Gelatin tests: 9mm COR BON 100 gr +P & .44 mag Underwood 180 gr XTP

[chopinbloc]

9mm COR BON 100 gr +P fired from Glock 22 with Lone Wolf 9mm conversion barrel through four layers of denim into calibrated gelatin.

BB: 579.8 fps, 3.7"

Impact velocity: 1,495 fps
Penetration: 13.1"
Retained weight: 98.9 gr
Max expansion: 0.587"
Min expansion: 0.553"

The plastic ball was at about 3.5" and weighed 1.9 gr.





.44 mag Underwood 180 gr XTP fired from 6" Herter's SA through four layers of denim into calibrated gelatin.

BB: 579.8 fps, 3.7"

Impact velocity: 1,663 fps
Penetration: 11.8"
Retained weight: 154.7 gr
Max expansion: 0.945"
Min expansion: 0.582"

The bullet exited the first block and bounced off the second block. If you look closely you can see it on the table just before the block lands on it.

 

[willypete]

Those results are both very interesting. Thank you for doing this test. I would have expected the .44 Mag to penetrate more and the 9mm to penetrate less.

 

[Nickb45]

496 ft-lbs vs 1135 ft-lbs.

The energy difference showed in how much the gel moved.

 

[Sam Cade]

Agreed with willypete. I would have expected the 9mm to completely discombobulate early despite the plugging effect of the denim.

I guess the Ball works.

 

[chopinbloc]

I concur. I expected the same.

 

[Shawn Dodson]

The plastic sphere in the hollow cavity of the Pow'RBall bullet inhibits expansion which allows it to penetrate deeper than one would expect. The downside of Pow'RBall is its poor penetration performance thru windshield glass.

 

[chopinbloc]

Yeah, that's a lot deeper than you would expect from a 100 gr 9mm. Still, the late expansion isn't exactly a good thing. 124 gr HST, Gold Dot, and Ranger T are still the best choices in 9mm with everything else WAY behind.

 

[2zulu1]

Both penetrated deeper than I expected. What was the temperature of the gelatin at bullet impact? Was the gelatin 10% ordnance gelatin?

Hornady publishes the velocity design windows for their XTPs, the velocity design window for the .429cal 180gr XTP is 750fps-1400fps. It appears Underwood loaded the 180gr XTP for the caliber rather than the bullet.

FWIW, one can use water to screen bullet performance, saving time and $$$s.
Also, calibration for 10% ballistic gelatin is 590fps/8.5cm @4°C, the tested BB velocity/penetration are within +/- parameters.

Very nice test, thanks for sharing.

 

[chopinbloc]

Thank you for the compliment and thanks for looking.

590 fps +/- 15 fps, 2.95"-3.74" is the calibration rang, I believe. There is also a table for correcting penetration for blocks that calibrate slightly out of range but there is some disagreement on the validity of those corrections.

I keep my refrigerator at 39 degrees F as measured by a thermometer right on top of the gel. I keep the gelatin in a cooler until immediately before the test and I do the calibration shot right before the test shot. My tests are not done under controlled laboratory conditions and I don't shoot a statistically relevant sample size but I do strive to meet standards as much as is feasible. I believe that my tests are generally accurate. In other words, I try to do as well as is reasonable for an informal test conducted by a layman in field conditions.

Water only provides a very general idea of performance and tends to show maximum possible bullet upset. It also is wildly inaccurate in regards to penetration for higher velocity projectiles.

 

[Shawn Dodson]

In other words, I try to do as well as is reasonable for an informal test conducted by a layman in field conditions.

I think you do a superb job!

 

[chopinbloc]

Shawn Dodson, thank you. That really does mean a lot, especially from you.

2zulu1, found the table:

As you can see, there is virtually no correction advised for blocks that calibrate in range and the maximum adjustment is one centimeter. It seems to me that anything that is reasonably close ought to yield a result that is likewise close to actual performance. Not that I intend to use that as an excuse to relax my standards.

I forgot to mention last night that while I do strive to keep the blocks as close to 39 degrees F as possible, I think the BB calibration result is much more important than the temperature.

I also neglected to answer your question about the gelatin. Yes, it is 10% but it is grocery store food gelatin. This is what Vyse has to say about food gelatin:

This is a measure of gel strength. This is critical! If the bloom strength is off your results will be as well. Bloom is measured on a Texture Analyzer. 250 Bloom is the standard, however, a typical food specification is ± 10 grams. This is great for a gelatin dessert or candy, but not for ballistics testing. We have narrowed that down to 250 ± 5 grams.

(from: http://www.gelatininnovations.com/pages/ballistic.html

While it is probably of some importance, I doubt that it is as important as they make it out to be, so long as the block calibrates correctly. I do plan to just pony up and buy the real stuff eventually.