Ballistics Gel Step by Step Regulation Testing Density

Ballistic Gel Recipe Done Correctly For Regulation 10%  by Weight and Proper Density

I'm a retired cop and have made both ballistics gel and used off the shelf unflavored gelatin,

The bellow recipe has worked for me for over 13 years. It gives the best results and as long as the steps are followed exactly and will result in calibrated FBI regulation ballistic gel. I got this recipe from  firearmstactical.com back in 2000 and its given better results than any other manufacture steps.

http://www.firearmstactical.com

Calibration of finished product by FBI staandard:
Complete calibration by using a air rifle or pistol shooting a steel BB into it at a velocity of 590 feet per second ± 30 fps. The BB should penetrate 8.5 centimeters. This test done on bare gel block with no fabric or clothing in front of the target.

Step 1: What you will need

• Vyse type 250A ordnance gelatin powder (1 kilogram) or 1kg Knox brand unflavored gelatin, 6 boxes give you just over 1kg of powder
• Triple beam balance
• Stainless steel or Pyrex mixing bowl (3 quart)
• 5 gallon plastic paint bucket
• Graduated pitcher (3 liter) or measuring cup (1 liter)
• Thermometer (capable of measuring fluid temperature of 130° F ± 10° F)
• 9 liters hot tap water (130° F ± 10° F)
• Electric drill
• Paint stirrer (w/ plastic propeller-type blades)
• 12cc hypodermic syringe
• Aquarium air hose (6 inches long)
• Propionic acid
• Large spoon
• Silicone spray mold release
• Gelatin mold (FBI size: 6"W x 7"H x 16"L)
• Refrigerator (capable of maintaining approximately 39° F)
• Thermometer (capable of measuring air temperature of 39° F ± 10° F)
• Kitchen size (13 gallon) plastic garbage can bags
• Ice chest (if transporting gel to range or outdoors and not using immediately)
• Stand for block, cheap or built wood table
• Pneumatic air rifle capable of shooting steel BBs at 590 fps
• Chronograph
• Ruler, metric (45 - 60 centimeters)
• Dial caliper
• Denim cloth (14.5 - 16 ounce) or other clothing patch or layers of clothing and coat to simulate clothing interaction.

Comments

[dad_a_monk]

One odd addition to this, I was once asked to make a block that would bleed on impact. The way I accomplished it was to take a small oval balloon about the size of a large cucumber. I anchored it vertically in the middle of the mold with string and a heavy weight at the bottom. So as the gel was poured into the mold the balloon stayed in the middle.

After the gel cured, I took a long large gauge needle and syringe used for injecting meats and filled the cavity with fake blood. I used clear syrup with food coloring. The balloon of course popped when I injected the needle but the cavity was still in tact. I did find I had to use a second needle without a syringe attached, injected at a downward angle into the top of the cavity to allow air to escape as I added the "blood" Otherwise the airtight nature of the gel would cause the cavity to expand as the liquid was added.

I have used this string method to add bones to the gel blocks. By weighting the string at the bottom and extending a second string upward and attaching it to a rod running across the opening of the mold, the bones stay in place where you want them. Otherwise they tend to shift around and may end up too close or too far from the exterior of the gel construct.

[neodymium]

Very, very nice 'ible. I didn't know anyone ever went so far as to make the "home version" meet FBI standards. This is definitely going into my bookmarks bar.

I've been trying to find a way to see what bb weights and velocities (airsoft) would penetrate flesh and which are safer. I once saw an airsoft bb go through somebody's cheek and into their mouth, with the offender claiming his airsoft gun was shooting within the limits. This will help me determine exactly what limits should be set on fps for each specific bb weight so we don't have any more incidents like that.

The Mythbusters made put into one of their episodes the process of how they make ballistic gel, and they add pour some cinnamon leaf oil onto their ballistic gel mixture to take away the foam. Do you think this would screw with the density of the ballistic gel or do you think it's a viable option to taking the time to scoop all the foam away?

[dad_a_monk]

To be honest, i have never heard of adding cinnamon leaf oil to stop the foaming. My thoughts are that it would depend on the amount used. I think if it is less than an ounce, the density shift would be nominal. If its more than that, i would substitute its volume from the water at a ratio of 1:2 to compensate for the density of the oil compared to water. So one part cinnamon oil substituting two parts water. This would be a very OCD approach, you would have to test it but i don't think it would change density.

Although i don't really see the foam removal as such a tedious step. The mixture is so viscous at that point, the foam is easily removed. I think i will try it next time I make a batch. If you beat me to it, please share your results.

Thanks for that.

[neodymium]

I don't have any means to measure out the gelatin mix at the moment, so you will probably be the one to make it with cinnamon leaf oil first. I'd be very interested if it does yield different results, because that would mean all the mythbusters results thus far when testing with ballistic gel have been invalid. Of course I'm not looking for that to happen because I love the mythbusters, but it would sure be interesting.

[dad_a_monk]

I made a batch for a torso mock up and tried the cinnamon oil trick. Now I did do as i said substituting water for the oil at a 2:1 ratio to compensate for the oil's density and viscosoty. I only added one ounce of oil and it did knock almost all the foam down. Also I conducted the FBI standards density test with a sample if the finished product, and it performed just as perfect as my normal formula.

For the ease of not having to deal with large amounts of foam, its worth the addition. It also gives the gel a slight cinnamon smell. So it smells good as its being blasted.

BIG THANKS to neodymium for making my life easier!!

[neodymium]

Well ya know, you can't shoot something that doesn't smell nice. It just isn't worthy of our bullets.

Glad it worked out. Guess the mythbusters have the right idea, adding cinnamon leaf oil to the ballistics gel.

I shared this 'ible with some friends who like to experiment with various projectiles (don't ask), and it helped them out a lot. They were making home ballistics gel using other 'ibles, and once they tested this formula out, they found all their other tests were invalid. So thanks for giving me a good laugh! Now I get to watch them do a million tests shooting things into ballistics gel, haha, (no sarcasm, it's really fun).

[dad_a_monk]

A few have asked me about the use of ballistic gel for edged weapons testing. Although penetration depth is relative to the user, it can't be used as a standard. It can be used as a personal test of various weapons and how they penetrate for the individual.

The gel can be used for forensic purposes to compare wounds and tool marks as well as cut and slash comparison. When used for this purpose I have found it good to add a dark food coloring to the mixture. The gel being darker and opaque makes for easier comparison.

When adding food coloring you must subsitiue the volume of food coloring for water in the process so as not to alter the density. Liquid food dies are safe but pain or thicker coloring agents are not since these would alter the density of the gel.

[bajablue]

Interesting... but can you tell me why a person would make this? What's the purpose?
Is it a forensics tool? Could you build bunker out of it? Not being snarky, I promise. I'd really like to know!

[ffcabral]

It is supposed to have the same consistency as human flesh, so ballistic gel may be used to test weapons, like projectile penetration or such. But not just firearms. In a TV Show, Gina Carano hit a human-shaped model made with this gel over a skeleton, she broke a couple ribs.

[dad_a_monk]

Exactly ffcabral, Thak you. A great point to make is that ballistic gel is designed to be an equvlant to human flesh, tissue and organs. It does not replicate the density of the entire human body. That's why I have talked about not only using bones as you stated by clothing samples in front of the test block. Both bone and fabric as well as any other obstacle between the firearm and target can greatly impact performance. A reson police officers use "hotter" rounds than most civilians. Not to ensure the suspect dies, but to ensure the person can be stopped.

In a real word shooting you have things like glass, metal and wood to sometimes get in the path,but even clothing can make a great buffer to slow a round. As I stated in a comment on an inferior recipe, a saw a case were the suspect was shot by a 9mm and the round didn't even fully penetrate his fat layer. He was a big guy, but he had a thick coat on made of denim and layers of clothing that combined to slow the round to an ineffective level.

No test is 100% when it comes to ballistic performance. Their are so many variables that no one test can take them all into account. However if you start with a massively underpreforming product like these quick jello jigglers recipes then you can not even begin with a baseline of performance .

[bajablue]

Thanks for explaining this to me!

[Jayefuu]

Great info! That was a really interesting read, far better than that jelly in a bowl Instructable ;)

[wilgubeast]

That jelly in a bowl Instructable is adequate for Call of Duty and maybe some light KNEX fire. This is my favorite kind of Instructable: someone leverages a real-life skill into something easily-replicable. When that kid gets some real police training, I imagine his skills will improve. This, though, is magnificent in its casual professionalism and detailed documentation. Kudos, dad_a_monk.

[dad_a_monk]

Thank you for that. My hope was that people would understand the difference. Unfortunately this is a process with no shortcuts and has to be done methodically to get the right result. Otherwise you get a complete false result. What's the point of making ballistic gel in 30 mins if the results it gives are more consistent with a pillow than a human body.

It may seem to some that these other quick made guides are "close enough" but in the end this gel is made to test ballistic penetration. If you use the wrong formula and thus wrong density you end up with false results. You may then put faith in a round that does not have anywhere near the penetration you believe It does. I have seens some cheap make 9mm ammo that penetrated less than a .22 short.

[ChrisKa]

Thank you for sharing your expertise, and for pointing out how some of the other instructables for ballistics gel would not be up to standard and, more importantly, why.

[valkgurl]

You used to be able to buy BULK KNOX gelatin at Food Service places--like Sysco here in the East--and surely this is avail on line or ask your friendly local bakery or restaurant---this is used in a lot of cooking stuff.

Prob save you a bunch and also if the gelatin has been sitting around on the store shelf for too long it won't dissolve right. You could also contact Knox and see if they will sell bulk directly--some companies are better at this than others--or ask your local grocery--the smaller the better here!-or even a hardware store that stocks canning supplies might be able to order it for you.

[festeezio]

Wow, that's thorough! Thanks so much for posting this. I need to go to the range.

[fungus amungus]

Thanks for posting this.