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Old June 25, 2016, 12:54 AM   #1
TXAZ
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Why not Tungsten match rounds for 70% greater ballistic coefficient?

I understand it is difficult to machine, but with a 70% greater density than Lead, and assuming you could machine the exact same size match sized ammo, why wouldn't competition shooters go for the much higher Ballistic Coefficient of a tungsten round when cost for some of the large bore match ammo can be $5-15 per round for .50 BMG for instance.

I'm sure there's a reason for it but I couldn't find it.
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Old June 25, 2016, 01:06 AM   #2
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That would be a "AP" round , not to mention the cost those would be . I know my tungsten darts cost a couple bills . There might be a very small market for something like that though .
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Old June 25, 2016, 01:14 AM   #3
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Instead of a 750 gr 50 cal bullet you'd have a 1250 gr 50 cal bullet. What velocity could you get with that?
Don't know how much difference there would be in BC.
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Old June 25, 2016, 03:21 AM   #4
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Tungsten carbide penetrators are available in the military market. They aren't exactly totally awesome sauce in terms of terminal effects. The Raufoss M211 is a good round, but honestly the penetrator there is a bit of an afterthought, more designed to kill engine blocks than anything else, which is something that normal 50 cal ball can do quite nicely.

Remember Energy = 1/2 Mass times Velocity squared, so increasing mass is less effective at energy generation than increasing velocity. Force = Mass times Acceleration, so a given mass will have more force for any given acceleration (such as impact which is a negative acceleration of velocity). However, tungsten doesn't deform well, it either holds together and makes a nice hole, or if it hits something hard enough will shatter.

So this is the reason that no one makes pure tungsten bullets, or even uses tungsten penetrators in the bulk of their 50 caliber bullets, and saves the Tungsten for the Armor Penetrating Fin Stabilized Discarding Sabot main tank gun rounds.

Here's a NAMMO brochure with good pics: http://www.dtic.mil/ndia/2015smallar...79_Erninge.pdf

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Old June 25, 2016, 06:46 AM   #5
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The melting point of tungsten would make it difficult to deal with. At roughly 6200 degrees fahrenheit it would melt nearly any mould you'd be pouring it into (short of ceramic). Not sure if forging would work or just beat up the tooling either. Also, as others have pointed out, trading the density for velocity is a losing proposition.
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Old June 25, 2016, 07:40 AM   #6
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I was sure there was a reason, thanks gentlemen!
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Old June 25, 2016, 07:54 AM   #7
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You could get tungsten rod and shape them into bullets. Would be pretty hard on the rifling though.

In any case weight is not the only factor in calculating BC shape is important (why bullets of the same weight have different BC's). What would your example be to reach a 70% gain in BC?

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Old June 25, 2016, 07:55 AM   #8
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It's also absurdly hard, I believe. BHN of bazillions

So I imagine that would slash the life-span of the rifling unless a copper jacket were made thick enough to absorb the rifling cut entirely. Even then, the bore would surely suffer far heavier wear.
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Old June 25, 2016, 08:18 AM   #9
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Quote:
why wouldn't competition shooters go for the much higher Ballistic Coefficient of a tungsten round
I do not know; but, I find nothing exciting about chambering a round in a rifle with a projectile that is too hard to imprint to the rifling. I can only imagine the amount of pressure required to force the projectile down the bore.

There is always insulators like a sabot.

http://www.sabotreloadingpro.com/

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Old June 25, 2016, 08:38 AM   #10
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While tungsten is impractical, if you can afford it gold would make you a decent bullet with 50% higher sectional density. So you probably want to use your own gun range with a bullet recovery backdrop, at $250 per 100 gr .22 the price is steep, even for a benchrester.
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Old June 25, 2016, 10:31 AM   #11
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Two points, for the first part, it might invoke intervention from atf. Tungsten handgun bullets of any sort, if I understand, are illegal for use by civilians, as well as several other other types.

Now, for the important part. adding tungsten to any bullet and retaining the same weight Will shred your bc, not improve it. Consider this. Take a 158 gran semi wadcutter and consider how scrappy the bc is. Then consider a 150 grain spitzer in .308. Enormously increased bc. Then think about a good vld match/ long range bullet. Maybe solid copper so it can be lighter, and stretched out even longer. Or put in a lightweight polymer tip and a lightweight hollow cavity under the tip.

Sectional density only considers the weight and diameter. No matter how it is shaped, a 150 grain.308 bullet would have the same sd. The bc is dependent on both the bc and shape. Stretch it out, make it more aerodynamic, even change the material so that it's even more streamlined, and yo will increase that bc even more.

Go to Sierra website and study the information on .308 bullets, for example, and the bc numbers.

The most common means of measurement, if I'm not mistaken, is to fire a bullet, and measure velocity at muzzle and a number of distances. By finding the velocity charges, the mathematically work backwards to get bc.

So no, adding tungsten, or or any denser material will do nothing but make your bullet a bit stubbies and lower your bc.
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Old June 25, 2016, 11:05 AM   #12
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Speer made a solid hunting bullet with a tungsten alloy core 20 years ago. Barnes used to make a copper bullet with a tungsten alloy insert.
The military bullets are jacketed tungsten carbide. Or at least some of them are, or were. Denser than lead, not as dense as tungsten.
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Old June 25, 2016, 12:10 PM   #13
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Per above, you don't' have to have all tungsten, just a core and right location and balance and build a bullet structure around it.

They put copper over lead, more complicated obviously but not undoable.

On the other hand, it sure would cost.

Key is it does not have to have anything to do with penetration (AP).

Me, I am waiting for the depleted uranium round!
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Old June 25, 2016, 12:27 PM   #14
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Tungsten is too light, expensive and brittle. Hard to work too. Isn't the same thing as tungsten carbide either.
Military bullets are jacketed with copper or mild steel. WC is way too hard for bullet jackets.
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Old June 25, 2016, 01:03 PM   #15
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Tungsten is too light
Light?!

It has a density of 19.25gr per cm3, to lead's 11.34gr!
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Old June 25, 2016, 03:19 PM   #16
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Tungsten is too light, expensive and brittle. Hard to work too. Isn't the same thing as tungsten carbide either.
Military bullets are jacketed with copper or mild steel. WC is way too hard for bullet jackets.

Light? Hmmm

And it does not have to be jacketed or anything.

You make a core of tungsten that replaced the lead (less), it just has to balance the bullet right for the job.

I am not saying its remotely worth it but it can be done.

And I still thing depleted uranium is the way to go.

For game use there is no residue and you can scatter that previously nasty stuff around and let it go back to nature.
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Old June 25, 2016, 06:32 PM   #17
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Tungsten and DU are nasty things to work with, and have no real usefulness outside of destroying armored vehicles. Certainly the copper and lead hunting bullets we have available cover down on all our hunting needs so far, so until something new comes along that is armor plated, no need for tungsten.

As far as an increase in BC goes, sectional density has to do with the frontal area of the bullet and the total mass of the bullet. You'll get a higher BC from a less dense bullet over a more dense bullet for the same mass, for example going from the Copper/Steel/Lead M855 to the Copper/Steel M855A1 we gained a little BC because even though the sectional density was the same, the less dense M855A1 is longer with a better boat tail and more consistent bullet base.

The time to increase the projectile mass is when you can't reasonably increase the velocity any more, such as for 20mm and larger Cannons and Tank rounds. The effect of putting tungsten penetrators in small arms bullets is really context specific. Small arms are generally for shooting at people, so an armor piercing 5.56 bullet isn't going to give you any better terminal performance than an Mk318 bullet, through normal barriers (car windshields, doors, etc).

As far as any potential increases in accuracy, the most accurate bullets are match bullets with a reverse drawn jacket and uniform lead core, this is mostly because these bullets are the easiest to make uniform for imbalance and for uniformity of external dimensions. The old Garand shooters did like AP ammo for matches because the 160 some odd grain bullets did have a better BC than the 150gr M2 ball ammo, but some AP ammo was constructed with poor bullet imbalance and so you'll find a lot of differing opinions on the matter.

So generally, less dense and longer is better for ballistics because you can get a higher BC bullet at a higher velocity (within the realm of Copper, Steel, and Lead).

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Old June 26, 2016, 12:33 AM   #18
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Yes, Speer did make a tungsten cored rifle bulle5, the grand slam safari. The thing had a big, heavy tungsten core that was probably sintered to shape, and in sure that it wasn't swaged like typical lead. That extra heavy jacket appeared to essentially be folded over the base, so the somewhat brittle core wasn't stressed by intense pressure of swaying.

They were about 20%shorter than lead solids, and allowed a few more grains of powder with the same goal.

People didn't buy them. The monolithic bronze bullets won the market. The bronze solids were turned and needed no carting around with a core. Much cheaper to make, probably.
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Old June 26, 2016, 08:28 AM   #19
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Why not gold or DU?
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Old June 26, 2016, 12:38 PM   #20
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DU has been brought up in two posts above by yours truly as well as answered by Jimro.

I like the gold idea though. For billionaires and jet setting exclusive hunting camp (luxury inn) Supreme Court Justices.
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Old June 26, 2016, 04:01 PM   #21
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Corbin sold Tungsten powder for bullet cores for a long time, but I see they say it is now discontinued due to high market prices. When Precision Shooting was still publishing, someone was making Tungsten core bullets and published some positive things about what they could make them do, but I don't think they ever took off. The idea was, as suggested earlier, you could have more powder space for your bullet weight. The idea was extra velocity and the extra mass would make up for the shorter shape if you did the shorter shape right. The extra mass and shorter shape would let you use a slower rifling pitch as the greater mass doesn't need to spin as fast to achieve stability. This lets you drive it still faster without disintegrating from spin and it then tends to have less wobble in flight.

Too expensive, at several dollars a bullet.
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Old Yesterday, 08:46 AM   #22
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Im amazed at the price of tungsten these days. Almost ten bucks to purchas scrap, and scrap isn't going to b the price of useable powder, that should run almost twice that price, and any machined materials of any sort will probably run at least $100 a pound, whether it's rod, or any simple bulk product.

I remember reading up on the price of carbide scrap years ago and it wasn't even half of that price. There must have been some political change in the price, it is mined in south america and russia, IIRC. I do know that machine shops have never dumped their carbide tools, and they will pop the inserts off of their saw blades if there are many blades worn out. It doesn't take a whole lot of carbide equipment or tools to reach a pound.

a cubic inch of tungsten weighs almost a half pound. That's even denser than my brother in law.
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Old Yesterday, 09:41 AM   #23
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It's funny. You'd think with the incandescent light bulb dying out, there would be less demand for tungsten, not more. Perhaps it is tooling demand coupled with the tungsten carbide wedding ring fashion that has taken the trend the other way?
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Old Yesterday, 09:47 AM   #24
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Quote:
Corbin sold Tungsten powder for bullet cores for a long time
I remember that, for a while there it was touted as "The next big thing®" for Service Rifle shooters using the AR15, because the Tungsten cores you could get close to the BCs of the 80 grain Sierra Matchking and JLK VLD bullets but load them to fit in a standard AR magazine.

I don't remember why they fizzled out, pretty sure cost was a big part of it, at the time you could use LRP magazines and load 80 grain SMKs plenty long for most rifles. If you shot a lot, the cost would swing in favor of LRP magazines and conventional lead bullets pretty quickly.

Because the core was compressed powder, ATF didn't care, they were much closer to frangible than armor piercing.
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Old Yesterday, 09:55 AM   #25
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Looking at these photos of the Speer African grand slam bullets.

http://www.armslist.com/posts/362067...-core-500gr-25

Looks like they just have a cylinder of tungsten installed from the bottom, maybe not unlike like installing something into a HP, plastic tipped bullets.

The easiest way, if you already have a hollow base bullet, to make them would be to use tungsten TIG welding electrodes. Talk to an old welder that doesn't ever throw anything away, as even if they are too short to fit in the torch any longer, they would still be long enough to make a core.

Most of mine are the 2% thoriated style that the Danish welding institute wants to phase out because they are radioactive but I have lots of pure tungsten too.



you can get them up to 1/4" diameter. It can be worked easy as long as your using an abrasive method. I sharpen them to a point with a regular sanding belt/disk all the time.
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