7.7x58 (7.7 Japanese)

History

Contrary to Hollywood’s portrayal of a culture bound by tradition and unwilling to embrace new technologies, the Japanese Samurai eagerly adopted firearms.  In 1543, a Portuguese vessel was shipwrecked off the Japanese island of  Tanegashima. In exchange for aid, Portuguese sailors gifted matchlock muskets to a local lord, introducing the Japanese to firearms.  By 1549, Japanese armorers were mass producing their own matchlock arms ranging in caliber from 8.5mm (.335”) up to a massive 48mm (1.89”).  The Matchlock (Teppu in Japanese) became integral to the Samurai art of warfare, utilized in intricate and ingenious offensive and defensive strategies.
 
As firearms technologies evolved, Japanese military officials traveled to Europe assimilating designs, perfecting each design in Japan.  By the mid 1800’s, Japan had adopted the Murata single shot bolt action rifle which by 1889 had become tube magazine loaded in the caliber 10x60 rimmed. 
 
With the advent of smokeless powder, the Japanese opened a commission in 1894 to find a replacement for the Murata rifle and cartridge.  Lead by Colonel Nariake Arisaka and weapons designer Kijiro Nambu, Japanese rifles design was again heavily influenced by European innovations.  In 1897 the Japanese imperial army adopted the Type 30 Arisaka rifle.  The Type 30 was chambered for the mild 6.5x50, a semi rimmed cartridge firing a 139 grain .260” bullet at 2500fps from the 32” Arisaka barrel. 
 
Following the Russo-Japanese war of  1905 the Type 30 rifle was modified and re-designated as the Type 38 Arisaka. The Type 38 was based heavily on the famous Mauser M1898 rifle however the greater care given to metallurgy and heat treatment of the Type 38 resulted in a rifle action that was even stronger than the already incredibly strong parent design.
 
After conflict with China during the 1930’s, the Japanese military decided a larger caliber cartridge with greater stopping power than the 6.5 was required.  Having had excellent results with the Lewis gun, it was decided that the 7.7mm caliber (.303”) would be extremely suitable but in a rimless rather than rimmed cartridge case.  This resulted in the creation of the 7.7x58 cartridge in 1939.
 
The Type 38 rifle was redesigned to fire the 7.7mm cartridge, the new rifle being designated Type 99 Arisaka. Many Type 38 rifles were also upgraded, bearing the designation Type 38/99.  The 7.7x58 was loaded with a 181 grain bullet giving around 2400fps from the Type 99’s 25.75” barrel.
 
The Type 38 6.5x50 rifle and Type 99 7.7x58 rifle saw service throughout World War Two.  Not adhering to the Hague convention, both Japanese 6.5 and 7.7 projectiles featured heavy jackets towards the tip of the projectile which tapered and became thinner toward the base.  The greater lead content at the rear, made the projectile extremely rear heavy, causing it to tumble on impact- creating horrendous wounds. 
 
After Japan surrendered to Allied forces in 1945, all Japanese stocks of Type 38, Type 38/99 conversions and Type 99 rifles and ammunition were dumped into the Tokyo harbor.  The remaining examples of these arms are those captured by allied forces during the conflict.  Many thousands of rifles were captured and eventually sold on the civilian market. 
 
Although the Type 38 and 99 rifles were extremely strong, Japans last ditch efforts to supply its soldiers with arms during 1945 resulted in some Type 99’s having no heat treatment at all before being put into service. These arms were and are extremely dangerous and shooters contemplating using the Type 99 rifle should have the metallurgy checked by a gunsmith.
 
In the U.S following the Second World War, many Arisaka rifles were rechambered or rebarreled to more readily available cartridge offerings while other rifles remained wall hangers for many years until Norma and finally Graf & Sons produced sporting ammunition for both the 6.5 and 7.7 variants. The Arisaka rifle and/or its chamberings have since maintained a small level of popularity, whether the motivation is simply born out of curiosity or Nostalgia. In other areas of the world, rechambering/rebarreling the Arisaka was far less common, most rifles being maintained in original order.
 

Performance

Readers are reminded that unsafe (no heat treatment) Type 99 rifles may still be in circulation. If you have an Arisaka Type 99 rifle and are in doubt as to its strength, the rifle should be taken to a gunsmith, a discreet file test performed to check for case hardening (recommend bottom of action boss/lug).
 
As a hunting rifle the Japanese Arisaka has some favorable qualities. The action is a self-centering round design similar to the Remington M700. The Arisaka lacks a large flat recoil lug but does feature a small round boss which acts as a recoil lug. The tang (rear of the action) is odd in that it is not a part of the action and instead is screwed to the action. Bridge type scope bases have been fitted to the Arisaka action after bolt handle alteration however many Arisaka rifles have been kept in original condition, hunters utilizing the existing open sights.  In more recent years, many shooters have fitted ‘no-gunsmithing’ scout scope mounts to Arisaka rifles. These attach to the Arisaka’s rear open sight housing without alteration.
 
The 7.7x58 or 7.7 Japanese as it is commonly known, is an effective medium game hunting cartridge.  The case design is essentially the 8x57 necked down to .311”.  Factory ammunition generally duplicates Japanese military loads  which also duplicate.303 British velocities.  Hand loads can be pushed up to 100fps faster with care, duplicating .308 Winchester velocities.
 
Like the .303 British, if using conventional soft point projectiles, the 7.7 Japanese produces identical killing performance to the .308 Winchester.  But with the availability of high BC, high performance .30 caliber bullet designs, the 7.7 cannot achieve the same level of killing performance. At close ranges, the differences are negligible. But as ranges exceed 100 yards, the differences between traditional conventional 7.7 (.311/.312) projectiles and modern enhanced .30 caliber bullets become much more noticeable. 
 
125 grain hand loaded bullets driven at velocities 3000fps produce fast kills on light game out to ranges of around 250 yards (2200fps) with often delayed killing thereafter.
 
Factory 150 grain loads perform best at close to moderate ranges on game weighing less than 90kg (200lb). Hand loaded 150 grain .311/.312 bullets driven at 2750-2800fps produce fast killing on lean bodied deer species out to ranges of around 60 yards (2400fps), with slightly delayed but clean killing down to velocities of 2400-2200fps (150-240 yards) depending on shot placement and body weight resistance. Beyond 240 yards/2200fps, kills can be very delayed, being entirely dependent on shot placement.
,
Factory and hand loaded 174 to 180 grain bullets produce desirable performance on game weighing 90kg (200lb), up to body weights of around 320kg (700lb). Moderate velocities help minimize the risk of bullet blow up. Kills on larger animals can often be delayed due to low impact velocities, though clean killing (wide wounding) can be expected out to ranges of around 300 yards (pointed bullets).
 
The original 6.5x50 is survived by just two loadings, Norma advertise their Alaska 156 grain conventional soft point bullet at 2067fps while Graf & Sons load the 140 grain Hornady Interlock bullet at an advertised 2225fps.  In older worn 32” bores velocities are typically lower than those advertised suffice to say that even at advertised velocities, these loads display no hydrostatic shock, along with limited wounding potential. From a 32” barrel top hand loads using medium through to slow burning powders in the 4064 to 4350 range produce velocities of 2800fps with 120 grain bullets, 2600fps with 140 grain bullets and 2400fps with 160 grain bullets.  In the shorter 19” barreled Arisaka carbine, velocities of 2500fps, 2300fps and 2100fps are achievable with 120, 140 and 160 grain bullets respectively.  This duplicates the performance of the 6.5x54 Mannlicher- Schnoenauer.

   

Factory ammunition

 
The 7.7 Japanese is similarly survived by two factory loadings, Norma produce a 174 grain conventional soft point bullet at an advertised 2493fps while Graf & Sons produce ammunition featuring the 150 grain Interlock bullet at an advertised 2650fps.  Both give velocities around 100fps slower than advertised in older, worn 25.75” Arisaka barrels.  These velocities produce low shock however projectile performance is generally good (wide wounding) when appropriately matched to game body weights.

The 150 grain Interlock is extremely soft and expands readily on light framed game. Best results are obtained out to moderate ranges of 150 to 180 yards (2200fps).  The Norma 174 grain Round nose bullet is very similar in malleability to the Sierra round nosed Prohunter, having a somewhat stout jacket, but when used on large medium game, expands readily and reliably. Due to the round nose design and rapid loss of velocity, this bullet does its best work inside 200 yards.
 

Hand loading

Brass for the 7.7 Japanese is currently available from Norma and Prvi. Hornady made 7.7 brass for many years (used in Graf ammunition) however this is not currently listed among Hornady’s product lines. Brass can also be formed from 8x57 cases very easily.
 
The 7.7 Japanese works extremely well when hand loaded with powders in the fast 4895, (ADI2206H) range through to Varget and 4064 with heavier bullets.  Reloading manuals suggest loads for the 7.7 which duplicate .303 British loads of 2700fps with 150 grain bullets and 2400fps with 174 to 180 grain bullets. Many hand loaders do prefer to stay within these limits to minimize wear on these now collectable rifles. The Arisaka action is however strong enough (with the exception of unsafe non heat treated Type 99 actions) to take higher pressure loads of 2800fps and 2500fps respectively.

The 7.7 utilizes the same bullet diameters as the .303 British. Tight bores will give desirable accuracy with .311” projectiles while loose/worn bores perform better when loaded with Hornady’s .312” projectiles.

Please see the .303 British text for individual bullet performance.
 

Closing comments

Today, it is rare to find a hunter using an Arisaka rifle chambered in 6.5x50 or 7.7x58. Arisaka rifles are occasionally seen at the rifle range in the hands of collectors and those interested in military rifle designs. The 7.7 is certainly an effective hunting cartridge but for the most part it lives on simply out of nostalgia, as a reminder of our recent history.   
 
 

Suggested loads: 7.7x58					Barrel length: 25.75"
No	ID		Sectional density	Ballistic coefficient	Observed  MV Fps	ME Ft-lb’s
1	HL	150gr Hornady Interlock*	.220	.361	2800	2611
2	HL	180gr Prvi (Highland)*	.266	.400	2500	2498

 

Suggested sight settings and bullet paths
1	Yards	100	220	260	300
	Bt. path	+3	0	-3	-7.3
2	Yards	100	198	235	250	300
	Bt. path	+3	0	-3	-4.6	-11.2

 

No	At yards	10mphXwind	Velocity	Ft-lb’s
1	300	9	2089	1453
2	300	9.2	1910	1458

 
 
*Sight height .5” (open sights).
 
 
 

7.7x58	Imperial	Metric
A	.473	12.01
B	.472	11.99
C	23 deg
D	.430	10.92
E	.338	8.58
F	1.872	47.55
G	.300	7.62
H	2.283	58
Max Case	2.283	58
Trim length	2.273	57.7

 
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