Questions about the irrelevance of energy (ft-lbs)

[BigEd36]

I jumped out of this thread cause it jumped the shark.

For anyone genuinely trying to sort through this stuff, Stinky Coyote is WAY too interested in some numbers to quantify things and he is unnecessarily complicating the issue…

I am not addressing him because I won’t respond to his convoluted rants. This is for anyone confused by him.

His premise is that we need a number and complex model to predict what a bullet does in tissue. He repeatedly compares terminal ballistics to ballistic flight computations and modeling. Even suggesting that a few more fields could add numbers he wants.

The problem with his approach is that he consistently fails to acknowledge what we actually know—while complaining about what we don’t have.

We have proof as plain as the pictures Form posted. But, Stinky wants numbers spit out by a terminal ballistic calculator so he can see a number attached to it.

As hunters, do we actually need numbers and a field in a ballistic calculator?

Bottom line for known highly fragmenting bullets is put them inside the vitals at least 1800 fps and it will result in lethal wounding with significant tissue damage.

There is idea that, we don’t see bullet failures is because they live—so we can’t know. That is a good question to ask, but it has been thoroughly disproven with the testing that shows incredibly consistent performance with no failures in proper gel.

If you need more than what is out there with actual FBI gel testing and confirmed in hundreds if not thousands of pictures of dead critters— you might be the kind who needs proof the moon isn’t actually cheese.

Like Form says, there is no debate about the facts anymore. Stinky is making this about numbers that he wants as proof of what we know the facts to be.

Those are two different things entirely.

 

[Stinky Coyote]

I jumped out of this thread cause it jumped the shark.

For anyone genuinely trying to sort through this stuff, Stinky Coyote is WAY too interested in some numbers to quantify things and he is unnecessarily complicating the issue…

I am not addressing him because I won’t respond to his convoluted rants. This is for anyone confused by him.

His premise is that we need a number and complex model to predict what a bullet does in tissue. He repeatedly compares terminal ballistics to ballistic flight computations and modeling. Even suggesting that a few more fields could add numbers he wants.

The problem with his approach is that he consistently fails to acknowledge what we actually know—while complaining about what we don’t have.

We have proof as plain as the pictures Form posted. But, Stinky wants numbers spit out by a terminal ballistic calculator so he can see a number attached to it.

As hunters, do we actually need numbers and a field in a ballistic calculator?

Bottom line for known highly fragmenting bullets is put them inside the vitals at least 1800 fps and it will result in lethal wounding with significant tissue damage.

There is idea that, we don’t see bullet failures is because they live—so we can’t know. That is a good question to ask, but it has been thoroughly disproven with the testing that shows incredibly consistent performance with no failures in proper gel.

If you need more than what is out there with actual FBI gel testing and confirmed in hundreds if not thousands of pictures of dead critters— you might be the kind who needs proof the moon isn’t actually cheese.

Like Form says, there is no debate about the facts anymore. Stinky is making this about numbers that he wants as proof of what we know the facts to be.

Those are two different things entirely.

Just a couple corrections to that.

1. I don't want a number to spit out of a calculator for me, but for all hunters. I can math out differences to satisfy myself no prob and was well ahead of the curve on understanding the subjectivity of terminal ballistics and what I need to use for what I do and game intended.

2. No, we don't know and don't have. We only partially know some of the story at one impact velocity point.

3. Proof of death is not required, it's death. Shades of death by subjective imagination from single point incomplete data set of one specific impact velocity to emulate and compare to all ranges against other bullets we don't have capability yet.

4. This isn't about 'needing' more, it's about 'wanting' more. So everyone can play along nicely rather than page after page, thread after thread, year after year of the same subjective shades of death discussions.

5. This isn't about modelling what a bullet does in tissue lol. It's about modelling what 'work' a bullet transfers over what distance in a standard (to represent tissue), at all fps from muzzle to where it does nothing but poke a hole at whatever distance that may be.

6. Yes we are talking about 2 different things lol.

7. And 1800 fps is good for you? with what bullet or bullet family? Why? Lol - here comes the subjective train again. 1600 fps might be what another guy wants and different bullet family. Be nice to see the expected work transfer over how many inches wouldn't it? Quick easy numbers, hardly an imagination required as you can compare to anything else we already know gives the shade of death we personally prefer from drt to 100 yard eat to the hole recoveries. Maybe you want to only hunt big stuff to 300 yards and want to compare a bunch of stuff that has usable life at triple the distances? And fine tune your selections for your goals intended and find value in bullets you hadn't considered for that particular desire/application? We tend to focus on the best bullets for drt performance and the furthest ranges here...what I'm talking about would help everyone that does everything but that. Africa, Varmints, short range, mid range, long range etc.

 

[hereinaz]

Thanks for thoughts. Your points on fbi calibrated gel are clearly right. And doing some research, the other options that retain the shape and size of representative wound cavity wouldnt save much time or money in any event. So fbi gel it is.

My idea of simplifying the size of wound cavity and penetration to a “rating” metric is simply to try to create something that would be easily and quickly communicated to a larger audience. Similar to the dumb silhouettes of game animals that bullet makers place on their ammo boxes to guide hunters to correct choices. While those are horsepucky and miss-leading, I was thinking the “metric” would be 1000 times more accurate and honest.

Based on your input, sounds like a bad idea. Its just as easy in the end to put real dimensions in a bullet rating system— something like Wound Size- 18.5 cubic inches, Penetration- 14.5 inches. Shorten it to WS18.5cu” P14.5” and its easy to understand and tied to actual terminal performance.

In the end of the day that is a minor detail to the giant elephant in room which is cost to do this testing per bullet. Especially when one realizes that every weight / caliber of every bullet has to go through the entire test protocol. Even at just $100 per gel block test thats 3k for each bullet tested. And I expect that is low.

More Random questions:

1- do you know if labs doing this work re-melt and re-use gel? I see conflicting info on-line.

2- does neck distance change enough between various hunting bullets to be worth measuring and tracking? Seems like a bullet is either expanding in the first 1-2” or its not suitable as a hunting bullet. But am I missing a use -case or a performance difference that makes this an important metric to track and compare?

Thanks,

Dag

As to reusing FBI gellatin, no you can’t remelt it.

Gellatin is actually nothing more than jello without the sugar and coloring. You make FBI gel just like jello.

To use gel it has to be made correctly and refrigerated until used. It would be a process to make and store it, which is why I haven’t done any tests. I almost bought the fake stuff, until I realized it was not a valid medium.

10% gellatin tells you it is 90% water 10% gellatin powder. The more water you use the less firm it is. The reason it can simulate tissue is because it has the water content.

The fake clear gel that is melted and reused has no water content. The many “long range” gel “tests” on YouTube showing bullets fail at known velocities like 2000 fps are absolutely useless because it has no water. That’s why I pay little attention to YT videos cause they are either ignorant or purposely misleading.

 

[Harvey_NW]

Pretty bullet = not much damage.
Kind of ugly bullet = moderate damage.
Ugly mangled remnants of bullet = big damage.

This is genius level stuff, do your best to understand what you can

 

[Bluefish]

We have proof as plain as the pictures Form posted. But, Stinky wants numbers spit out by a terminal ballistic calculator so he can see a number attached to it.

As hunters, do we actually need numbers and a field in a ballistic calculator?

Bottom line for known highly fragmenting bullets is put them inside the vitals at least 1800 fps and it will result in lethal wounding with significant tissue damage.

I am a believer that use a fragmenting, heavy for caliber bullet in the vitals and it’s going to die. Now as an engineer I can see the advantage of having something measurable to compare bullets. It would be interesting to have an energy/linear measurement and a total penetration. With those two things I could compare different bullets and/or different animal. Even just a penetration in gel for any given bullet on the box. What we get is marketing, ie want penetration get a copper or solid of some sort. Well, how much difference does that really make? Are we talking 30” of gel vs 18”? Or 24” vs 18”? Don’t know as it’s not published. If we had such numbers, you could also show that a 30 cal partition is similar on game to a 223 77tmk. Then it’s no longer an argument, ie the manufacturer just said they perform the same.

Also not everyone can use heavy fragmenting bullets, due to lead free regulations, cartridge choices, personal choice, or manufactures not making them in all calibers. So how do you achieve similar results with other options? With no metrics to measure performance how would you know, other than killing lots of animals. That’s simply not feasible for me. I might get 1-3 deer per year. I may hunt another 15 years, so I will kill less in my like than some will in a year. That’s not very many test cases.

Having quantifiable potential wounding data would really upend the dogma about what you need to use to hunt. Unfortunately most hunters don’t care that much and it could take 15-20 years for it to become the new standard.

 

[Stinky Coyote]

In time the modelling would move beyond linear for the energy vs travel. Certain families will dump more at certain impact velocity nodes in the front end than others and could be a ratio that shows it? A percentage perhaps, of energy vs vs initial travel depth etc. 2/3 energy in first half of travel and 1/3rd in last half for match say, the bonded and monos likely far more linear. We can visualize it but zero objective data to support it.

There are so many possibilities at how far this could go in usefulness for hunters, and manufacturers too (product development). No different than how far things have come in inflight ballistics development with everyone using radar now and seeing nodes of bc change etc. Allowing more accurate solutions at further and further distances.

We haven’t even started walking on this yet. We are lacking vision and ability to kick the can down the road. We’re barely starting to ask the right questions.

 

[Axlrod]

I jumped out of this thread cause it jumped the shark.

For anyone genuinely trying to sort through this stuff, Stinky Coyote is WAY too interested in some numbers to quantify things and he is unnecessarily complicating the issue…

I am not addressing him because I won’t respond to his convoluted rants. This is for anyone confused by him.

His premise is that we need a number and complex model to predict what a bullet does in tissue. He repeatedly compares terminal ballistics to ballistic flight computations and modeling. Even suggesting that a few more fields could add numbers he wants.

The problem with his approach is that he consistently fails to acknowledge what we actually know—while complaining about what we don’t have.

We have proof as plain as the pictures Form posted. But, Stinky wants numbers spit out by a terminal ballistic calculator so he can see a number attached to it.

As hunters, do we actually need numbers and a field in a ballistic calculator?

Bottom line for known highly fragmenting bullets is put them inside the vitals at least 1800 fps and it will result in lethal wounding with significant tissue damage.

There is idea that, we don’t see bullet failures is because they live—so we can’t know. That is a good question to ask, but it has been thoroughly disproven with the testing that shows incredibly consistent performance with no failures in proper gel.

If you need more than what is out there with actual FBI gel testing and confirmed in hundreds if not thousands of pictures of dead critters— you might be the kind who needs proof the moon isn’t actually cheese.

Like Form says, there is no debate about the facts anymore. Stinky is making this about numbers that he wants as proof of what we know the facts to be.

Those are two different things entirely.

At the ranch when I was a boy, there was a bridge across an irrigation canal that went to the highway. In order to keep us kids away from the canal and highway, my grandmother told us there was a troll living under the bridge. She warned us to stay away from the troll. Grandma's advice should always be heeded! Stay away from the troll.

 

[HandgunHTR]

I do this for living, look at the numbers and make useful for my team, for the goals of my team. And I got lucky to get a job that works for my mind like that. Make it easy, make it fast, create calculators and useful way to see and use the data.

You look at project data and $$ and create spreadsheets so that you can understand if the project is going well or not. That is a very long cry from looking at physical data and back-calculating the actual physics involved. You may think you have this "figured out", but again I say. You are not even close because you lack a fundamental understanding of the physics at play. Your continued focus on energy and work proves this.

Running an 800 yard comparison between bullets, running a 1600 fps comparison between bullets, and seeing expected rates of change and work transfer etc. We look at basic info at one impact velocity and I mean basic. Like mid 20th century basic.

Please explain this "work transfer" term you continue to use.

I've demonstrated this is possible.

You have not demonstrated anything. You have proposed a solution to a problem that has already been solved (multiple times) by physical evidence.

We know the bullet will drop less work over greater inches as the yardage increases as it's rate of change slows, but currently in inflight ballistic calculators we get enough data to see what the bullet lands with for energy and it's starting sd and that's it, you get to imagine the rate of change and transfer load and penetration distance from there.

You continue to show your complete lack of understanding. "Drop less work"??? What the hell does that even mean. You are using work and energy interchangeably. They are categorically different things. It seems to me that you want energy to matter.
Say it with me boys and girls. When it comes to terminal ballistics, ENERGY DOESN'T FUKIN MATTER!!!!!

It wouldn't take that much to fill in the blanks with a few more numbers to make usable and comparable for all bullets we hunt with and get it to fill in the blanks every fps marker along the flight range to target and then show what to expect over the next 13-36" etc. You want the most work transfer over 14" at 800 yards? Run the calculator, run the bullet library, get your answers and top 5 choices....etc.

You mean energy transfer, don't you. I know you do.

 

[HandgunHTR]

In time the modelling would move beyond linear for the energy vs travel. Certain families will dump more at certain impact velocity nodes in the front end than others and could be a ratio that shows it? A percentage perhaps, of energy vs vs initial travel depth etc. 2/3 energy in first half of travel and 1/3rd in last half for match say, the bonded and monos likely far more linear. We can visualize it but zero objective data to support it.

So, you are saying that a frangible bullet would produce a larger permanent wound channel after the first 2-3 inches of penetration and then it would taper off as the bullet drives deeper, but a mono will have a smaller diameter wound channel that holds its shape for a longer time? That is a super cool theory. I bet would could do some super cool math to figure out what those average wound cavities would look like, huh?

Or, we could just reference the gel and animal tests that have already been performed and use the actual physical data.

There are so many possibilities at how far this could go in usefulness for hunters, and manufacturers too (product development). No different than how far things have come in inflight ballistics development with everyone using radar now and seeing nodes of bc change etc. Allowing more accurate solutions at further and further distances.

We haven’t even started walking on this yet. We are lacking vision and ability to kick the can down the road. We’re barely starting to ask the right questions.

You do realize that the math that we are using for in-flight ballistics has been around for about 150 years, right?

This "in-flight ballistics development" you speak of is nothing more than collecting PHYSICAL DATA and using it to check the math that we have been using because we didn't have the tools to collect the PHYSICAL DATA. Your radar example for instance. The use of radar is nothing more than using a new method to collect the PHYSICAL DATA to verify the math. Before radar, there were just a set of chronographs that were shot through. It's not that it wasn't being done, it is just that radar made it more effective and a touch more accurate.

There is no need to "do the math" if you already have the PHYSICAL DATA!

 

[DagOtto]

As to reusing FBI gellatin, no you can’t remelt it.

Gellatin is actually nothing more than jello without the sugar and coloring. You make FBI gel just like jello.

To use gel it has to be made correctly and refrigerated until used. It would be a process to make and store it, which is why I haven’t done any tests. I almost bought the fake stuff, until I realized it was not a valid medium.

10% gellatin tells you it is 90% water 10% gellatin powder. The more water you use the less firm it is. The reason it can simulate tissue is because it has the water content.

The fake clear gel that is melted and reused has no water content. The many “long range” gel “tests” on YouTube showing bullets fail at known velocities like 2000 fps are absolutely useless because it has no water. That’s why I pay little attention to YT videos cause they are either ignorant or purposely misleading.

Thanks, I came across reference that the FBI LE protocal allows for gel blocks to be impacted up to 5 times. One in a bit from
Each corner and one in the center, as long as no individual flight path crosses another.

Anybody have first hand knowledge of this? Obviously this would represent a massive savings although youd still want to do a single shot block of gel for the photo to be used as representative of that particular ammo.

 

[Formidilosus]

Thanks, I came across reference that the FBI LE protocal allows for gel blocks to be impacted up to 5 times. One in a bit from
Each corner and one in the center, as long as no individual flight path crosses another.

Anybody have first hand knowledge of this? Obviously this would represent a massive savings although youd still want to do a single shot block of gel for the photo to be used as representative of that particular ammo.

That is correct. But it’s also dependent on the damage created by the bullet. Clean gel blocks are shot to measure the total wounds through each barrier. Then, up to 4 more are shot into the block to measure consistency of upset and penetration depth.

 

[Stinky Coyote]

So, you are saying that a frangible bullet would produce a larger permanent wound channel after the first 2-3 inches of penetration and then it would taper off as the bullet drives deeper, but a mono will have a smaller diameter wound channel that holds its shape for a longer time? That is a super cool theory. I bet would could do some super cool math to figure out what those average wound cavities would look like, huh?

Or, we could just reference the gel and animal tests that have already been performed and use the actual physical data.



You do realize that the math that we are using for in-flight ballistics has been around for about 150 years, right?

This "in-flight ballistics development" you speak of is nothing more than collecting PHYSICAL DATA and using it to check the math that we have been using because we didn't have the tools to collect the PHYSICAL DATA. Your radar example for instance. The use of radar is nothing more than using a new method to collect the PHYSICAL DATA to verify the math. Before radar, there were just a set of chronographs that were shot through. It's not that it wasn't being done, it is just that radar made it more effective and a touch more accurate.

There is no need to "do the math" if you already have the PHYSICAL DATA!

Make your assumptions on what I say, if you can’t understand it doesn’t mean it isn’t understandable lol.

Model the swim flight however you like. We do a piss poor job of it now.

Don’t care if the ‘work’ is measured in psi, ft/lbs, kPa, kN, or some other ‘work’ unit of measure.

I don’t care if the outcome of work and speed of work of my 310hp/430 ft/lb truck engine(being more work at lower rpm) can tow a 12,000 lb trailer with different gearing up a certain grade. It comes with a standard tow rating for majority scenario. We can envision all it can do easily from there including what it might do in a lightweight sports car. In sports car application we may want less work but more speed of work than tyr truck engine example here, where i value more work at lower speed of work, as I tow a lot and use a truck as a truck.

It’s not the outcome of the work that is the worry. It will do the work. Shades of death still death. Model the work in work units over distance it works, in a standard and have every engine(bullet) have ratings or numbers to compare to all others. And then we can run every scenario we might imagine for that work potential. Deer at 800, elk at 600 and see if it’s a good fit for or preference of work. Drt or eat to hole...speed of work (hp) vs total work torque or ft/lbs. Do I want the 5.3 in my Chevy or the 2.7 turbo? Why do I like the turbo?

Cart before horse. We understand work being done but that’s about it. We don’t have a clear easy way to see the work load over the rpm range like in a motor. We have no Hp/torque curve to go with the peak hp and torque figures. We have impact velocity and initial ft/lbs.

Why aren’t we measuring the fps through the gel? Could you not measure that? And create a work curve from that alone?

Anyway. Understand what you can. I’ve tried my best to help you understand what is missing. The death part has been the focus. Modelling the work to get curves and standards and rates to objectify this has not been done yet and imo we are way behind. And because dead is dead we haven’t cared enough to go any further with it. We’ve cared more about getting dead to the target and therefor exponentially increased our ability to do so in terms of accuracy and distances. Our ability to choose shade of death we prefer is still rapid uncontrolled to controlled expansion vs delayed controlled expansion. That’s it. Subjective from there and no standard way to compare no standard curve data comes with bullets. And therefor no way for all of us to choose more accurate options for specific goals we have in mind. Long range guys just choose match bullets they can get to target at distance easier and know they open up easier to deliver what work is left better than bonded or monos. That’s it. Sad in 2025

 

[Lou270]

That is correct. But it’s also dependent on the damage created by the bullet. Clean gel blocks are shot to measure the total wounds through each barrier. Then, up to 4 more are shot into the block to measure consistency of upset and penetration depth.

Unless something very recently changed, wounds are not “measured” in FBI scoring. There is a 500 point scoring system based on penetration depth, bullet expansion, and weight retention. 70% of the scoring is based on penetration depth. Hornady and Black Hills and others like to publish other metrics like “wound cavity” diameter and depths of wound cavity to market their products, but the FBI protocol does not consider these metrics at all as Fackler et al, did not view the wounding of temporary cavity to be reliable and only considered crush cavity (ie expansion) in the scoring.

 

[Formidilosus]

Unless something very recently changed, wounds are not “measured” in FBI scoring. There is a 500 point scoring system based on penetration depth, bullet expansion, and weight retention. 70% of the scoring is based on penetration depth. Hornady and Black Hills and others like to publish other metrics like “wound cavity” diameter and depths of wound cavity to market their products, but the FBI protocol does not consider these metrics at all as Fackler et al, did not view the wounding of temporary cavity to be reliable and only considered crush cavity (ie expansion) in the scoring.

Is this from personal experience with the FBI and testing rifle projectiles?

 

[Lou270]

Is this from personal experience with the FBI and testing rifle projectiles?

No, but I am not sure what that has to do with anything. The FBI protocol is well known and published. People can research it themselves. If you are doing something else other than the scoring or adding your own metrics you are not following the standard

 

[Stinky Coyote]

So maybe the vehicle engine power curve model helps tie it together.

At every rpm we can see both the work(torque) and speed of work(hp). In objective numbers. Nothing to argue about.

Now how do we get that for terminal ballistics?

Distance travelled in gel is your rpm range. The torque curve total work potential and hp curve represented by the wounding you see (speed of work, gel or animal).

Is talking about that speed of work best done in inches of expected temporary/permanent wound damage outward circumference from bullet in a slice along that range? That’s like talking about the baseball player having low confidence because he has an ugly girlfriend. What’s his on base percentage? Lol

We have a long ways to go and need to change how we look at this.

The engine(bullet) output changes as it goes through the gel(both work and speed of work), measurable by sd and fps speed it’s travelling. We don’t measure that yet.

The data is there but we aren’t seeing how best to get it and put in usable form.

Since we like pictures here can someone throw up a typical dyno chart for a motor?

Do you like apples?

 

[Formidilosus]

No, but I am not sure what that has to do with anything.
The FBI protocol is well known and published. People can research it themselves. If you are doing something else other than the scoring or adding your own metrics you are not following the standard

Well, three things:

1). Where did I state that the scoring system the FBI uses is the best, or what should be done?

2). With rifle projectiles; the neck length, permanent crush cavity, temporary cavity, depth to temporary cavity, temporary cavity length, and total penetration is absolutely looked at and measured- depending on the bullet and purpose.

What do you believe the gridded board and measuring stick is for?









3). You are incorrect about Fackler and the temporary cavity with rifle projectiles. The TC can be variable, but absolutely can be a massive contributor to the wounding potential of a rifle projectile- especially ones that fragment. And he knew that, measured it, and wrote about it extensively.

 

[HandgunHTR]

Make your assumptions on what I say, if you can’t understand it doesn’t mean it isn’t understandable lol.

I am not assuming anything. Your words prove you really don't know what you are talking about. Using your own words, you are barely crawling with your understanding of physics, and as such what you are saying is not understandable to those of us who are running.

When a toddler babbles, I am sure it completely understands what it is trying to say, however for people who actually know the language, it is meaningless.

Do some research on the physics of energy transfer, work, torque, etc. and then come back to the discussion. If you can't understand it, that is completely understandable. It isn't for everyone.

The biggest problem that I see is that the firearms industry (just like the car industry) has tried to dumb down the physics for so long so your "average person" can "understand" that they have actually created a whole population of people who think that they actually do understand physics. Let me clue you in. You don't. Your continued misuse of terms, failure to grasp certain physical laws, and incessant belief that we can accurately creat a mathematical model of something when there are multiple very important variables that are significantly different from sample to sample just proves that.

 

[Vern400]

Sufficient energy velocity is needed to ensure proper projectile expansion. Beyond that energy is irrelevant. The resulting tissue damage from proper projectile placement is key.

Plenty of elk have been killed with a 6mm projectile having “only” 80 ft-lbs of KE. Right through the heart or lungs and they die. Every single time.

Velocity and energy are directly related for any bullet of given weight
A 22 long rifle has about 90 ft lb at the muzzle.
You sure about all that?

 

[Maverick1]

Sufficient energy velocity is needed to ensure proper projectile expansion. Beyond that energy is irrelevant. The resulting tissue damage from proper projectile placement is key.

Plenty of elk have been killed with a 6mm projectile having “only” 80 ft-lbs of KE. Right through the heart or lungs and they die. Every single time.

Velocity and energy are directly related for any bullet of given weight
A 22 long rifle has about 90 ft lb at the muzzle.
You sure about all that?

Sure about all of what? I am not certain what the question is.

The formula for KE is:


Anyhow, yes, I am 100% confident that plenty of elk have been killed with a 6mm projectile having "only" 80 ft-lbs of KE. That is the setup of my bow. A broadhead sent right through the heart or lungs and they die. Every single time.

I stopped looking at this thread about 15 pages ago, it just keeps popping up on the "New Posts". Have not gotten an answer if there is a way to "ignore" a specific thread on the forum.