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Trivia Hunt - Looking For Information On Downloaded 7.62x51 Used By Japanese And Spanish Login/Join 
Gracie Allen is my
personal savior!
posted
So apparently 'way back in the dark old days following WWII, Japan and Spain both adopted the 7.62x51 as their service cartridge for the Type 64 rifle (Japan) and CETME C (Spain) respectively.

Can anyone suggest a good source of information on these two loadings? I'm kinda curious as to bullet weight and muzzle velocity, but information on the research and thinking that went into the Japanese and Spanish cartridges would be great. I'm willing to believe my google-fu sucks, but all I've found online is conflicting information about the Japanese bullet's velocity (700 to 715 meters per second) from the 64's 17.7" barrel.
 
Posts: 25004 | Location: Deep in the heart of the brush country, and closing on that #&*%!?! roadrunner. Really. | Registered: February 05, 2008Reply With QuoteReport This Post
Fighting the good fight
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Can't help you on the Japanese loading, but there's some useful info on the lighter CETME-NATO loading in R. Blake Stephens' "Full Circle: A Treatise on Roller-Locking".


The CETME rifle prototypes had originally been designed around a 7.92x41mm loading, and then changed to a 7.62x41mm load during development. When it was then requested in 1955 to convert the design to use the new 7.62x51mm NATO load, the designers at CETME objected, stating that the CETME was intended for use as an assault rifle with an intermediate cartridge, and the excessive recoil energy of the full power 7.62 NATO loading in such a light rifle would make it nigh-uncontrollable on full auto, which is what they had been trying to avoid by going with the intermediate x41mm cartridges to begin with.

However, the designers at CETME attempted a compromise, coming up with the "CETME-NATO" load in 1955-1956, to allow for their CETME rifle design to use ammo with standard 7.62 NATO dimensions yet a lower recoil impulse. This CETME-NATO loading used a 112.6 grain plastic/lead-cored bullet going 760 m/s at the muzzle, compared to the standard NATO load with a 143.5 grain lead-core bullet going 770 m/s at the muzzle. This results in the CETME-NATO load having similar velocity and ballistic trajectory to full power 7.62 NATO, but ~25% less energy and noticeably less recoil impulse.

The CETME Model A rifle was then adopted by the Spanish in 1957, and was designed only for use with the CETME-NATO loading. This early Model A was quickly replaced by the Model B the next year in 1958, which while still intended for use primarily with the lighter CETME-NATO round, was capable of using full power 7.62 NATO as well. A few years later in 1964, the Spanish dropped the CETME-NATO load altogether, and standardized on just 7.62 NATO with the adoption of the CETME Model C.

So the Spanish only used this lighter CETME-NATO loading for ~7 years with their CEMTE Model As and Model Bs, and for only ~1 year exclusively.



If you're interested in the history of a wide variety of prototype and production firearm designs utilizing the roller-locking system, I strongly recommend picking up a copy of this book. (Unfortunately, it's out of print, so copies have gotten fairly pricey.)

This message has been edited. Last edited by: RogueJSK,
 
Posts: 26734 | Location: Northwest Arkansas | Registered: January 06, 2008Reply With QuoteReport This Post
Gracie Allen is my
personal savior!
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I'll be danged. About 112 grains traveling around 2500fps sounds a lot like the 6.8 SPC. Thanks for the information. I'll keep an eye out for a copy of the book - there's this strange confluence of old folks and college kids in the area, which means there's a good Half Price Books nearby and you can occasionally find some good deals on good gun books. As you can tell, I'd originally thought the C was meant for the reduced loading.
 
Posts: 25004 | Location: Deep in the heart of the brush country, and closing on that #&*%!?! roadrunner. Really. | Registered: February 05, 2008Reply With QuoteReport This Post
Fighting the good fight
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I did a little poking around, and you're right... Details on the Japanese reduced recoil 7.62 NATO load are definitely very sketchy. Best I can tell, it used a ~140 grain bullet at 715 m/s. That's roughly a 5% reduction in bullet weight and a 15% reduction in velocity compared to the standard M80 NATO load. As with the CETME-NATO load, the intent was reportedly to allow it to be more controllable on full auto.

Unfortunately, I don't know of any definitive sources for in-depth information on post-WW2 Japanese firearms and ammunition. There likely isn't much interest/demand for such, since those firearms aren't available to collectors.


Regarding full auto controllability: The designer of the CETME, Gunther Voss, had some strong feelings and frustrations about the 7.62 NATO round. His initial intent was for the CETME to be utilized as a true assault rifle, allowing soldiers to fire fairly accurately in automatic from the shoulder by using an intermediate cartridge patterned along the line of the WW2-era 7.92x33, hence why he initially designed the CETME in 7.92x41mm and later 7.62x41mm loads. However, NATO made the decision to adopt a full power rifle cartridge nearly as powerful as .30-06 or 8mm Mauser, yet still wanted to be able to utilize their rifles in an assault rifle role, which Voss recognized from the start was a contradiction. Voss warned from the get-go that 7.62 NATO wouldn't be controllable in full auto from the shoulder, and believed that they really should utilize an intermediate cartridge (like the Eastern Bloc countries had already adopted in 7.62x39), only to be stymied when NATO pushed ahead in their standardization of 7.62 NATO, mainly at the insistence of the US.

Shortly afterwards, everyone else had the same realization at which he had already arrived, that 7.62 NATO rifles couldn't be utilized effectively in an assault rifle role. (Duh.) There were a couple attempts at these Spanish/Japanese reduced recoil loads to bring it a little more in line with an intermediate cartridge and make it more controllable, but the various NATO states eventually started disabling full auto on their 7.62 NATO rifles and/or jumping ship to the 5.56mm intermediate cartridge in entirely different designs within a short time afterwards.

Voss felt that the CETME (and the FAL, M14, et al) should have been true assault rifles in an intermediate loading from the start, and would have been if they'd only listened to him! But despite them not being true assault rifles, the CETME (and its later iteration G3) still had a respectable service history.
 
Posts: 26734 | Location: Northwest Arkansas | Registered: January 06, 2008Reply With QuoteReport This Post
Gracie Allen is my
personal savior!
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The interesting thing to me (and what got me started on this mess) was that what information I could find suggested to me that both Spain and Japan went for what were essentially souped-up versions of the 7.62x39 rather than reduced versions of full-power battle cartridges. That jibes with the idea of controllable automatic fire. But since neither Japan or Spain (to the best of my knowledge) ever went to war with those loads, I was kinda curious as to what was expected of those loads if they were ever used in combat.

Incidentally (if you happen to know off the top of your head), wasn't the FAL originally intended to be chambered for something like the .270 Brit that the Brits originally intended for their earliest bullpup design?

Also incidentally, if you're ever looking for a rabbit hole, the Japanese basically never say anything about anything. I've been trying to find out just about anything about the involvement of Japanese Intelligence in Mexico prior to WWI (Japanese operatives were "sewing leather hand grenades" for the Carranzistas during the whole Plan De San Diego fracaso), and there's nothing out there in English beyond a passing reference in one of Harris and Sadler's books.
 
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quote:
Originally posted by Il Cattivo:
Incidentally (if you happen to know off the top of your head), wasn't the FAL originally intended to be chambered for something like the .270 Brit that the Brits originally intended for their earliest bullpup design?


The FAL was originally designed for 7.92x33mm. The British tested it in 7.92 Kurz and liked it, then requested FALs chambered in their upcoming 7x43mm/.280 British (actually .276 caliber) intermediate cartridge for further testing, alongside their homegrown EM2 bullpup rifle design.

The British and Canadians pushed to get the intermediate .280 load adopted as the NATO standard. The US doggedly wanted a full power .30 caliber round, which would eventually become 7.62 NATO. The US, being the main superpower and economic powerhouse of NATO at the time, won out.

The British abandoned both the EM2 and the .280 load, and adopted the FAL in 7.62 NATO.
 
Posts: 26734 | Location: Northwest Arkansas | Registered: January 06, 2008Reply With QuoteReport This Post
Gracie Allen is my
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There we go, thanks! I guess they were still sore about the EM2, and that's why they insisted on going with the SA80 - which, apparently, has little otherwise to recommend it.
 
Posts: 25004 | Location: Deep in the heart of the brush country, and closing on that #&*%!?! roadrunner. Really. | Registered: February 05, 2008Reply With QuoteReport This Post
Fighting the good fight
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The SA80 debacle has a number of different facets. There's a great reference book called "The Last Enfield" if you'd like to know more. It also goes into some of the background about earlier British bullpups like the EM2.




There's also a soon-to-be-released new text on all the various British bullpups called "Thorneycroft to SA80", which is currently being printed as we speak, and should be released within a couple months.

https://www.headstamppublishin...a80-standard-edition
 
Posts: 26734 | Location: Northwest Arkansas | Registered: January 06, 2008Reply With QuoteReport This Post
Fighting the good fight
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quote:
Originally posted by Il Cattivo:
The interesting thing to me (and what got me started on this mess) was that what information I could find suggested to me that both Spain and Japan went for what were essentially souped-up versions of the 7.62x39 rather than reduced versions of full-power battle cartridges. That jibes with the idea of controllable automatic fire. But since neither Japan or Spain (to the best of my knowledge) ever went to war with those loads, I was kinda curious as to what was expected of those loads if they were ever used in combat.


The 7.62x41mm that was created in early CETME development is kind of a "quasi-7.62x39", much like the CETME's original 7.92x41mm was a "quasi-7.92x33mm Kurz". But that's not the 7.62x51mm CETME-NATO load that the Spanish adopted with the CETME Model A. The CETME-NATO is decidedly a "light 7.62x51mm", and not at all a "souped up 7.62x39".

And the Spanish did "go to war" with their light CETME-NATO load, using it in their CETME As and Bs during their colonial war in Western Sahara against Moroccan insurgents from 1957-1958, known as the Ifni War. It reportedly performed well in combat.




Similarly, the Japanese load was a "light 7.62 NATO", not a "souped up 7.62x39". However, I highly doubt the Japanese "light NATO" load ever "went to war", especially since it was only recently - starting in the mid-2000s - that the JSDF was authorized to take part in stuff like international peacekeeping missions. Before that fairly recent development, they were very much strictly (as the name states) a "Self Defense Force" for Japan. They are barred by the post-WW2 Japanese constitution from partaking in offensive military action, or resolving international disputes through military conflict. Their focus is national defense.
 
Posts: 26734 | Location: Northwest Arkansas | Registered: January 06, 2008Reply With QuoteReport This Post
Freethinker
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Interesting stuff. Thanks to all.




To argue with a man who has renounced his reason is like giving medicine to the dead.
— Thomas Paine
 
Posts: 43387 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
half-genius,
half-wit
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quote:
Originally posted by Il Cattivo:
There we go, thanks! I guess they were still sore about the EM2, and that's why they insisted on going with the SA80 - which, apparently, has little otherwise to recommend it.


Having served with the penultimate version of the SA80, the L85A2, I can report to you that I have yet to meet a Tom or Bootneck who didn't think it was the dog's danglies. Much was done by Heckler & Koch, when it was owned by BAe, and much has been done since. For a debunk of the 'it's a piece of shite and is always falling to pieces at the wrong moment' I earnestly suggest that you do a little research to find the truth. The new version is even better, learning from the experiences of Afghanistan in particular. If you have minute, please read this - but if you don't, it won't matter to me - it's very hard to make good a bad rep, especially one held by people who may never have actually had to use the gun in combat.

Quote - The SA80 A2 ]we call it the L85A2] is being phased out for a new and improved SA80 A3. The Grenadier Guards, who have been the first infantry battalion to fire the new weapon system, have been putting some of the new features to the test. This year sees them deploy on three separate operational tours on OP TORAL to Kabul, OP TRENTON to South Sudan and OP SHADER in Iraq. The busy deployment period sees them adapt to three different theatres where they will be doing three completely different jobs. Training has therefore been paramount and helped them get to grips with a number of differences in the weapon systems.

Perhaps the most noticeable difference is the ‘Flat Dark Earth’ paint with Cerakote coating. These features minimise both the visual and infra-red spectrums allowing the operator to stay unseen. They also give a specialist resistance to weathering and abrasion - important for an army required to complete their tasks in any number of conditions.

This paint job extends to the Picatinny Rail which is welded to the A3 body’s upper receiver. The handguard is also new and supports the Picatinny Rail that sits on the upper receiver. This Picatinny Rail sits on all sides and allows the attachment of in-line night optics, hand grips and other attachments that can increase the potency of the weapon system. The handguard is also free floating, meaning that when the weapon is fired the barrel can resonate freely. This further increases the exactness of a weapon system which is already accurate out to 300m when deployed individually.

In all, the changes allow soldiers to better carry out the varied and diverse tasks that are being asked of them in the modern army. As shown by 1st Battalion Grenadier Guards, who have an exciting 2018 ahead of them.

Defence Minister Guto Bebb* said: “This multi-million-pound upgrade will give our Army a lighter, more hardwearing, better-camouflaged combat rifle so our soldiers can perform on the frontline of some of the most dangerous locations across the world.

“This investment is also a boost to Nottingham’s highly-skilled gun-makers who proudly support our troops in their task to protect our country in the face of intensifying threats."

* In case the name Guto attracts any unnecessary comment from those unfamiliar with the name, be advised that Guto is a Welsh given name; it can be the diminutive form of Gruffudd, a name itself derived from Latin Augustus, from the time of the Roman occupation.
 
Posts: 10302 | Location: UK, OR, ONT | Registered: July 10, 2003Reply With QuoteReport This Post
Charmingly unsophisticated
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That SA80A3 looks vaguely Tavorish. Big Grin


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