7.7 Japanese

Byron Pace presents a calibre of interesting origin, and even more intriguing potential

It is a very rare thing indeed that I come across a cartridge I have not referenced before in some shape or form. As I have said previously, the reality of cartridge choice is that most do the same thing as any number of others, and with a choice of three you could likely cover everything on the planet without being over- or under-gunned. Talking of versatility, for deer or antelope proportioned game the 6.5mm and 7mm have a strong heritage, with a long list of fantastic cartridges behind them. Before we get to the European 8mm, the next jump up is the .30cal series of cartridges. Unlike the .30cal, the 8mm has never held much water in the UK. However, rewind back pre-1988, and we also had the British .303, which in its day was a cartridge to be reckoned with.

What most people won’t know is that there is another .303-based cartridge, which can surprisingly hold its own against the modern .308 Win. I present to you the 7.7 Japanese. In Europe this cartridge was known as the 7.7×58 Japanese Arisaka, adopted by the Japanese army in 1939 to replace their standard issue, lacklustre 6.5mm cartridge. As a rather confusing occurrence for the Japanese during the war, they ended up having both cartridges in commission. The 7.7 was chambered in a re-design of their standard Type 38 rifle, which became the Type 99 Arisaka. Few examples of these rifles survive today, with most lost after Japan surrendered to the Allied forces. All confiscated arms and ammunition were dumped in Tokyo harbour, never to be seen again. What is important to note for collectors of old rifles is that although Japanese-built rifles were well made, their last push for defence saw a number of Type 99 rifles going into commission without being heat treated, as they rushed to arm their soldiers. This left the rifles inherently weak and dangerous to use.

The 7.7 cartridge uses the same .311 calibre bullet as the .303 British, and as far as the case design goes, there isn’t much in it when compared to the 8×57 apart from being necked down further. Due to rifle build limitations of the time, the 7.7 Japanese factory ammo was loaded to offer almost identical performance of the .303 British. Even today, the very few ammo makers that produce the round (Norma being the primary), under-load the cartridge due to the circulation of old rifles. This doesn’t fully represent what the cartridge is capable of, and with homeloads an extra 150fps is easily achievable. Bear in mind however, that you probably don’t want to try this in an old rifle. Another limiting factor by comparison with today’s modern ammunition is the restricted availability of projectiles for the cartridge, with a very small number of people hunting or shooting the old .311 calibre bullet in any shape or form.

Just to show you what the cartridge could offer, let’s for a moment ignore the pressure limitations of the vintage arms traditionally used to shoot the cartridge. Injecting some modern technology, we can allow the chamber pressures to equal a standard .308 Win. Here we get to see some interesting results. Loaded with some Reloader 17 at max fill, we sit comfortably under the max pressure while pushing a 150gr bullet in excess of 3,000fps. Compare that to a Federal 150gr factory load with a MV of 2,840fps and you can see that the capabilities of the calibre were not constrained by the cartridge design. To complete the comparison, this results in a 7.2in drop for the Japanese cartridge at 300 yards with a 200-yard zero. The aforementioned .308 Win would drop 7.8in.

Of course, the same could be said of a number of older cartridges where the same logic could be applied. It is interesting to note at least that what we class as today’s golden standard had been essentially achieved long before. The difference is that, at the time, they weren’t able to realise its potential. One caveat to that is that undoubtedly some case designs will not easily hold the pressures modern cartridges will sustain, but even still, it is possible to get a lot more from some of the golden oldies than may be initially suggested.

This cartridge will only ever now be an interest piece, and I would be very surprised to ever find a modern rifle chambered in the calibre. There are simply too many similar and available options at hand. Nonetheless, it makes for interesting reading. n