Bullet testing in ballistic gel

[theboondoogle]

First post here on Rokslide, so I thought I'd make it an interesting one. I've been posting this info on a few other forums, but it was suggested that I throw it up here as well.

I've done a lot of bullet testing over the years using different materials and methods to catch bullets. A few years ago I did a pretty lengthy test using leather apron scraps (similar to thick suede leather) soaked in water. I tested a total of 83 bullets ranging from 85gr 6mm bullets out of an 18" 6mm BR, up through 500gr Hornady RN bullets from a 458 Arnold (458 Lott variant). Most of the pictures from that testing were posted up on a thread over on LRH but were lost during a "mishap" with Photobucket. It's been a few years and I decided to bring back the testing and switch to ballistic gel this time around. The testing is much slower using the gel and I'm finding that it's much harder to capture the bullets. The upside is that I'm able to get a video of the impacts, which I'm editing down into short clips with both full-speed and slow-motion clips of every bullet I test.

The basic testing is the same for each bullet. I try to decide on an impact velocity that I want to test, then figure out which gun will do that best. For the bullets that I shoot on a regular basis, this is pretty easy. For the rest of the bullets I typically only have 5-10 samples available to find a load with the correct velocity, figure out where they're hitting, and manage to hit the 6" block while getting it on video. Since part of this testing has been trying to see the difference in bullet performance relative to bullet stability, I can't just download the ammunition to match the velocity I want because that could negatively impact the stability of the bullet. Basically, I'm making excuses for some of the really marginal hits I've made on the gel block! LOL

I'm going to break this up into a few different posts just to make it easier to sort through. I'll also throw it out there that there are a lot of bullets from Hammer Bullets included in the tests. This is primarily because that's just the hunting bullet that I use the most. In fact, I load them in 12 different chamberings. I'm not plugging their bullets and I've actually seen some interesting trends with the ones I have shot into the gel so far. I came into this testing with an open mind and I'd love to hear everyone else's thoughts and interpretations of what they see here.

With all that out of the way, here's the first round of testing with a 375 Ruger:

This is a 375 Ruger testing the 275gr Sledge Hammer, 300gr Partition, and 260gr Accubond. The 260gr Accubond was my go to load for nearly 10 years before getting replaced by the 275gr Sledge Hammer. I use the 300gr Partitions for practice and plinking.

Muzzle velocities:
275gr Sledge Hammer : 2655 fps
300gr Partition: 2515 fps
260gr Partition: 2760 fps

The first shot with the 275gr Sledge Hammer went a little high, but not so high that I needed to redo the shot. The bullet penetrated 32" of 20% ballistic gel at 150 yards and exited the blocks. I don't know how far it would have continued to penetrate, but it didn't show any signs of slowing down! The second shot was a 300gr Partition that penetrated 30.5". The third shot was a 260gr Accubond which impacted too high and exited the gel. I fired a second shot which penetrated 25" of gel.

275gr Sledge Hammer

300gr Partition

260gr Accubond #1

260gr Accubond #2

 

[theboondoogle]

7mm SAUM bullet testing

This is the first round of 7mm bullets shot at 200 yards from a 1-8.5" twist 7mm SAUM. I only had a few of the 143 HH and 155 CE MTH bullets left, so I thought I could do this without any sighters, I was wrong and they were hitting pretty high. I was already zeroed at 200 yards with the 165 TGK, so those were dead on.

Here are the muzzle velocities of the loads tested.

143 HH: 3142 fps
155 MTH: 2955 fps
165 TGK: 2960 fps

Here's the first shot with the 143 HH

Second 143 HH

155 Cutting Edge MTH

165 Tipped Game King

The Hammer and CE bullets just didn't want to stay in the block with all three of those bullets exiting by either curving up (Hammers) or out the side (Cutting Edge). The Sierra bullet did stay in the gel and penetrated 19.5". I haven't had time to dig the bullet out and weigh it, but it held up pretty well considering the relatively high impact velocity.

The 143 HH shed about 6 petals which all exited either the top or sides of the block. The MTH left large fragments, most of which stayed in the block.

 

[B23]

Feel like testing some Atips in gel I'll send you a few more.

 

[theboondoogle]

High velocity 270 bullet tests. These were all fired from a 1:8.5" twist 270/338 RUM wildcat. The approximate impact velocities are written on the gel blocks.

117gr HH
impact velocity 3750fps

- 30.5" Total average penetration for 3 shots
- weight of the recovered bullet shank 89.8gr

156gr HH
impact velocity 3280fps

- 30" penetration before exiting the top of the block
addition testing will be done to measure actual penetration.

170gr Berger EOL
impact velocity 3120fps

- 24" penetration of the largest bullet fragment.
- The largest recovered bullet fragment weighed 23.2gr, the rest of the bullet broke up into tiny pieces.

140gr Sierra TGK (Gamechanger)
impact velocity 3360fps

- 14.5" total penetration.
- The largest recovered bullet fragment weight 39.4gr. The rest of the bullet broke up into tiny pieces.

 

[Formidilosus]

use the 300gr The bullet penetrated 32" of 20% ballistic gel

As 20% ballistics gel has little to no correlation to tissue, and the data base certainly isn’t there for comparisons, why did you choose to use it? Also, how are you calibrating the gel?

 

[theboondoogle]

Feel like testing some Atips in gel I'll send you a few more.

I might still have two left from the others you sent me! LOL I'll see if I can find them.

As 20% ballistics gel has little to no correlation to tissue, and the data base certainly isn’t there for comparisons, why did you choose to use it? Also, how are you calibrating the gel?

I'm glad you mentioned the 20% gel. The 375s are actually the only bullets tested in the 20% gel, The rest are all fired into a 10% block in the front and the 20% blocks are used to capture the bullets. The only reason I switched to 10% is that's what was on sale when I needed to buy more gel. I should have made that more clear.

To the point about 20% gel having little no correlation to tissue, 10% gel has little to no correlation to an actual animal. An animal isn't a homogeneous mass with a consistent or calibrated density. 10% gel is just as arbitrary as wet newspapers or blocks of modeling clay. Gel doesn't account for hair, hide bone, fat, partially digested food, or any other material in an animal besides muscle. One reason my early tests were done with 20% gel is because that's what I had on hand. The other reason I started with 20% gel is that I wanted to limit penetration so I didn't need to line up 60" of gel to catch the bullets. I've shot the same loads into both 20% and 10% gel and the difference in penetration was less than 15% and there was no meaningful difference in bullet expansion or performance. The variations I've seen in 10% vs 20% gel are not significantly different than the shot to shot variations I see shooting the same load into the same target in a span of 5 minutes.

As far as calibrating the gel, every block comes with a calibration certificate from Clear Ballistics. I suppose I could dig them out and include the Lot # and a copy of the certificate with each test. I could also do a calibration test by firing a .177 BB at 590fps into every block. That seems really unnecessary though. If These tests were intended to be anything more than just a fun experiment, then that's exactly what I would do. Fortunately, I'm not getting paid to do this and it's completely unscientific, so calibration really doesn't matter.

 

[theboondoogle]

More testing, but with 338 bullets this time. All bullets were fired from an 18" barreled 338/375 Ruger specialty pistol. You'll have to excuse the "champagne gel block" thing that I have going on with a few of the blocks. I was short on time and didn't have time to throw the gel blocks in the oven after dumping the gel in the mold. That lets air bubbles get trapped in the gel. The approximate impact velocities and retained bullet weight are written on the gel blocks, with the exception of the 285gr ELDm, I spaced and wrote the wrong velocity on that one and it should be 2570 fps, not the 2270 on the block.

The test line up from this trip out: 225 TTSX, 250gr SB II, 260gr Hammer Hunter, 270gr SB I, 285gr ELDm

225gr TTSX

This bullet exited the gel at roughly 35" of penetration. It appears in the video that the bullet had slowed down dramatically by the time it exited the gel, so I don't imagine it would have traveled much farther. I also assumed that it looked like every other TTSX bullet I've recovered, so it didn't seem necessary to shoot additional rounds to try and recover a bullet.

250gr SB II

This bullet surprised me with it's relatively shallow penetration of 24.5". The damage appears substantial though and the weight retention was very good. I didn't know going into this that the SuperBuldozers are intended to retain the majority of their weight and not necessarily shed petals. With that in mind, the bullet appears to have performed exactly how it should have.

260gr Hammer Hunter

The first bullet I fired exited the side of the second block at about 27". I fired a second bullet into the gel later on, which was recovered at 36.5". Performance was consistent with all the other Hammers I've shot

270gr SB I

The 270 SuperBuldozer I penetrated 27.5" before exiting the side of the block on the first shot and a second bullet was recovered at 37" of penetration. I was really impressed with the penetration of this bullet at the low impact velocity.

285gr ELDm

The recovered 285 ELDm weighed 160.4gr and penetrated 18.5". Lead core bullets give some of the most spectacular impacts in the gel! LOL Penetration wasn't very impressive, but I have to assume that this bullet would have really done a number on anything it hit. Expansion and weight retention were perfectly in line with all the other ELDm and ELDx bullets I've tested.

 

[Formidilosus]

To the point about 20% gel having little no correlation to tissue, 10% gel has little to no correlation to an actual animal. An animal isn't a homogeneous mass with a consistent or calibrated density. 10% gel is just as arbitrary as wet newspapers or blocks of modeling clay. Gel doesn't account for hair, hide bone, fat, partially digested food, or any other material in an animal besides muscle.

Properly calibrated, 10% organic ballistics gel has shown a relatively high correlation to expectation in tissue and with certain portions of the FBI protocol, very good extrapolation.

Within 10% of any metric to this-

Bare gel- pure rib shots

Heavy denim- ribs shots with think hide (moose, etc)

Ply wood- scapula shots

Glass- The “knuckle” of the joint from the scapula and humerus.


What you’re doing is great, but unfortunately is going to give false information other than pictures of bullets. Clear ballistics gel has consistently proven to not be a reliable indicator of what bullets son in tissue, and bullets behave differently in it than in tissue (or 10% organic gel).

 

[Formidilosus]

To be clear, I’m not trying to sharpshoot what you’re doing. Just that with the effort you’re going through already, doing it the best way isn’t much harder and results are better.

 

[theboondoogle]

Properly calibrated, 10% organic ballistics gel has shown a relatively high correlation to expectation in tissue and with certain portions of the FBI protocol, very good extrapolation.

Within 10% of any metric to this-

Bare gel- pure rib shots

Heavy denim- ribs shots with think hide (moose, etc)

Ply wood- scapula shots

Glass- The “knuckle” of the joint from the scapula and humerus.


What you’re doing is great, but unfortunately is going to give false information other than pictures of bullets. Clear ballistics gel has consistently proven to not be a reliable indicator of what bullets son in tissue, and bullets behave differently in it than in tissue (or 10% organic gel).

I understand and agree with all of that. But, working with organic gel has additional complications and considerations which I just have no interest in dealing with. The organic gel needs to be kept at a controlled temperature, which is something I don't have space for. Organic gel is more susceptible to contamination, which is something I just don't want to worry about. The synthetic gel is easier to work with and easier to store. When I need more, I just call up Clear Ballistics to place an order and it magically shows up on my doorstep 7 days and about $60 later. The synthetic gel is also a lot easier to reclaim, I just throw it into the crockpot and let it melt down overnight.

The best thing I can really tell you is to just lower your expectations. This is just a fun way to waste time and burn up components.

 

[Okie_Poke]

What you’re doing is great, but unfortunately is going to give false information other than pictures of bullets. Clear ballistics gel has consistently proven to not be a reliable indicator of what bullets son in tissue, and bullets behave differently in it than in tissue (or 10% organic gel).

I know I'm necroing an old thread, but a couple of Form's recentish podcasts about bullet selection and terminal ballstics have me googling around about these topics, and this thread popped up on the google machine.

I get that Clear Ballistics gel is not identical to properly calibrated 10% organic ordinance gel, and it's my understanding that 10% organic gel is the best test medium we have to test how bullets behave in animals. So, comparing test results in Clear Ballistics gel to published, scientific results in organic gel is like comparing apples-to-oranges.

But . . . why does that make Clear Ballistics gel useless for showing anything other than pictures of bullets? Is Clear Ballistics gel too inconsistent from batch-to-batch or block-to-block to compare bullets shot in Clear Ballistics gel against each other on an apples-to-apples basis? When you say bullets behave differently in synthetic gel than organic gel, what do you mean? Is it just that the raw penetration and expansion numbers are different (e.g., bullets tend to penetrate less but expand more in organic gel), or is there a difference in kind here (e.g., the wound cavities are drastically different shapes and the bullets upset in completely different ways, or something like that)?

I'll use a hypothetical. Suppose I want to compare how a 180 grain Accubond from my 30-06 compares to a 143 ELD-X from my 6.5 Creedmoor. If I shoot them both into synthetic gel, is that really not going to tell me anything other than what the bullets look like after expansion in that medium? If one penetrates more than the other, can I not conclude that bullet will likely penetrate more than the other in an animal (even if how much it penetrates in an animal is not the same as in the gel)? Similarly, if one creates a larger and more explosive wound channel in synthetic gel, will that bullet not also create a larger wound channel than the other in an animal (even if the actual size of wound in the animal is different than it is in the gel)?

Thanks in advance for your patience and explanation.

 

[Formidilosus]

Is Clear Ballistics gel too inconsistent from batch-to-batch or block-to-block to compare bullets shot in Clear Ballistics gel against each other on an apples-to-apples basis?

Yes.

When you say bullets behave differently in synthetic gel than organic gel, what do you mean? Is it just that the raw penetration and expansion numbers are different

Yes.

(e.g., bullets tend to penetrate less but expand more in organic gel), or is there a difference in kind here (e.g., the wound cavities are drastically different shapes and the bullets upset in completely different ways, or something like that)?

And yes, if the enough they are.

I'll use a hypothetical. Suppose I want to compare how a 180 grain Accubond from my 30-06 compares to a 143 ELD-X from my 6.5 Creedmoor. If I shoot them both into synthetic gel, is that really not going to tell me anything other than what the bullets look like after expansion in that medium? If one penetrates more than the other, can I not conclude that bullet will likely penetrate more than the other in an animal (even if how much it penetrates in an animal is not the same as in the gel)?

To an extent that will show. But water jugs would show the same.

Similarly, if one creates a larger and more explosive wound channel in synthetic gel, will that bullet not also create a larger wound channel than the other in an animal (even if the actual size of wound in the animal is different than it is in the gel)?

Yes and no. The issue is clear ballistics gel is variable from block to block. You could get about as much, or close, to the same info comparing two bullets in clear synthetic gel as you could wet newspaper and water.

 

[Okie_Poke]

Thanks, @Formidilosus.