Ballistic test: .44 mag from a carbine and 10mm 135 gr cast bullet

[chopinbloc]

.44 mag Winchester 240 gr JSP fired from Marlin 1894 carbine into calibrated gelatin and calibrated tactical rain water.

BB: 594.1 fps, 3.4"

Gelatin test data:

Impact velocity: 1,848 fps
Penetration: 21.1"
Retained weight: 231.4 gr
Max expansion: 0.711"
Min expansion: 0.732"

Sorry about the cross section of the wound channel. This load really crushed the block and caused a substantial amount of disruption, especially in the first 10" or so. When I cut into the block for the cross section photo it practically fell apart. The photo really doesn't do justice to the damage that was done.







10mm 135 gr Mihec 10:1 lead/tin alloy over 12.5 gr SR 4756 fired from 4.25" barrel S&W 1076 through four layers of denim into calibrated gelatin.

BB: 594.1 fps, 3.4"

Gelatin results:

Impact velocity: 1,548 fps
Penetration: 7.1"
Retained weight: 73.0 gr
Min Expansion: 0.651"
Max expansion: 0.708"

We fired a few rounds over a chronograph with the same powder and alloy but different charge weights and these are the velocities we got:

11.0 gr 1,512 fps
11,5 gr 1,484 fps
12.0 gr 1,568 fps
12.5 gr 1,610 fps

 

[Jason_W]

Cool test, but it looks like you posted the same vid twice.

Gelatin can be really frustrating stuff to work with. My dream is to some day purchase an ample supply of this stuff

http://clearballistics.com/

 

[PedalBiker]

I recently read an article about Hornady using "ballistic" soap.

 

[Jason_W]

Also called Swedish soap, that's the preferred test medium in a lot of European nations. It's not as good a tissue simulant due to the lack of elasticity.

 

[chopinbloc]

Cool test, but it looks like you posted the same vid twice.

Gelatin can be really frustrating stuff to work with. My dream is to some day purchase an ample supply of this stuff

http://clearballistics.com/

Sorry about that. It's fixed now. I haven't worked with Cleargel at all but from the looks of it, it's a lot more convenient. Unfortunately, there appear to be substantial discrepancies between real gelatin and Cleargel at velocities starting around 1,200-1,300 fps and the discrepancy increases as the velocity increases. I could be mistaken, but in comparing my own, admittedly unprofessional, tests as well as other real calibrated gelatin tests against Cleargel, it seems that Cleargel is a good approximation at "normal" service pistol velocities but can produce misleading results at magnum handgun or rifle velocities. For that reason, I choose to stay with gelatin.

Here's one example of the discrepancy I'm talking about. The first video is done by mrgunsngear (great channel, BTW). The second video is my own. While the ammunition is different, the bullet and resultant velocity are the same so performance should be nearly identical. It is possible that the variation is a normal variation that would be apparent if a statistically relevant sample size were created, but the degree of variation makes that unlikely in my opinion.




Average velocity: 2,331 fps
Penetration: 25.1"
Retained weight: 115 gr
Average expansion: 0.54"




123 gr Hornady SST loaded over 25.2 grains of Hodgdon H4198 and fired from a Norinco SKS (21" bbl) into calibrated gelatin.

BB calibration: 609.3 3.7"

Impact velocity: 2,284 fps
Penetration: 16.7"
Retained weight: 77.0 gr
Max expansion: 0.583"
Min expansion: 0.412"


That is a foot of difference in penetration. Easily enough to cause a person to decide to forgo this ammunition for home defense if they were to rely only on the Cleargel result. I'm really not trying to bag on the work other amateurs are doing. I'm grateful that it's being done. I just want to ensure the best accuracy we can reasonably achieve. If anyone knows of some data that supports or disproves that discrepancy, I'd really like to see it.

 

[Jason_W]

Wow, the .44 mag from a carbine is a real beast at close ranges.

Admittedly, results obtained from cleargel and other synthetic gels can't be compared to those obtained from organic gelatin, but it should work for the comparative testing I like to to (ex. .44 mag v. .30-30 in the same media at X yards).

The fact that the stuff is indefinitely reusable and very photogenic is a big selling point as well. Too bad the up front cost is so high.

 

[chopinbloc]

I'm not sure it's even that useful for head to head comparisons, at least not in any practical way. Even when we are simply comparing one load to another, we are looking to see how they perform relative to each other in tissue. We may not expect a perfect prediction of behavior in tissue (gelatin can't predict the behavior of projectiles after striking bone) but even when comparing projectiles only to each other, the comparison is still relative to tissue. In your example, the velocity difference between .44 mag and .30-30 is enough that the comparison is likely to be invalid in Cleargel or water. If you were comparing one .44 projectile to another at similar velocity, it might provide some insight, even if it did not produce an accurate model of performance in the real world. At that rate, though, water is nearly free and can give rough comparisons as well. It can even get close to an approximation of penetration depth if you account for the velocity.

 

[Jason_W]

According to the cleargel website FAQ, they make the claim that their product 100% replaced 10 or 20 percent gelatin calibrated to FBI standards. IIRC, It was permagel that differed somewhat from organic gel.

Without doing a side by side test, it's hard to say if anyone is telling the truth. It certainly would be nice to use a block of expensive test media more than once.

 

[chopinbloc]

I reuse the gelatin. It's a little more labor intensive than the Cleargel product, I think, but I just put it in a double boiler* and remelt it after I'm done taking photos. I then pour it through a course mesh strainer and then a fine wire mesh coffee filter. After a few dozen uses it gets too opaque to be useful but it appears it can be reused almost indefinitely so long as it doesn't spoil. That's the real advantage of the Cleargel: it doesn't require refrigeration and has a much wider temperature range.

The point of using heterogeneous test media is that you don't need to do a side by side comparison. The media should produce consistent results if the test conditions are conscientiously duplicated. If a load tested in Cleargel differs from real gelatin that was properly calibrated, then the Cleargel is not producing accurate results.

I believe that their claim that the media is consistent is accurate within the scope of the 590 fps .177 calibration BB and 600-1,100 fps service pistol cartridges or 12ga shot. It's not so much that they are lying, it's just that I don't think that media is really intended to be used for modeling the behavior of magnum handgun rounds or rifle rounds in tissue. We can settle the problem pretty easily by finding comparisons of real, properly calibrated gelatin tests to Cleargel tests where the same projectile is used at a similar velocity. I only know of a few such cases. If you guys can help find comparisons, I'd really appreciate it. I would prefer to work with Cleargel if we can demonstrate that it is accurate.







*actually a plastic bucket in a big stock pot

 

[Jason_W]

Interesting. I always thought that the molecular bonds of organic gelatin break down every time you melt and re-cast. Since you're calibrating for every test, it would seem that notion is false.

I would love to do a side by side comparison of cleargel to calibrated organic gel. My current circumstances prohibit that, unfortunately.

 

[chopinbloc]

You could be right. Maybe it takes more melt cycles or higher temperature or longer exposure to high temperature or some combination of those factors for the effect to be noticeable. I'm certainly no expert but I did stay at a Holliday Inn Express once.

 

[Jason_W]

You could be right. Maybe it takes more melt cycles or higher temperature or longer exposure to high temperature or some combination of those factors for the effect to be noticeable. I'm certainly no expert but I did stay at a Holliday Inn Express once.

That happens once every few years.

Hair splitting aside, terminal performance tests, even of the backyard variety are interesting. Keep up the good work.

 

[chopinbloc]

I agree. Thank you.