit] History

Early 6.5x50mm cartridges had a cupro-nickel round nosed bullet weighing 160 grains (10 g) fired with approximately thirty two grains of smokeless powder. This was later changed with the adoption of the Type 38 when Japan, in line with the other great powers around the same time, changed to the pointed or spitzer bullet in the first decade of the twentieth century. The Type 38 spitzer-bullet round fired a 139-grain (9.0 g) bullet with a powder charge of thirty nine grains for a muzzle velocity of around 2,500 feet per second (760 m/s).

The Type 38 spitzer version of the 6.5x50mm cartridge remained unchanged until after the adoption of the Type 11 Light Machine Gun in 1922. The Type 11 was initial meant to fire standard Type 38 Rifle ball ammunition by means of ordinary five-shot Type 38 stripper clips. Subsequent use indicated that the higher pressures generated by the standard rifle ammunition caused parts wear and breakage in machine guns. It was thus decided to reduce the powder charge of Type 11 6.5 mm ammunition to overcome the problem. This reduced charge 6.5 mm ammunition can be identified by a letter "G" in a circle stamped on the outside of the ammunition packaging which stands for the first letter of genso - the Japanese word for "reduced." This special ammunition was also issued to soldiers carrying the Type 96 Light Machine Gun introduced in 1936 and to snipers issued the Type 97 Sniper Rifle, introduced in 1937. The advantage of the reduced charge ammunition to the sniper aided in his concealment as the reduced charge rounds produced less muzzle flash than standard rounds and thus did not give away the sniper's position.

6.5 gallery ammunition incorporated a paper or wood bullet and dummy rounds as issued to Japanese forces were either all brass rounds or were more commonly red varnished wood with a metal base and rim. Ammunition used in the spigot-type Japanese grenade launchers often have paper bullets and can be identified by staked primers.

[edit] Other 6.5 mm firearms

Other 6.5x50mm long-arms used by Japan included a few Type 13 Mauser rifles produced at Hoten (Mukden) Arsenal in Manchuria, China. These rifles were built on Danish Nielsen-Winther machinery originally for Manchurian warlord Chang Tso Lin beginning in 1924. After Japan took over the arsenal after the Manchurian Incident of 1931 the Type 13 rifle continued to be produced in 7.92x57mm Mauser caliber, but an unknown number were also built in 6.5x50mm. The Type I rifles built by Italy for Japan under the terms of the Anti-Comintern pact from 1939-1943 are in standard 6.5x50 mm Japanese. Their Italian origin should not be taken to mean that these will safely fire the longer, but outwardly similar, 6.5x52mm Carcano round. An unknown number of Dutch M1895 Mannlicher rifles and carbines captured by Japanese forces during the seizure of the Dutch East Indies in 1942 were converted to 6.5x50mm from 6.5x53mm Dutch rimmed caliber.

[edit] Russian usage

After observing the effectiveness of the Type 30 6.5x50mm round as used against them during the Russo-Japanese War of 1904-1905, leading Russian arms designers chambered early Russian semi-automatic rifle designs for the Japanese round. Since the standard Russian military rifle cartridge of the time, the .30 caliber 7.62x54mmR rimmed round, was too powerful and generated excessive recoil in an automatic arm - a 6.5 mm round was seen as more appropriate. Early semi-automatic designs by Vladimir Fedorov utilized 6.5x50 mm including the Fedorov Avtomat rifle which was actually issued to troops, though in small numbers. Later, Russian troops on the Armenian front were issued with Type 38 Carbines given by the Tsar's government. Russians also tended to modify the Type 38s magazine latch, as it was found that gloved hands would sometimes inadvertently nudge the magazine release and dump the ammunition.

[edit] British usage

In 1914 approximately 150,000 Arisaka Type 30 and Type 38 Rifles and Carbines were sold to British forces - mainly the Royal Navy where they were used for training. The 6.5x50mm round was subsequently produced in Britain by the Kynoch company and was officially adopted for British service as the .256 caliber Mk II in 1917. The Arab armies organized by British Captain T.E. Lawrence to fight against the Ottoman Empire during World War I are purported to have been issued with Type 30 Rifles by the British in 6.5 mm though some have opined that the Bedouin forces mainly used captured Turkish Mausers instead. In Seven Pillars of Wisdom, chapter 13, T. E. Lawrence writes, "Later some Japanese rifles, most of them broken, were received. Such barrels as were still whole were so foul that the too-eager Arabs burst them on the first trial." In all, the 6.5x50mm Japanese semi-rimmed round has been used in either Japanese or domestically designed weapons by Japan, Russia, the United Kingdom, China, North Korea, South Korea, Thailand, Finland and Indonesia. Many of the British Naval Arisakas were handed over to the White Russians.

[edit] Finn usage

The Russians, having a surplus of Type 30 and Type 38 rifles from both direct purchase from Japan during WWI and also having captured examples during the Russo-Japanese War, had warehoused some of these rifles in Finland. During the Russian Revolution, many Finns seized the chance for independence and liberated many Arisakas from Russian arsenals. They were used mainly by Finn cavalry and after Finland's independence, experiments were taken to upgrade the Type 38s to 7.92. With parts and ammunition drying up, Finland relegated the Arisaka to the reserves and the merchant marines before trading a large number of them off to Estonia. Finn used Arisakas will have district numbers and an 'S' branded on the stock.

[edit] Today

The cartridge was only available in loaded form to shooters in the United States by Norma of Sweden for many years but now brass cases can be had from Graf & Sons and quality hand-loads made up. Kinematics Research of Tennessee also loads this cartridge, as does Hornady. Bullets are standard .264 caliber.

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