Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login
Site Notices
10/20/2017 1:01:18 AM
9/22/2017 12:11:25 AM
Posted: 9/28/2012 12:13:24 PM EDT
[Last Edit: 11/11/2012 6:19:38 AM EDT by bluefalcon]
So my lovely and thoughtful wife bought me a 10mm Witness for Christmas and I've had a lot of fun working up loads for it. Problem is there really isn't a whole lot of terminal ballistic data available so I have no idea which bullets will hold together well or penetrate to what depth. I did a couple water tests but those were less than definitive and disappointing if they were to be believed. Worse, it seemed that they were inconsistent with other available data. So anyway I decided the only way to get good data was to gather it myself. So here is my attempt at ballistic gel. Let me know how badly you think I did.

Proper ballistic gelatin is 10% by weight 250 bloom photographer's gelatin. That means 10% of the weight is gelatin and 90% of the weight is water. It is kept at 40° F and is calibrated by a .177 cal BB at 600 fps. The calibration shot(s) should be between 3.25"-3.75". 250 bloom photographer's gelatin is expensive so I bought grocery store unflavored gelatin. I did the math and found that 10% should put me at about 1 cup of water per ounce of gelatin. I bought three 8oz packages of Kroger gelatin and mixed it up with 24 cups of water but it didn't calibrate correctly. I bought another three 8oz packages, Knox this time and mixed it with 18 cups of water, melted both batches down and mixed together. So that's a total of 48oz of gelatin with 42oz of water.That got me about what I was looking for. My procedure follows.

Open all the packages into a bowl for easy pouring. Measure 42 cups of hot tap water into a bucket, along with 1/2 capful of bleach (to prevent mold) and a few drops of Jet Dry to prevent foaming. Start the water moving with a mixer and slowly pour in the gelatin. Be careful to pour slowly enough to avoid clumps but some are probably inevitable. Allow to cool and refrigerate for about a day. Heat in a double boiler until just melted, stir, and pour into molds. Allow to cool and refrigerate again for several days. It gets firmer after several days and it has to be all the way down to 40° throughout for calibration to have any meaning. Fire a 600 fps .177 cal BB into the block and measure the penetration. In the picture below, the bottom shot took place at about one day in the fridge and it measured 4". The shots above that took place at about three days and measure, bottom to top: 3", 3 1/8", 3 1/4", 3 1/8". This is just below the calibration threshold but I think I'm going to go ahead with this because my Crossman BB gun actually chronos at about 590 fps. The other picture was a .22 cal pellet from a Benjamin Sheridan pellet rifle just for fun. It penetrated 4 1/2".

Let me know what you think and please share any advice.

Link Posted: 9/28/2012 5:27:59 PM EDT
This is one of the coolest DIY projects I have ever seen.
Link Posted: 9/28/2012 6:05:24 PM EDT
I think that's pretty cool
Link Posted: 9/29/2012 11:36:27 AM EDT
[Last Edit: 9/29/2012 11:38:43 AM EDT by bluefalcon]
Here's a new test with a bit more precise data:

BB calibration: 590.8 fps, 3" penetration
.22lr from Walther P-22: 36 gr CCI Mini-Mag hollow point at 970.0 fps, 8 3/8" penetration
I got distracted by something shiny and forgot to place 4 layers of denim in front of the .22lr shot.

I'm thinking I may want to remelt the blocks and add a half cup of water until I can get a calibration shot that's actually between 3.25"-3.75". The more I think about it, the less it seems that 9 fps can really account for a quarter inch of penetration. Really a half inch from the ideal. I want to just get on to shooting these blocks but I want to be sure it's really right before I do. On a side note, it's pretty hard to get good pictures. I need to play around with lighting to really capture the track through the gel.

Link Posted: 9/29/2012 11:54:37 AM EDT
We need to get the MOD's to sticky this thread!

Link Posted: 9/29/2012 12:22:45 PM EDT
Let's see if I can get some consistent and repeatable results first. Otherwise, it won't be a lot of use to others. I sure do appreciate the confidence, though.
Link Posted: 10/1/2012 2:07:51 PM EDT
I went ahead and melted the blocks down to mix in a cup of water. I think I might actually need two cups but you can always add more water. It's a lot harder to get the water out. I poured the gel through a screen and took a pic and measurements of the .22lr. The retained weight was 35.7 gr and the diameter was approximately 0.335". I didn't find any fragments. There was absolutely no deformation on the pellet.

Link Posted: 10/1/2012 5:24:06 PM EDT
so can you use this stuff indefinitely? Just melt it down and reform it? Does it last a long time outside then or does it melt down?
Link Posted: 10/2/2012 8:29:01 AM EDT
You can't use it forever. It will eventually start getting clouded up with junk from being shot. A previous experiment started to mold, hence the bleach in this one. You can melt and reuse it many times and as long as it still calibrates correctly, I don't see any problem.

On the outside thing, it is very sensitive to temperature in that if it's off from 40° by very much, it won't properly calibrate. It's very important to keep it at temperature until immediately before you shoot it. When I melted this batch down I thought I would be clever and leave one block outside in the sun while the other one was on the stove so that it would be warmer and would melt quicker. That was a mistake. This stuff is really easy to handle when it is fully solid or fully liquid. It's a mess when the outside is sloppy snot and the inside is still solid.
Link Posted: 10/4/2012 8:44:42 AM EDT
[Last Edit: 10/4/2012 9:25:16 AM EDT by bluefalcon]
Recalibrated today and I'm dead on 3" again with a BB velocity of 595.9 fps. I'm going to remelt and add two cups of water. I'm going to shoot this SOB on Saturday, regardless of how it calibrates. I have more opportunities to fiddle with the mix than I do to get out and shoot. I think I'll hit it with a 165 gr Gold Dot at 1,302 fps first.

ETA: While I was melting down one block, I shot some BBs into the second block but without the chrono. Three BBs all hit 3.25". Both blocks were made at exactly the same time so my only explanation is that the second block, the one that had been on the bottom in the refrigerator, was slightly warmer. It's still kinda odd because the last time I shot both blocks and got the same calibration from both and they've been in the fridge about the same length of time as the last time.
Link Posted: 10/7/2012 4:39:44 AM EDT
So how did the test go?
Link Posted: 10/7/2012 9:01:30 AM EDT
Link Posted: 10/7/2012 6:16:55 PM EDT
[Last Edit: 10/7/2012 6:17:54 PM EDT by BlueCord]
Might want to watch some of TN9outdoors videos on YouTube, dude takes this ballistic stuff seriously!

Link Posted: 10/8/2012 9:28:15 AM EDT
Originally Posted By BlueCord:
Might want to watch some of TN9outdoors videos on YouTube, dude takes this ballistic stuff seriously!


I've seen those. Pretty neat. I'm still working on my test methods so don't expect anything as polished as his results. I'm compiling everything now and should post soon.

Link Posted: 10/8/2012 10:59:55 AM EDT
I had some trouble with my chrono and it missed the velocity on several BB calibration shots. There were also a few that came in well under the acceptable velocity of 590-610fps. My BB gun seems to shoot faster when it's cold. Maybe I'll keep it in the cooler with the gel next time. I finally got a couple shots that were close to the right velocity so the calibration shot will be 586.4 fps (still a touch low) and 3.5". The 10mm shots are taken through 4 layers of denim using an EAA Witness 4.5" barrel.

First up is 180 gr XTP over 11.8gr of AA#7, 2.255" COL, at a measured impact velocity of 1,290. Penetration is 13.25". It exited the first block and went a about an inch and a quarter into the second block. Next time I'll have to cut the blocks even so there is no air space between them. I don't know how much, if any, effect that has. You can see that this bullet fragmented a bit. I was going to weigh the recovered fragments, but the piece you see in the on picture got left out there. Sorry. Maximum expansion is 0.898" and minimum is 0.636". Retained weight is 174.8 gr.

Since the XTP barely touched the second block, I reversed it and placed it at the front. Next up is 165 gr Gold Dot over 12.3 gr of AA#7, 2.255". I missed the actual impact velocity of this shot but the average for this load is 1,310 fps. Penetration was 12". This shot exited the first block and was found laying between the two. There was absolutely no fragmentation or jacket separation. These Gold Dots are TOUGH. Maximum expansion was 0.837" and minimum was 0.779". Retained weight was 165.0gr.

Link Posted: 10/8/2012 12:11:50 PM EDT
So the actual mix looks like it was 24 oz of Kroger brand gelatin, 24 oz of Knox brand gelatin (I'm not sure if the brand makes any difference), and 21 cups water. That yields about three gallons of the gelatin mix. In the molds I used that made two blocks about 12"x4"x8". It costs me about $6.50 per 8 oz box of gelatin. Half as much should be enough to test most handgun rounds if you don't care what the exact penetration is. That is to say, if the round goes through 12" of gelatin and stops in a jug of water, you know that it meets minimum requirements.

If you do it for yourself, I'd recommend you start with 19 or 20 cups of water in case your mix ends up a touch harder. It's a lot easier to add water than to get it out.

To recap, you'll want to add some Jet Dry to keep it from foaming and a half cap of bleach to prevent mold. Slowly pour the gelatin powder into warm tap water while running a mixer and try to avoid clumps as best you can. Refrigerate for a few hours to give the gelatin time to absorb water, then melt in a double boiler and stir well. Pour into molds and refrigerate long enough to be sure the whole block is down to 40 degrees. Calibrate with .177 cal BB at 600 fps +/- 10 fps. Penetration should be between 3.25"-3.75".

I recognize that one shot per cartridge doesn't give a statistically significant sample but I just don't have the resources to fire five or more shots into gel on one trip. Once I test a few of the cartridges on my list, I think I'll go back and retest a few with multiple shots to see how much variation there really is. Most well constructed bullets don't show a lot of variation in proper ballistic gel.
Link Posted: 10/8/2012 4:00:02 PM EDT
Tag, with lots of questions for the OP later on when I get home. Awesome thread so far.
Link Posted: 10/11/2012 8:46:03 AM EDT
I'm going to shoot this stuff again Saturday, if we can get a sitter. I plan to fire at least one shot of .40 S&W 180 gr factory Gold Dot into it from my Glock 22 to help establish a baseline. On the one hand I'd like to get on with testing lots of other loads but on the other hand I think I need to address the concern that my gel may not yield accurate results. To that end I was thinking that I could probably get two shots into each block, for a total of 4 shots. So what do you think? Should I shoot the block four times with .40 or is one shot sufficient to tell us whether the gelatin is close? If I only shoot it once with the .40, what other load do you want to see tested? The two I'm most interested in seeing are Buffalo Bore 10mm 180 gr JHP and my hand loaded 65 gr Game King over 24.0 gr of TAC at about 2,950.
Link Posted: 10/13/2012 7:45:47 PM EDT
[Last Edit: 10/13/2012 8:23:25 PM EDT by bluefalcon]
Otay, I got a chance to go out again today and play with my jelly. the results are below. Sorry but my video camera died. I have crappy video from my digital still camera I might post later.

BB calibration was 603.4 fps and 3.5"

I fired two rounds of factory .40 S&W 180gr Speer Gold Dot from a Glock 22 into one block. In the photo, the top round had an impact velocity of 1,027 fps and the bottom round had an impact velocity of 988.0 fps. They penetrated 11.25" and 15" respectively. Both were fired through four layers of denim. One bullet literally stopped between the two blocks. I'll post pics and measurements of recovered bullets after I melt the blocks down.

Next up was my hand loaded 65gr SGK over 24.0gr of TAC (this is a 5.56mm pressure load), which had an impact velocity of 2,808 fps and penetrated 12". I also fired a 75gr Prvi Partisan BTHP into the block that had been shot by .40 already but I don't have any good pictures. I'm also not really confident the results are very relevant considering the block had already been shot twice. I didn't get the impact velocity but I did do a five shot average which was 2,670 fps. It penetrated 14".

Finally, I fired one of the 65gr hand loads into a steel plate located about 6-8" from the gelatin to see how bad the fragmentation from a steel plate is. The first pic is before I rinsed the dirt off.

While we were out there a helicopter crew came out to start working on the high tension lines. They weren't exactly down range but I figure their job is stressful enough without worrying about drunken hillbillies shooting in their direction so we packed it up.

Link Posted: 10/16/2012 8:46:10 AM EDT
Crappy video (sorry, my camcorder battery died):

Link Posted: 10/16/2012 8:50:23 AM EDT
The bullet that impacted at 988.0 fps and penetrated 15":

Min expansion: 0.705"
Max expansion: 0.805"
Retained weight: 178.0 gr

The bullet that impacted at 1,027 fps and penetrated 11.75":

Min expansion: 0.622"
Max expansion: 0.650"
Retained weight: 178.5 gr

The 65 gr 5.56mm hand load:

Min expansion: 0.412"
Max expansion: 0.547"
Retained weight: 34.9 gr

The 75 gr Prvi Partisan BTHP:

Min expansion: 0.355"
Max expansion: 0.594"
Retained weight: 46.4 gr

Wait, wut? BTHP bullets aren't supposed to expand. They usually yaw and then fragment but it sure as hell looks like this one expanded.

Link Posted: 10/16/2012 9:09:41 AM EDT
Link Posted: 10/16/2012 10:53:12 AM EDT
Love me some 10mm

Link Posted: 10/22/2012 9:53:28 AM EDT
[Last Edit: 10/30/2012 8:12:34 AM EDT by bluefalcon]
Thanks, Rifleguy81, for your help and for letting me shoot your target.

BB calibration was 597 fps and 3.25" for one block and 602 fps and 3.75" for the other block.

First up: 200 gr XTP over 8.1 gr of 800-X. I forgot to place the denim over the block for this test. At first I was pretty disappointed but I had intended for this load to be my woods load and critters don't usually wear clothes. From other tests I know that the XTP still performs through denim and generally JHPs seem to penetrate a bit less in bare gelatin. Anyway, it is what it is. Sorry I forgot. I'll definitely retest with the denim. The first shot had an impact velocity of 1,134 fps and penetrated 15.75". The second shot had an impact velocity of 1,142 fps and penetrated 15.5".

Next is 180 gr Buffalo Bore. The first shot impacted at 1,335 fps and penetrated 14.5". The second shot impacted at 1,330 and I got distracted by something shiny and neglected to measure penetration.

Next, I fired some Yugo M67 ball into a steel target, first with bare gelatin, then with denim covering. The first shot shows the effect of 3 shots on bare gelatin vs. one shot "protected" by denim.

200 gr XTP:

Bullet #1
Retained weight: 182.3 gr
Max expansion: 0.683"
Min expansion: 0.622"

Bullet #2
Retained weight: 187.8 gr
Max expansion: 0.690"
Min expansion: 0.601"

180 gr Buffalo Bore:

Retained weight: 167.8 gr
Max expansion: 0.734"
Min expansion: 0.670"

Link Posted: 10/30/2012 8:13:09 AM EDT
I retested the 200 gr XTP at a lower velocity and with the addition of denim. Good news: it goes plenty deep at this velocity when fired through denim. Bad news: it REALLY doesn't want to expand. All three shots failed to expand and only one came to a rest inside the gelatin. Unfortunately, because of this and because one of the Gold Dots left the side of the block, both blocks had been shot up pretty badly and really didn't give the opportunity to take any good pictures.

200 gr XTP @ 1,037 fps:

180 gr Gold Dot @ 1,317 fps:

Next up: 65 gr Sierra Game King hand load and 75 gr Prvi Partisan BTHP. Both from 11.5" AR. Unless I get distracted by something shiny.
Link Posted: 11/11/2012 6:19:50 AM EDT
Top Top