7.62 NATO duplex?


#1

On page 376 of “The Black Rifle” by Stevens and Ezell, there is a description of a cartridge with a (+) IVI hs and a duplex? bullet consisting of a 5.56mm ball inserted into a hollow nose 7.62. According to the details given, the cartidge came from a box labelled “Test lot 6-duplex”. The cartridge appears to the same to that featured in “The Better Half” in the Jan/Feb 2006 IAA Journal. Does anyone have more information on this bullet design?


#2

Dave, you are asking of a very specific and rare experimental variation that I know nothing about (a 5.56 ball seated in a 7.62 ball).
For those readers of the forum who will be drawn to the 7.62 Duplex heading…as you know there has been “chapter & verse” written about, not just the 7.62 x 51, but all through the 30-06 family and the huge Project SALVO experiments and more recently the ACR (Advance Combat Rifle) trials (in the early 1990’s) with some 5.56 duplex loadings.

My favorite “trivia” when showing off the “common” 7.62 x 51 green tipped duplex is the slightly “canted” base of the trail bullet so as in theory the trail bullet would not “follow” the lead bullet and you might affect two hits (I have read this did not work in practice).

As you have alluded to a rare variation…I am sure there are many rare developmentals that reside in the most advanced of collections.

Multi ball projectiles are fascinating and there is no better way to appreciate them then through the fine work of an expert “sectioner” (Paul Smith…the Better Half)…I have 15+ variations. Sorry I can’t answer the specifics of your question…but I am confident you’ll attract readers…and they may not know there are written “chapter and verse” about this fascinating subject.


#3

I do not have that book and so can’t comment on that exact cartridge but in the 1970s several faked “duplex” rounds were created and sold in this design. There were a variety of exotic loads and a “tracer”( which was not very well thought our since the .223 tracer bullet seated in the drilled out 7.62 nose could not have been ignited ). Many of these were painted in bold colors - which the last time I saw one had faded. These initially came to market through the late Wayne Markov of Norton Ohio. He had met a pair of retired soldiers who had worked with Paul Van Hee when he bought the extensive White and Munhall reference collection. They helped with the moving, set up and sale in a couple of location . Later after the W&M business was done they continued to come up with a variety of “special” loads including these “duplex” variations and poison bullet loaded 7.62x39s. These shells had the bullets removed-the cores removed from the bullets-loaded with actual poison ( according to Woodin lab information) and then the base sealed with melted plastic. The projectile would never have survived firing.

These rounds were so novel and exciting,at the time, that a certain well known collector nearly had to be hospitalized when he realized that he didn’t have enough trade to cover a set from me. It was the first and last time I ever saw a collector actually turn color and break out into sweat. They did come in boxes but I no longer remember them. I am sure that Woodin Lab has the boxes.

These fellows learned that there was money in “experimental” ammunition and made some to market. I bought a couple of each from Wayne before it was determined that they were fakes. I think that Woodin lab has a complete collection of their work in the fake department.

The sectioned sample in “the better half” is the same design as the fakes which I mentioned. I would need to see some official paperwork to believe this story again.


#4

[quote=“Pepper”]
My favorite “trivia” when showing off the “common” 7.62 x 51 green tipped duplex is the slightly “canted” base of the trail bullet so as in theory the trail bullet would not “follow” the lead bullet and you might affect two hits (I have read this did not work in practice).

As you have alluded to a rare variation…I am sure there are many rare developmentals that reside in the most advanced of collections.

Multi ball projectiles are fascinating and there is no better way to appreciate them then through the fine work of an expert “sectioner” (Paul Smith…the Better Half)…I have 15+ variations. Sorry I can’t answer the specifics of your question…but I am confident you’ll attract readers…and they may not know there are written “chapter and verse” about this fascinating subject.[/quote]

For me Duplex and Multi-ball loadings fall into the same group as Flechettes and Trounds - fascinating engineering, lots of pretty variations for collectors but doomed to never be successful in the field. The multi-ball theory seems to follow along the lines of: “the soldier never hits where he thinks he is aiming therefore there is no point in the rifle hitting what he aims at and you may increase his chances by making the bullet(s) go anywhere else except where he aims!” Maybe I am being a little cynical here.

gravelbelly


#5

Of course you are correct and the unfortunate fact is that a soldier in combat is a very poor shot historically. When I designed the ammo display in the WW2 hall of the Smithsonian National Air and Space Museum in Wash DC I wanted to note how many rounds were expended per casualty. I researched the number and it is in the thousands. I have it in my notes someplace from 30 years ago- long story short- they would not let me put that in the display.We (U.S.) and other countries have spent many millions of dollars trying to increase the probability of a hit per shot. The answer has always been the same-shoot more using automatic weapons. The duplex doubles the chance of a hit and a variety of them were tried in our last advanced combat rifle testing BUT they are harder and more expensive to manufacture , increase the weight of the ammo load and the recoil AND the problem of getting them to stay together(the bullets) where you want them and fall apart when you don’t has never been satisfactorally solved. 2 bullets in tandem have to stay together through all sorts of bumps and drops otherwise the rear one drops into the powder load which really messes up the situation. THEN the 2 have to seperate and go their own way to have the desired effect. This is not an easy thing to design. Flechettes work well in larger caliber shells but not in single rifle cartridges. The new METALSTORM technology increases the hit probability greatly but is too cumbersome for small arms use.

In my opinion the development of directed energy weapons will be successful before there will be any meaningfull change in small arms ammunition design AND then(maybe before) the possession of ammunition will be outlawed in the U.S. or controlled as it is in Russia , England and elsewhere.


#6

From Woodin lab: " The real one is from this box (wound test). The fake ones, according to Markov - w. SP & HP bullets, tracer, etc - were made up later by a former employee of Sionics, Inc , and turned up at a Columbus show ca 1971".


#7

I was under the impression that the XM-198 Duplex (7.62x51mm) was fielded and well received, such that it was formally adopted as the M-198. Is this not the case? I can see where the cost could be a factor in it’s widespread use, but would this not be overcome through mass production?

AKMS


#8

INFORMATION FROM FRANK HACKLEY M198 Duplex, yes this was fielded in MLB pack for ground MG both straight M198 and 4-M198 with 1-M25 Tracer and was well received in VN. The problem was that few people in the supply chain even knew it was available but after it caught on was issued in greater numbers. Yes, to second part, certainly mass production could have reduced the cost, which was primarily in the making the two bullets and loading them in the case. In fact both Olin (WRA) and FA had product-improvement projects in the works to reduce the cost of the M198 bullet and loading operation… This same story is being played out today in Iraq with the 5.56mm AP M995 and 7.62mm AP M993, the people on the ground do not even know these rounds exist and are available and they would certainly do better in a urban warfare environment then ball rounds!

The primary reason for not making more M198 was the projected cost of changing the production base facilities for the bullet and loading operations, and this plus the VN war winding down caused interest in this round to fade. There as also an “in-house” conflict between the development community (FA & AMC) and the user (Infantry Board) as to the rounds advantage at short range versus complicating the supply system by issuing another round. In other words, the standard MG pack of Ball M80 & Tracer M25 (4 to 1) could be used in both offense and defense, while the M198 had a more specialized use of primarily short range defense and the user preferred a MG pack that could be used in any tactical situation, even if at shorter ranges it was not as effective. The Infantry board also cited the M198 with a “short-coming” because of the rounds poor penetration ability versus the standard M80 ball.

FRANK HACKLEY WAS THE LAST COMMANDER OF FRANKFORD ARSENAL and Co-Author of " History of US small arms ammunition", Hackley, Woodin and Scranton - which everyone should own.


#9

Here’s a picture of a M198 Duplex I’ve done (along with some other oddballs); 9th and 10th from the right in the top row. The projectiles are copper-plated steel, and the base of the bottom projectile is canted so that it’s designed to hit within a 12" circle of the top projectile at 100 yards. They ALSO made a “low-recoil” round loaded only with the TOP projectile, marked with a white tip.


#10

SDC, please could you post a list of what all those rounds are? Am i right in thinking that 3 and 4 are .303s? Also, what is that grey rectangular plastic box on the top left?


#11

Some real nice cuts. How did that Israeli teargas 7.9 work out ?

.


#12

Thanks. (And yes, it WAS definitely tear-gas :-) )


#13

Sure; from L-R, T-B are: An old-style electrically-initiated Taser cartridge (the newer ones are CO2-propelled, but this one uses an internal charge of priming compound), a 7.92 Mauser B-Patrone spotter, a 7.7x56R/.303 Brit Italian-manufactured API with a WP incendiary charge in a foil envelope above the core, a 7.65 Arg Mauser explosive round (same fuzing system as the B-Patrone), a 7.92 Mauser Israeli-made tear-gas round, a 7.62 NATO M198 Duplex, a 9mm SMAW spotting round, a 308 Win Karlyn rifle flare, a 5.6x57mm SPIW flechette cartridge, a 5.56mm NATO flechette for the ACR programme, (bottom row) an FN 5.7x28mm PDW round, a 38 Spl “Shortstop” sky-marshall round, a 9mm Para Men-D copper-capped hollowpoint, a 9mm Para Flateau-designed semi-AP JHP, and a 9mm Para THV by SFM in Fance.


#14

SDC- You might want to talk to Paul Smith to see how he does the powder charges.
I would like to invite you to submit some of your favorites as “Cartridge of the Month” submissions along with a paragraph or two of history or pointing out what makes them interesting. PM me for address.


#15

How do you section an incendiary or explosive round safely? This is NOT something I want instructions how to do because I want to try. A: Because I have no explosive or incendiary rounds, and B: Because I want to keep a full set of fingers and eyes. I am just curious how it is done.

WARNING- Sectioning of cartridges or removing bullets may result in death or serious bodily injury if not done with extreme caution, by people who are well aware of the exact nature of the round they are working on, and using appropriate safety measures. Leave this sort of work to experts. Due to liability concerns, IAA will not allow discussion of the methods used on this forum. Admire the results, and learn from them, but we caution everyone NOT to attempt this on their own.

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#16

[quote=“John S.”]SDC- You might want to talk to Paul Smith to see how he does the powder charges.
I would like to invite you to submit some of your favorites as “Cartridge of the Month” submissions along with a paragraph or two of history or pointing out what makes them interesting. PM me for address.[/quote]

Thanks; I’ve met Paul (and his father) a couple of times, and he does some amazing work. I’ve tried to mount the powder charges in wax before, but it never “looked right” to me, so I gave it up as an exercise in futility. Right now, I’ve got 2 briefcases full of assorted cutaways, and I’m always looking out for more examples that would make interesting sectioned rounds.


#17

{** Technical discussion removed per site policy in such matters (copied following)** . . . this was not established until after this post was made and is not a reflection, in any way, on this individual - Iconoclast}

WARNING- Sectioning of cartridges or removing bullets may result in death or serious bodily injury if not done with extreme caution, by people who are well aware of the exact nature of the round they are working on, and using appropriate safety measures. Leave this sort of work to experts. Due to liability concerns, IAA will not allow discussion of the methods used on this forum. Admire the results, and learn from them, but we caution everyone NOT to attempt this on their own.

.

Here’s a close-up shot showing that .303 British API you asked about earlier; L-R are 2 different .303 BIV incendiaries (the one on the right is a smoke tracer, with a bleed hole for the WP smoke at the side of the projectile), the Italian API, and a 7.62x54R API with incendiary compound at both the nose and rear of the projectile.


#18

Interesting pics. You can see those .303 British somke tracers in action on some original Battle of Britain gun camera film I have in a video on the development of the Spitfire. How do you prevent WP from ignitng once it is taken out of the water? My understanding is that is ignites on contact with air. Is this correct?

WARNING- Sectioning of cartridges or removing bullets may result in death or serious bodily injury if not done with extreme caution, by people who are well aware of the exact nature of the round they are working on, and using appropriate safety measures. Leave this sort of work to experts. Due to liability concerns, IAA will not allow discussion of the methods used on this forum. Admire the results, and learn from them, but we caution everyone NOT to attempt this on their own.

.


#19

{** Technical discussion removed per site policy in such matters (copied following)** . . . this was not established until after this post was made and is not a reflection, in any way, on this individual - Iconoclast}

WARNING- Sectioning of cartridges or removing bullets may result in death or serious bodily injury if not done with extreme caution, by people who are well aware of the exact nature of the round they are working on, and using appropriate safety measures. Leave this sort of work to experts. Due to liability concerns, IAA will not allow discussion of the methods used on this forum. Admire the results, and learn from them, but we caution everyone NOT to attempt this on their own.

.


#20

How about a closer look at some of your bigger items?