# Exotic Ammo: Tungsten Carbide



## Darb

Over in the Optimum Projectile Size thread of ZDP-189's excellent blog, Dan and Aaron had both mentioned being intrigued on past occasions with the unique properties of high-density Tungsten as a possible slingshot ammo, but that it's being "fabulously expensive" rendered it impractical. I was immediately curious, and began doing a little research, and because said research was becoming a bit too off-topic to a blog thread about optimal shot sizing, I've opted to repost the info here in the main forum, where more people can see it and get involved.

*Advantages of Tungsten-Carbide Shot:
*
*a) Density:*

Hunters are well acquainted with the advantage of lead (11.3 gr/ccm density) over steel (7.8 gr/ccm) - with a 45% greater density, it's significantly smaller for the same mass, which translates into greater penetrating power and less aerodynamic drag. As it turns out, depending on how much (and in what) Tungsten-carbide powder (or simply "Carbide") is cemented or "matrixed" (usually in iron-nickel or cobalt), it has roughly the same mass advantage over lead as lead has over steel: at 14-18.5 gr/ccm density, some formulations are almost as dense as pure gold (19 gr/ccm). That sheer density makes the material VERY interesting from a ballistics standpoint ... in fact, if you run the numbers, a 3/8" ball of the stuff (roughly 36 cal or 9.5mm, which is comparable to "0000 Buckshot") can have roughly the same mass as .44 cal lead and 50 cal steel.

*b} Hardness:*

Tungsten Carbide is TOUGH stuff ... it's used on the tips of saw blades, for drill-bits, for shot-blasting the rust off of steel-plate, and the military uses it in high-velocity armor penetrators in certain anti-tank rounds, and also as the munition of choice in anti-personnel fragmentation munitions.

*c) Non-Toxicity:
*
Unlike lead, which is a toxic heavy metal, carbide is relatively non-toxic.

*d) Corrosion Resistance:*

Carbide is naturally stable because the tungsten is already in a highly stable molecular bond with carbon, and is therefore resistant to corrosion in most ambient temperature conditions.

*e) High Melting Point:*

Tungsten has a very high melting point &#8230; so high, it was/is the chief ingredient in the filaments used in incandescent light bulbs.

Ok, so far, the stuff looks like a dream-material, from a munitions standpoint ... it's super-dense, extremely hard, corrosion resistant, and non-toxic. So why isn't everyone using it ? Therein lies the catch.

*Disadvantages of Tungsten-Carbide:* 
(as a re-usable slingshot munition)

*a) Expense:
*
Expense, expense, expense. This seems to be the biggie. First of all, this element is not as abundant as iron or lead, and it's very hardness and extremely high melting point make it difficult and energy intensive to work with &#8230; hence the expense. The chief use I've seen for most carbide balls seen on the internet are for super-hard long-life precision bearings in industry (and also for the tips of ballpoint pens), and they're expensive. There are small companies out there that have tried to market tungsten pellets as a non-toxic alternative to birdshot, but they've run afoul (pun intended) of the same price hurdle &#8230; hunters, even those who try to save money by loading their own rounds, don't want to pay upwards of $2-3 extra per shotgun shell, just to fire tungsten instead of lead or steel. It's even harder to find 0000 buckshot for deer.

*b} Magnetism:*

This is a relatively minor issue, compared to expense, but whether or not shot can be picked up with a magnet is either a yawner or a deal-breaker to some people, depending on the circumstances. For someone like me, who routinely reuses ammo, magnetically recoverable ammo is a big factor in determining whether or not something is cost effective. Tungsten-carbide by itself is non-magnetic. HOWEVER, most matrix formulations contain varying amounts of iron and/or cobalt &#8230; the more matrix, the more magnetic it tends to be. The drawback is that the more matrix is present, the lower the density falls in that highly attractive (pun intended) 14-18.5 gr/ccm range. In general, just looking at the chemistry, it's probably a safe bet that most carbide shot is going to be either weakly or moderately magnetic, if it lists at least 5-10% iron and/or cobalt as it's matrix.

*Bottom Line:* I'm assembling some cost data from several suppliers, with an eye towards unpolished 9.5mm size shot. Most of the sources I've found thus far are in China and India, but I found a source in California that's offering 9.5mm carbide balls for $38/lb, plus S&H, with a 1 pound minimum order, which seems like a viable source for a small test buy. I have several other potential; sources I haven't heard from yet.

The only way to know for sure how well suited this is for slingshotting is for me to get a small quantity, and shoot with it in my backstop/recovery setup. I'll post any progress I make to this thread.

Anyone else have any experience or data to offer ?

EDIT: to correct a mysterious posting error bug, I've had to strip out all formatting and hyperlinks from this post, which I'll try to restore as time permits.


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## Darb

Ack ... kinda frustrating when forums auto-format a 'b'+')' into a







. It makes alphabetized lists looks silly, and for some reason I cant seem to edit the above post in this thread (potential bug). I usually set the auto-censor to auto replace it with 'b}' on my sites. Oh well.

Meanwhile, more data will be forthcoming, including a shot size/mass table, pricing, etc.

EDIT: Aaron - I sent you a debugging image. Please feel free to split this post over into the appropriate debugging area, if one exists.

EDIT2: I bypassed the bug by eliminating all special formatting and reposting ... now I can finesse it to restore the missing hyperlinks and fix the misalignments.


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## NightKnight

Great post! If you search the forum for Carbide, you can see I was very interesting is sourcing the stuff. I hit some dead-ends, but I would still love to buy it!


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## Darb

Preliminary price data:

* Birdshot #5: Here's an outfit that sells tungsten birdshot #5 (too small for slingshot) at $24/lb. This formulation appears to be straight carbide, without cobalt, so it'd be non magnetic. {https://www.tungsten...6&code=TSS_SINK}

* BB & BBB sized shot: This outfit sells those sizes for just over $32/lb if you go for a 6lb min. That's steep, but if you're big into airguns, and cost is no concern, it might make for an interesting experiment to share with a few of your airgun friends: {http://www.tungsten-...gsten_shot.html}

* BALLS: The same outfit also sells larger size ball/pellets: 7.87mm, 8.2mm, 9.5mm and 12.7mm for $38/lb ($96/kg) plus shipping and handling {http://www.tungsten-.../inventory.html}. That's roughly 70 cents a shot for 9.5mm (3/8") or 35x the price of Royal Steel Ball's chromium slingshot ammo (2 cents each) and 2x the price of 4xx series stainless steel. If you have an effective backstop that captures virtually all of your ammo, then their one pound minimum order (roughly 50 shots of 9.5mm) becomes feasible to consider playing with. Their particular formulation appears to be maximum density 18.5 gr/cm**3, which is even closer to gold's density than the cobalt-matrix formulations I was referring to earlier, but accordingly it's probably low or non-magnetic. I have to admit, it'd be very cool to play with some 3/8" shot that has even greater range and penetrating power than .44 cal lead, and with the same mass as 50 cal steel.

I already have a call into that latter outfit, for samples ... people might want to hold off on calling in on their own until I have a chance to evaluate the stuff.

I also have a few queries with some other outfits I haven't listed yet.

WARNING/DISCLAIMER: Warning - although 9.5mm (3/8") is roughly the same size as 'quad-naught' (0000) Buckshot, I don't recommend putting the stuff in a shotgun shell without careful research, because it's so dense that the resulting compression could explode your barrel. Check your manufacturer's specs carefully before considering it. Ditto for people with airguns considering tungsten BB's ... check with your manufacturer. I can accept no responsibility for anyone but myself when it comes to playing with this stuff, so be sure to do your homework.


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## Darb

Here's a quick comparison of a typical tungsten-carbide formulation, and how it compares to steel, lead and gold. This particular data is for a carbide-cobalt alloy #W273 (15% cobalt, rendering it slightly magnetic and electrically conductive).

Density:
Steel = 7.8 gr/ccm
Lead = 11.3 gr/ccm (+45%)
W273 carbide = 17 gr/ccm (+118%) 
Gold = 19 gr/cm (+143%)

Ammo Mass, grams (Steel/Lead/W273):
1/4" = 1.05/1.52/2.28
3/8" = 3.46/5.34/7.555
7/16" = 5.6/9/12.21
1/2" = 8.37/12/18.23

Pretty dense stuff.


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## Darb

ANOTHER WARNING (for gun users): because the carbide is probably harder than the material forming the barrel of your shotgun or airgun, use of carbide shot could, potentially, cause excessive wear, or scoring, of the inside of your barrel. Another reason to do any requisite specs homework before considering the use of this stuff.

I'm just looking at it from a slingshot perspective.


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## Rayshot

Darb said:


> ANOTHER WARNING (for gun users): because the carbide is probably harder than the material forming the barrel of your shotgun or airgun, use of carbide shot could, potentially, cause excessive wear, or scoring, of the inside of your barrel. Another reason to do any requisite specs homework before considering the use of this stuff.
> 
> I'm just looking at it from a slingshot perspective.


I would also like to buy some. I will wait for the responses.

Thanks for the information, Darb.


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## Darb

Here are the sphere masses for tungsten alloy with a slightly higher density of 18.5:

Ammo Mass, gr (Steel/Lead/Tungsten):
1/4" = 1.05/1.52/2.48gr
3/8" = 3.46/5.34/8.22gr
7/16" = 5.6/9/13.28gr
1/2" = 8.37/12/19.83gr


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## Darb

I'm bored and nothing is on TV, so it's time for a little light mathematical offroading.

I was considering impact force concentration just now ... just bear with me for a bit. Using basic geometric equations, I derived values for volume and hemispherical surface area (HSA) for the 3 most common standard size slingshot ammo already mentioned:

3/8" shot: Volume = 0.02712 CI, HSA = 0.22089 SqIn
7/16" shot, Volume = 0.043846 CI, HSA = 0.30066 SqIn
1/2" shot, Volume = 0.06545 CI, HSA = 0.392698 SqIn

Given that 3/8" tungsten, 7/16" lead and 1/2" steel are roughly the same mass, and if we then stipulate a situation in which all three shots are moving in parallel trajectories with the same approximate kinetic energy, we can then use their difference in HSA to approximate their difference in their ability to concentrate their impact force ... the latter would be approximately the inverse of the other (i.e., if A is half the size of B, it should have roughly twice the impact force concentration for the same kinetic energy). Thus:

* 3/8" tungsten has 73.37% of the hemispherical surface area of 7/16" lead, and therefore 36.3% greater impact force concentration. It has 56.25% of the HSA of 1/2" steel, and therefore 77.78% greater impact force concentration.

* The same approximate numbers probably hold true for comparing 7/16" tungsten to 1/2" lead to 9/16" steel.


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## Tex-Shooter

As a practical application, If looking only at the penetration, the 3/8 carbide is superior. The 3/8 carbide at long distances has a flatter trajectory and carries better because of the smaller size. But if delivering total energy to small game, the 7/16 lead is superior. It has sufficient penetration plus because of its softness, it does not tend to ricochet off and therefore delivers more dead blow and energy with most shots. The 1/2 steel is easier on a catch matt, therefore better suited for target shooting. At common slingshot shooting distances it is very hard to tell the difference in trajectory even though there is a little. Also the carbide is dog-gone expensive. -- Tex-Shooter


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## Darb

Ah, some sagely direct experience from a true pro ... always better than mere theory and speculation. Thanks, Bill.









The tendency of hard shot to ricochet off hard bone at midrange and beyond hadn't occured to me ... but I think the non-toxicity advantage of carbide might help to mitigate that consideration for some.

Also (and this is just theory, not practical experience talking), if someone's shooting at something with bones strong enough to potentially deflect carbide, they should probably be using a gun or bow anyway ... for example, unless someone's an ace shooter who can reliably score head shots from med-range, I wouldn't recommend attempting a turkey with a slingshot, regardless of how strong your bands what ammo is used (turkey's, like squirrels, are very resilient for their size). I'd guess even canadian geese would probably be too big for slingshooting, unless someone's an ace head-shooter.

As for targets, I completely agree ... carbide is too expensive to use anywhere except in a backstop that allows reliable recovery and reuse. Stumpshooting, for example, would be a total waste of money.


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## Tex-Shooter

I have found that it is not just bone that defects hard shot such as carbide and steel! I have noticed that if hard shot is not close to the center of a targeted animal a lot of times it seems to slide off the hair rather than penetrate, but lead shot does not do this near as bad. I also have noticed that when hunting in a rocky area, hard shot will sometimes bounce right back at you. This is especially dangerous if hunting pigeons under a bridge. I don't recommend this anyway as it is illegal in some areas, but I know that it is being done. – Tex-Shooter


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## Performance Catapults

Darb said:


> ...unless someone's an ace shooter who can reliably score head shots from med-range, I wouldn't recommend attempting a turkey with a slingshot, regardless of how strong your bands what ammo is used...


If attempting a turkey, squirrel or rabbit, a head shot is the *only* option.


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## Darb

BTW, the high price of gold has apparently stimulated the use of Tungsten Carbide as a material for wedding rings. The selling point is that carbide, which is similar in weight to gold, is far harder ... the 2nd hardest substance behind diamond on the Mohs scale.

http://www.amazon.co...ref=pd_sim_jw_1


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## Brooklyn00003

Performance Catapults said:


> ...unless someone's an ace shooter who can reliably score head shots from med-range, I wouldn't recommend attempting a turkey with a slingshot, regardless of how strong your bands what ammo is used...


If attempting a turkey, squirrel or rabbit, a head shot is the *only* option.
[/quote]

And chicken !!!


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## Darb

I normally hunt for chicken with carefully folded paper money, rather than a slingshot ... but that's just me.


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## Brooklyn00003

Darb said:


> I normally hunt for chicken with carefully folded paper money, rather than a slingshot ... but that's just me.


NORMALLY I do it the same way too


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## Darb

^bump^

Just giving this thread a bump. I'm planning on placing an order for 1 lb of 3/8" tungsten sometime early next week. I was going to do it this week, but life has been ... busy ... and expensive, of late.


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## NoSugarRob

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## Darb

You lost me, my friend ... I don't own a Tungsten ring. Mine's 14k gold.

I was just pointing out a recent trend in an alternate use of Tungsten.


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## ZDP-189

I have a tungsten ring almost identical to my wedding ring that I wear for black tie occasions and when on holiday in less salubrious locations. The idea is it looks great and I don't mind having it lifted. 
A real wedding ring should should be 9-18K gold. 24K is too soft. 9-18K is hard enough and easy to stretch or bridge if you gain weight. 9K white gold will pass for slightly tarnished silver and is less showy. Platinum also works if you have the budget.


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## NoSugarRob

?


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## Darb

Ok, I got it. And no, I dont have a tungsten carbide ring serving as a turdcutter. C3P0 perhaps, but not me.









We should probably get back on topic before the thread police lock us up.


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## Darb

Ok, I'm going to order a pound of the 9.5mm for experimentation.

Here are the numbers I derived for the 4 most useful sizes (from a slingshot standpoint) of carbide shot the outfit** sells:

Metric Diam >> English Diam >> Mass for 17.5 density Tungsten (Grams) >> Joules at 200 fps:

7.87mm >> 0.3098in >> 4.46 grams >> 8.3j
8.2mm >> 0.3228in >> 5.05 grams >> 9.39j
9.5mm >> 0.374in >> 7.85 grams >> 14.6j
12.7mm >> 0.5in >> 18.77 grams >> 34.89j

Approximate Mass equivalents:

9.5mm (3/8") Carbide = 12.7mm (1/2") Steel = 11.2mm (approx .44cal or 7/16) Lead

------------------------
**Company: Tungsten Spheres, San Diego California.
Price: $38/lb, 1lb min


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## Darb

When they arrive, I'll be shooting them with EPS-017 using Tex-Shooter's Express Bands, which according to Jim Harris are reliably able to shoot 1/2" steel at 190-200 fps. Since 1/2" steel is roughly the same mass as the 9.5mm tungsten I'm ordering, the 14.6 joules figure I roughed out above should be fairly close.

It'll be interesting to see if I can put a 9.5mm carbide shot through 2 coconuts, back to back. At the very least, it'll give the 2nd nut a really nasty headache.


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## Darb

Darb said:


> Company: Tungsten Spheres, San Diego California.
> Price: $38/lb, 1lb min


Scratch that outfit ... they recently changed their website inventory prices to say "price is per pound" (it previously read "Price is EACH, not per pound", and last time I called I was told it was for kilos).


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## Darb

Trying Salem Specialty Ball next ...

All their stuff is highly polished grade 25 and their density is running around 15.1. I've got someone checking if they can sell banded slugs in the 3/8" - 10mm range that havent even been heat treated or ground, much less polished ... that might drop the price into a manageable range.


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## Brewman

This is pure gold!!!!!!!!!


Darb said:


> Over in the Optimum Projectile Size thread of ZDP-189's excellent blog, Dan and Aaron had both mentioned being intrigued on past occasions with the unique properties of high-density Tungsten as a possible slingshot ammo, but that it's being "fabulously expensive" rendered it impractical. I was immediately curious, and began doing a little research, and because said research was becoming a bit too off-topic to a blog thread about optimal shot sizing, I've opted to repost the info here in the main forum, where more people can see it and get involved.
> 
> *Advantages of Tungsten-Carbide Shot:
> *
> *a) Density:*
> 
> Hunters are well acquainted with the advantage of lead (11.3 gr/ccm density) over steel (7.8 gr/ccm) - with a 45% greater density, it's significantly smaller for the same mass, which translates into greater penetrating power and less aerodynamic drag. As it turns out, depending on how much (and in what) Tungsten-carbide powder (or simply "Carbide") is cemented or "matrixed" (usually in iron-nickel or cobalt), it has roughly the same mass advantage over lead as lead has over steel: at 14-18.5 gr/ccm density, some formulations are almost as dense as pure gold (19 gr/ccm). That sheer density makes the material VERY interesting from a ballistics standpoint ... in fact, if you run the numbers, a 3/8" ball of the stuff (roughly 36 cal or 9.5mm, which is comparable to "0000 Buckshot") can have roughly the same mass as .44 cal lead and 50 cal steel.
> 
> *b} Hardness:*
> 
> Tungsten Carbide is TOUGH stuff ... it's used on the tips of saw blades, for drill-bits, for shot-blasting the rust off of steel-plate, and the military uses it in high-velocity armor penetrators in certain anti-tank rounds, and also as the munition of choice in anti-personnel fragmentation munitions.
> 
> *c) Non-Toxicity:
> *
> Unlike lead, which is a toxic heavy metal, carbide is relatively non-toxic.
> 
> *d) Corrosion Resistance:*
> 
> Carbide is naturally stable because the tungsten is already in a highly stable molecular bond with carbon, and is therefore resistant to corrosion in most ambient temperature conditions.
> 
> *e) High Melting Point:*
> 
> Tungsten has a very high melting point &#8230; so high, it was/is the chief ingredient in the filaments used in incandescent light bulbs.
> 
> Ok, so far, the stuff looks like a dream-material, from a munitions standpoint ... it's super-dense, extremely hard, corrosion resistant, and non-toxic. So why isn't everyone using it ? Therein lies the catch.
> 
> *Disadvantages of Tungsten-Carbide:*
> (as a re-usable slingshot munition)
> 
> *a) Expense:
> *
> Expense, expense, expense. This seems to be the biggie. First of all, this element is not as abundant as iron or lead, and it's very hardness and extremely high melting point make it difficult and energy intensive to work with &#8230; hence the expense. The chief use I've seen for most carbide balls seen on the internet are for super-hard long-life precision bearings in industry (and also for the tips of ballpoint pens), and they're expensive. There are small companies out there that have tried to market tungsten pellets as a non-toxic alternative to birdshot, but they've run afoul (pun intended) of the same price hurdle &#8230; hunters, even those who try to save money by loading their own rounds, don't want to pay upwards of $2-3 extra per shotgun shell, just to fire tungsten instead of lead or steel. It's even harder to find 0000 buckshot for deer.
> 
> *b} Magnetism:*
> 
> This is a relatively minor issue, compared to expense, but whether or not shot can be picked up with a magnet is either a yawner or a deal-breaker to some people, depending on the circumstances. For someone like me, who routinely reuses ammo, magnetically recoverable ammo is a big factor in determining whether or not something is cost effective. Tungsten-carbide by itself is non-magnetic. HOWEVER, most matrix formulations contain varying amounts of iron and/or cobalt &#8230; the more matrix, the more magnetic it tends to be. The drawback is that the more matrix is present, the lower the density falls in that highly attractive (pun intended) 14-18.5 gr/ccm range. In general, just looking at the chemistry, it's probably a safe bet that most carbide shot is going to be either weakly or moderately magnetic, if it lists at least 5-10% iron and/or cobalt as it's matrix.
> 
> *Bottom Line:* I'm assembling some cost data from several suppliers, with an eye towards unpolished 9.5mm size shot. Most of the sources I've found thus far are in China and India, but I found a source in California that's offering 9.5mm carbide balls for $38/lb, plus S&H, with a 1 pound minimum order, which seems like a viable source for a small test buy. I have several other potential; sources I haven't heard from yet.
> 
> The only way to know for sure how well suited this is for slingshotting is for me to get a small quantity, and shoot with it in my backstop/recovery setup. I'll post any progress I make to this thread.
> 
> Anyone else have any experience or data to offer ?
> 
> EDIT: to correct a mysterious posting error bug, I've had to strip out all formatting and hyperlinks from this post, which I'll try to restore as time permits.


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## Darb

Thanks, Brewman.

I need to followup with Salem Ball, but I've had out of town relatives visiting, as well as plumbing and PC issues for the past few days that all took priority.

Also, the person I was speaking to at Salem Ball sounds (so far) like an absent-minded ninny who could barely remember things from once sentence to the next. Not very encouraging. I'll try one last time with Mr. Dullard (real name witheld), and if I strike out I'll move on to another source.

As of this writing, this whole endeavor seems rather iffy. I can appreciate why Aaron and Danny gave up previously.


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## Tom Krein

One word of caution on titanium and carbide tungsten rings.... IF you have a finger injury remove your ring immediately, prior to the swelling! Most ER departments will not be able to cut titanium or carbide rings off!!

Tom


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## Darb

Excellent advice, Tom. Aside from the fact that I'm already wearing gold, I'd never wear a carbide ring for that very reason.

Meanwhile, I'll give Salem Ball another call, once the plumbers here are done (home repairs).


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## ZDP-189

Tungsten ring stuck on your finger? I'll get it off with my plasma cutter. If you are squeemish, a cleaver would be less messy.









Tungsten spheres has indeed been wierd. I wrote them off when they quoted per ball.

In my mind, tungsten only makes sense as low alloy spheres. You may lose 5-10% of the density, but it's still a clear winner over lead. The properties that make it a good bearing (polish and super hardness) are of no relevance to us and are expnsive to achieve. Even perfect roundness is unnecessary. A good sphere is all that's needed, as the higher density of tungsten makes up for a lot and the velocities that the vast majority of shooters achive (i.e. Everyone on the plant except torsten) are insufficient to put much spin effect on tungsten at target shooting or hunting distances. Ask yourself are cast lead roundballs perfectly round? They are usually off by quite a bit. All we need is lead roundball-quality roundness and that is calls for a casting process, not a bearing mill. I know spheres are sold, I just don't know who sells them in quantities we'd need even for a group buy.


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## philly

How about the Ammo companies, Federal sells tungsten shot shells someone there might have a link to a supplier.


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## Darb

Dan,

We're on the same page about what's needed and what to look for.









What I explained to the PoC at Salem ball is that I'm looking for an evaluation quantity of rough "ballast grade" shot pulled earlier in the production process, right after they've been stamped, but BEFORE they've been fire-hardened and polished. In other words, we're looking for rough slugs that still have their stamp-banding around the equator, aka "banded slugs" or "banded spheres".

I'll try them again in a bit, and post the results. If I can get 40 pieces of 3/8" for under $30, and I don't care from where or from who as long as the density is over 14 gr/cc, I'll probably go for it.


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## Rayshot

Darb,

Have you already inquired with stanfordmaterials.com ?

Or, any responses?

Since I like BBs, the BBs or BBBs at TungstenShot may be what I will try pending what you hear.


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## philly

Ray, tungsten BB shotshells have 54 BB per ounce you can get a box of 12 guage for around $26.00 or so, you may be able to get it from a reloading house by the pound cheaper. Midway may be a good source. Anyway, buy a box open one up, give it a try.Or if you have a duck hunting buddy get a freebie from him to try.
Philly


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## Darb

Been busy with medical issues, home repairs, and holiday stuff ... will followup soon.


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## Rayshot

Darb said:


> Been busy with medical issues, home repairs, and holiday stuff ... will followup soon.


Hopefully things will go smoothly!


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## Flatband

Know all about the medical issues of late.Hope I have some good news soon too. More to come. Flatband


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