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gotigers
07-15-2013, 07:25 PM
I want to test several loads. This will not be a scientific test. Data exactly like FBI gel test is not needed, but i want something that will give me consistant results. With consistant results i will be able to compare my results with published results. Gelatin is not cheap and i have several loads to test.

I want to compare cavity results more than bullet expansion.

I have read of some people using a corn starch/water mix, cardboard/water mix, paper/water mix and phone books soaked in water.

Any of those vialbe or are there others?

Edit: Another reason i want an alternative, i want something less sensative to temperature. Transporting gelatin to my range in the heat of summer would be problematic.

BLR
07-15-2013, 07:39 PM
I want to test several loads. This will not be a scientific test. Data exactly like FBI gel test is not needed, but i want something that will give me consistant results. With consistant results i will be able to compare my results with published results. Gelatin is not cheap and i have several loads to test.

I want to compare cavity results more than bullet expansion.

I have read of some people using a corn starch/water mix, cardboard/water mix, paper/water mix and phone books soaked in water.

Any of those vialbe or are there others?

Edit: Another reason i want an alternative, i want something less sensative to temperature. Transporting gelatin to my range in the heat of summer would be problematic.

Well, first off, startch-water is shear thickening. So that wont work.
Cardboard-water has compressible fibers in it (the cellulose, as it stands) at a significantly large volume fraction. So that wont work. And the binder used in the cardboard, is a non Newtonian fluid also. So there's that.
Paper-water is basically the same as above, with slightly less compressablility.

You want to test the cavity, ok. Pick a medium that mimics tissue. Gel or water. For gel, if it is a relative comparison, you have only to calibrate or find a way to normalize the results.

Proper ballistic analysis is more than shooting calibrated jello and comparing expanded bullets and penetration depth.

gotigers
07-15-2013, 08:26 PM
Snip

Proper ballistic analysis is more than shooting calibrated jello and comparing expanded bullets and penetration depth.

I completely understand that. I said, my test will not be a scientific test. This info will be to help me be more comfortable with my choices.

Let me be more specific about what i want to accomplish. I have a stamp coming for a 10.5" SBR and will eventually have a suppressor. I want to use this for home defense. I have read everything i can find about 5.56/.223 terminal ballistics including Dr. Roberts writings. Since this weapon will be used in my home, i want a non-barrier blind bullet or as close to it as i can get. I believe a heavy OTM will be what i want. However, i have shot enough to know that no two barrels shoot ammo the same. I want to test several rounds from my barrel to find the best round my needs.

Maybe i am overthinking it, but i enjoy shooting and this gives me a reason to shoot lots of different ammo.

If ballistic gel is the only real choice, so be it. I couldn't find any real alternative on google, but I figured there is no harm in asking. I don't have a lab and i am paying for this out of my pocket. Gel is only one of the tests i will be conducting.

Thanks for the input.

secondstoryguy
07-15-2013, 10:56 PM
Its not ballistic gel but I've found that shooting deer and hogs with my defensive ammo has given me some good unofficial data on its terminal performance. The byproduct of the "testing" is very yummy.

Archimagirus
07-16-2013, 02:00 AM
I have often thought about this subject myself. Coming at the problem from a foodies perspective, you might want to look at Agar Agar. While this is an overly simplistic comparison, it is basically vegetarian gelatin. It is derived from seaweed and more stable across a wider range of temperatures than gelatin. There is also the molecular gastronomy route of using sodium alginate and calcium chloride to make a room temperature gel without heat.

All of these options may, or more probably may not, be more cost effective than standard ballistic gelatin.

Byron
07-16-2013, 07:54 AM
No experience with it personally, but there's always this stuff: http://clearballistics.com/

It doesn't solve the cost issue, but it addresses the temperature sensitivity issue.

ToddG
07-16-2013, 08:07 AM
My guess -- and I cannot speak for DocGKR -- is that if a cheap, easy, durable alternative to properly calibrated ballistic gelatin existed, he'd be using it instead. If some other medium provided results that correlated strongly with ballistic gelatin data then the expense and difficulty of dealing with the ballistic jello would be unnecessary.

gotigers
07-16-2013, 07:20 PM
My guess -- and I cannot speak for DocGKR -- is that if a cheap, easy, durable alternative to properly calibrated ballistic gelatin existed, he'd be using it instead. If some other medium provided results that correlated strongly with ballistic gelatin data then the expense and difficulty of dealing with the ballistic jello would be unnecessary.

true, that is the rub. I don't expect perfect results.

DanH
07-16-2013, 07:34 PM
I would think the answer to your dilemma would depend on just how scientifically valid you intend your results to be. The famous, or infamous, Box o'Truth (a series of water-filled milk jugs) does have one advantage over wet phone books, and that is that it is a consistent standard that can be maintained through many gun and ammo types.
As long as you don't make the mistake of comparing the results to the results obtained by ballistic gelatin tests, you can use any consistent, reproducible medium your heart desires. The main thing to keep in mind is that the results of water-jug-type tests can't be compared to anything but other water-jug-type tests.

BLR
07-16-2013, 08:09 PM
I would think the answer to your dilemma would depend on just how scientifically valid you intend your results to be. The famous, or infamous, Box o'Truth (a series of water-filled milk jugs) does have one advantage over wet phone books, and that is that it is a consistent standard that can be maintained through many gun and ammo types.
As long as you don't make the mistake of comparing the results to the results obtained by ballistic gelatin tests, you can use any consistent, reproducible medium your heart desires. The main thing to keep in mind is that the results of water-jug-type tests can't be compared to anything but other water-jug-type tests.

In reality, ballistic gel isn't as true or valid a stimulant as most would believe. It is more a consistent, repeatable medium that often gives a microscopically similar penetration depth as live tissue.

The problems are many fold, and often not discussed. Ballistic gel is, from a scientific standpoint, wonderfully consistent, inexpensive, and available. It is totally homogeneous, and as such there is much debate as to how good of a hydraulic stimulant it actually is for ballistic tests.

Tissue, and for that matter water and ballistic gel, are mostly incompressible fluids, with varying levels of complexity. I don't think anyone would have issue with that statement. The problem is, and this has not been effectively addressed with any publications I am aware of, that the fluid properties (I am using the term "fluid" here liberally) have not been studied between the most common mediums. Especially in the supersonic range (that is, the supersonic velocity in the medium). What is the compressability of gel vs tissue vs water? What kind of tissue? What concentration of gel? Again, the crush, cut and tear properties of tissue are not as similar to gel as many would have believed. The gel is really a means to make a "solid" water, and not much more. What is the tensile strength of gel vs tissue?

There are some parafins on the market, and some silicone compounds that are being studied, but these also have their own issues. I am aware of some tests that use gum arabic as a tensile modifier for ballistic gel, and those results are questionable. Once you start getting scientific, questions arise like shear strength, tensile strength, elasticity, tear strength, apparent/microscopic viscosity, energy transfer rates, strain rates, and so on.

So, my recommendation, which is worth exactly what you are paying for it, would be to define the performance you want from the projectile. Is it 12" of penetration in a person after penetrating x/y layers of clothing? If so, use water. It will be as close as anything to giving you valid results. And be correlatable with previous studies.

ETA: If you are looking for a good initial treatise on ordnance gelatin, here you go: http://sem-proceedings.com/09s/sem.org-SEM-2009-Ann-Conf-s038p03-Tensile-Deformation-Fracture-Ballistic-Gelatin-as-Function-Loading.pdf
(I take some issue with the use of the term "crack" in describing the tearing of the gel, as crack propagation is distinctly different that the mechanism seen in that article, IMHO. Just food for thought.)

nycnoob
07-17-2013, 06:28 AM
This guy does lots of tests with clear Ballistic Gelatin
http://mousegunaddict.blogspot.com/p/ammo-tests.html


You might get some ideas on how to perform the tests you want.
Or perhaps he has already done the tests for you.

CougarRed
07-20-2013, 12:41 PM
No experience with it personally, but there's always this stuff: http://clearballistics.com/

It doesn't solve the cost issue, but it addresses the temperature sensitivity issue.

Clear Ballistics Gel has now been tested against true 10% Ordinance Gel. See the video below.

The findings are that for BBs, the 2 are virtually identical. Hollowpoints penetrate 5% more in Clear Ballistics Gel, and expand 5% less.

Given that it's odorless, can be re-used, and is not temperature sensitive, sounds like a great alternative to true 10% Ordinance gel if you normalize your results to account for the 5% differences in penetration and expansion.


https://www.youtube.com/watch?v=1kjcoFaobeo

the Schwartz
07-20-2013, 10:40 PM
I want to test several loads. This will not be a scientific test. Data exactly like FBI gel test is not needed, but i want something that will give me consistant results. With consistant results i will be able to compare my results with published results. Gelatin is not cheap and i have several loads to test.

I want to compare cavity results more than bullet expansion.

I have read of some people using a corn starch/water mix, cardboard/water mix, paper/water mix and phone books soaked in water.

Any of those vialbe or are there others?

Edit: Another reason i want an alternative, i want something less sensative to temperature. Transporting gelatin to my range in the heat of summer would be problematic.

There are only two accepted ballistic test mediums that I am aware of that'll give consistent results- calibrated gelatin and water- and water is very insensitive to temperature changes. All you need is a Fackler Box (very easy to build) and you are in business.

Fortunately, there are two books that cover water tests and have mathematical models that'll make it possible to figure out all the important stuff using bullet weight, velocity, and average recovered diameter.

"Bullet Penetration (http://pw2.netcom.com/~dmacp/)" by Duncan MacPherson and "Quantitative Ammunition Selection (http://quantitativeammunitionselection.com)" by Charles Schwartz.

Good luck.

DocGKR
07-24-2013, 12:17 PM
Have any of you guys actually carefully watched the linked video above comparing Clear Ballistics Gel and 10% ordnance gel???

It definitively illustrates the problems we've observed with all of the synthetic gel substitutes so far--the TC is not accurately represented.

This is less of an issue with handgun projectiles, but becomes significant when assessing rifle rounds. The synthetic gel substitutes are OK for simple expansion/penetration depth for handgun load, but then water works as a rough guideline for that already.

The synthetic materials are a useful backing material for body armor testing.

BLR
07-24-2013, 12:20 PM
Have any of you guys actually carefully watched the linked video above comparing Clear Ballistics Gel and 10% ordnance gel???

It definitively illustrates the problems we've observed with all of the synthetic gel substitutes so far--the TC is not accurately represented.

This is less of an issue with handgun projectiles, but becomes significant when assessing rifle rounds. The synthetic gel substitutes are OK for simple expansion/penetration depth for handgun load, but then water works as a rough guideline for that already.

The synthetic materials are a useful backing material for body armor testing.

If even that.

DocGKR
07-24-2013, 01:52 PM
Either do testing correctly or don't do it at all--anything else is a waste of time and tends to publicly reveal levels of ignorance that might best be kept private...

abu fitna
07-24-2013, 06:30 PM
I guess it depends on what one wants to get out of the test. Sure, controlled lab conditions are not present, and the material may not be a perfect match for other datasets. But there is something to be said for confidence demonstrations and other less than lab perfect data acquisition tasks. Its not capital S "Science", but there is something to be said for at least some value in the mythbusting type scenarios.

I know of a few instances where similar exercises may have been conducted with less than ideal test media, under highly austere conditions, for similar demonstrative purposes. There is sometimes a need to illustrate teaching points to indigenous audiences whose literacy and intellectual experiences may have meant that abstract textbook discussions of ammunition selection would be insufficient to instill the kind of confidence one seeks to see in a fighting man's regard for his carry load. While these factors may not be quite the same for an audience in the developed world, there are underlying principles that may reach deeper than mere classroom time can do so readily - and we are not so limited in CONUS as to have to make do with whatever offal or other tainted meat might be procured afield.

In that light, there is something to be said for having a product shipped from a manufacturer which presumably has a measure of quality control indicating at least consistency, even if not full fidelity to a more established test material. After all, I'll quote Segletes' observation on gelatin test result variability from APG here:

"As to why there is this slight systematic disparity, one possibility is offered here for
consideration. Hydrated ballistic gelatin is a material unlike most targets of ballistic
interest in that several key phases of the preparation are performed, not in a
manufacturing plant but by the end user. These key phases include hydrating the gelatin
powder to the right concentration in water of the proper temperature, mixing the
solution to maximize homogeneity while minimizing void content, and refrigerating the
hydrated liquid gelatin to the proper temperature until the material sets. With all these
key phases in the hands of the end user, it is perhaps not surprising that if two
laboratories were to start with the same gelatin powder, they might produce batches of
20% ballistic gelatin with slight, yet systematic variations in mechanical properties."

This is not to defend the clear gel products, as I haven't used this stuff, and have no view either way on the material itself other than comments on an earlier video, also not conclusive in any fashion.

Whether a Fackler type water test measuring expansion would do just as well is entirely valid for comparative discussion. But there is something to be said for folks getting their hands dirty with jello - and maybe over time maturing to a formal protocol; so long as the limits of one's observations in less than formal settings are known and noted.

Chuck Haggard
07-24-2013, 06:37 PM
One of the things I am looking to use the clear gel or alternates for is QC testing of new batches of duty ammo we buy, 20,000 rounds at a time.

In the past Doc has noted such failures as Ranger-T rounds that were made on old tooling and thus would not expand, unfortunately this was discoevered in real OISs IIRC.

One of the things I do with new duty ammo is to visually inspect a sample, test fire for function, and crono for velocity, before we issue any out. It would be nice to have a block to clear gel to drape some denim over and do a few tests shots. The hard numbers wouldn't be quite as important as insuring that the rounds are in fact expanding as designed and in the ball park of performance that we expect.

If the clear gel works for this role, and perhaps armor testing, then it will do what I need it to do. What I don't need is to reshoot tests that the FBI BRU and Doc have already completed, their data is far better than what I can come up with on my own.

BLR
07-24-2013, 06:41 PM
One of the things I am looking to use the clear gel or alternates for is QC testing of new batches of duty ammo we buy, 20,000 rounds at a time.

In the past Doc has noted such failures as Ranger-T rounds that were made on old tooling and thus would not expand, unfortunately this was discoevered in real OISs IIRC.

One of the things I do with new duty ammo is to visually inspect a sample, test fire for function, and crono for velocity, before we issue any out. It would be nice to have a block to clear gel to drape some denim over and do a few tests shots. The hard numbers wouldn't be quite as important as insuring that the rounds are in fact expanding as designed and in the ball park of performance that we expect.

If the clear gel works for this role, and perhaps armor testing, then it will do what I need it to do. What I don't need is to reshoot tests that the FBI BRU and Doc have already completed, their data is far better than what I can come up with on my own.

I'll bite - how was that arrived at? I assume the Ranger-Ts looked normal. How did the tooling cause the bullet to fail to open?

Chuck Haggard
07-24-2013, 06:44 PM
I'll bite - how was that arrived at? I assume the Ranger-Ts looked normal. How did the tooling cause the bullet to fail to open?

The tooling didn't cut the skives in the jacket as they should have, just as a dull knife doesn't cut as well as it should.

Haraise
07-24-2013, 06:45 PM
Given that water, per Doc just above, works as an expansion test, why would someone use a gel instead of simple water for bulk expansion testing?

Chuck Haggard
07-24-2013, 06:59 PM
People want to see the track left behind in gel, and water is a best case scenario if a bullet will expand or not. Many bullets that expand in water won't in a 4LD gel test.

ShootingTheBull
07-25-2013, 06:51 PM
Have any of you guys actually carefully watched the linked video above comparing Clear Ballistics Gel and 10% ordnance gel???

It definitively illustrates the problems we've observed with all of the synthetic gel substitutes so far--the TC is not accurately represented.

This is less of an issue with handgun projectiles, but becomes significant when assessing rifle rounds. The synthetic gel substitutes are OK for simple expansion/penetration depth for handgun load, but then water works as a rough guideline for that already.
I'm the guy who produced that video, and someone pinged me that it was being discussed so I hope you don't mind if I drop by...

I'd like to say that I agree with Doctor Roberts about this. If you watch the video all the way through, well, especially the end wrap-up part, I say as much. I think this synthetic gel is a perfectly reasonable substitute for ordnance gelatin, for the purpose of testing pistol rounds.

What it doesn't do, is it doesn't represent the temporary stretch cavity the way traditional ballistic gel does. And that's not really usually an issue with handgun rounds; the temporary stretch cavity isn't usually big enough to cause any substantial wounding. But with high powered rifles, the TSC can be a significant factor in wounding and would best be served to be represented accurately.

For those who are looking for penetration, recovery of expanded bullets, and want to do so in a three-dimensional medium, I do think the ClearBallistics gel is really useful for that. It's not identical, obviously, but it correlated reasonably well against the genuine stuff.

For those who are testing rifle projectiles, and who want to see the massive damage cavity caused thereby, or who want to dissect the block and dig into the wound channels, then the synthetic ballistic gel isn't suitable for that, and 10% ordnance gelatin remains the most suitable, and most accurate, tissue simulant.


The synthetic materials are a useful backing material for body armor testing.
Sure, but don't you also agree that they're suitable for the backyard ammo tester, the do-it-yourselfer, the cost-conscious consumer who doesn't have the facilities to easily store multiple 20-lb blocks in his fridge and then be able to put them immediately on the range? I mean, I'll tell ya, just loading up the glass shelves in the fridge with sixty pounds of hot sticky goo for three days at a time is enough for the wife to give you the ol' stink eye...

I'm of course not referring to what products are better for professional testing by dedicated professionals; I'm just speaking about the person who wants to conduct tests of his or her own self-defense weapon with their chosen carry ammo. Basically, like the original poster here (although I gather they want to use a 5.56 pistol, and I don't know if the synthetic gel would be appropriate for that or not...)

As far as water goes, water can of course be a very useful medium as well. I've done substantial testing with the Schwartz formula and a Fackler box, and for calculating accurate penetration and mass of the permanent wound cavity, there's no more affordable way to get truly accurate results. Water testing, done right, can be really accurate.

Al T.
07-25-2013, 08:09 PM
On your other videos, I appreciate you using five shots. :)

ShootingTheBull
07-26-2013, 07:57 PM
On your other videos, I appreciate you using five shots. :)Thanks! Wish I could have done it with the first video, but I had to make a choice, and I wanted to get a handle on the full spectrum of the gel, not just on how it performs with one round. If it was wildly inaccurate with hollow points, or with solids, I wanted to know that, so I chose to use a range of types of rounds, rather than multiple shots of just three rounds.

Obviously if I had my preference I would have had a dozen blocks of ballistic gel, and tested six rounds, 10 shots each. As it is, I'm kind of having to rely on the averaging across different rounds to come to a conclusion. Not ideal, but that's what happens when circumstances dictate that you have to compromise...

On my other videos, I'm not testing the gel, I'm testing the round itself, so yeah, five shots is a minimum to get a bit of a broader spectrum of how the rounds themselves actually perform.