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Old December 22, 2012, 12:08 PM   #1
Andrew Wiggin
Senior Member
 
Join Date: December 22, 2012
Posts: 156
Homemade ballistic gelatin testing

Proper ballistic gelatin is made from 250 bloom photographer's gelatin. Problem is, that stuff is fairly expensive. According to Vyse, the gelatin they use is 250 +/- 5, whereas food gelatin is typically 250 +/- 10. There are also variations in other metrics, which you can read about here. While these variations may invalidate tests for a ballistics lab, I feel that the results should be close enough as to be useful for the layman to get a general idea of how certain loads perform, especially with cartridges such as the 10mm where there just isn't hardly any good, professional data available. At the very least, the data collected should be far more relevant than water or wet pack and probably more accurate than Simtest or Cleargel. I have verified this by shooting my gelatin with a factory Speer Gold Dot 180 gr .40 S&W and a 75 gr PPU BTHP. In the former case, the result was practically identical to a published FBI test and in the latter case, the results were nearly identical to Molon's (from AR15.com and M4carbine.net) test of the same cartridge. I used grocery store gelatin and had to do some fiddling to get the mix right but was eventually able to get consistent calibration results. Proper calibration is a .177 BB fired at 590 fps +/- 15 fps into a 40 degree block of gelatin. Penetration should fall between 2.95" and 3.75". I initially had some trouble getting the right velocity out of my BB gun but I think I've got it figured out now. Here are some of my tests. Penetration, expansion, retained weight, etc. values are in the descriptions for each video.

I use grocery store unflavored gelatin in a ratio of 45 cups of hot water to 48 oz of gelatin, which yields about 2.5 gallons of the mixture. I've since made another batch for a total of about five gallons. The cost is about $6.50 for an 8 oz box of gelatin.

I start by measuring out 45 cups of hot tap water and adding a few drops of bleach (to prevent mold), jet dry (to prevent foaming), and cinnamon oil (to clarify). I then slowly add the gelatin while running the mixer. It's easier to just open all the packets first into a bowl. I try to avoid chunks but I think some are inevitable. Once it's all mixed, it goes into the fridge for about a day. This is necessary to give time for the gelatin to fully hydrate. Then I heat it in a double boiler (actually just a two gallon bucket in a large pot) on the stove to remelt it, stir it well with a long spoon and pour into molds. Then it goes into the refrigerator at 39 degrees F. It needs to refrigerate for at least 3 days to fully cool on the inside. It will need to be calibrated immediately before shooting but you may also want to test it at home to be sure your mix is right before heading out to the range.

Proper calibration is a .177 cal BB at 590 fps +/- 15 fps and the penetration should be between 2.95" and 3.75". If you make multiple blocks, they must each be calibrated.


I've done several different tests and they are all posted to my YouTube channel. Test data is in the video description. I've done several 10mm tests and I'd like to do more, but I also want to test cartridges and loads that may be used for defense but don't see a lot of official testing. Say 7.62x39mm Wolf HP, for example. Here are a couple, if you'd like to see some others, visit my YouTube channel:


10mm MAC Razorback, 165 gr Montana Gold JHP:

YouTube video






.223 75 gr Privi Partisan BTHP:

YouTube video



The largest recovered fragment (19 gr):

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