Questions about the irrelevance of energy (ft-lbs)

[Formidilosus]

Correction it was Mass, velocity and bullet construction. Without the first two bullet construction would have meant nothing.

Does ft-lbs of energy tell you how deep a bullet will penetrate?


A direct “yes” or “no”.

 

[RancherJohn]

Best performing how exactly?

Better penetration, especially through a barrier like plywood (shoulder) with a max cavity that is deeper into the block and a cavity that extends further into the block. All with less "energy".

 

[FredH]

Does ft-lbs of energy tell you how deep a bullet will penetrate?


A direct “yes” or “no”.

Kind of funny there. Yes or no? Depends on the bullet doesn't it. Yes or no? It can.

 

[Formidilosus]

Kind of funny there. Yes or no? Depends on the bullet doesn't it. Yes or no? It can.

Ok- 3,000ft-lbs of energy penetrates how deep?

3,000 ft-lbs of energy penetrates how much deeper than 2,000 ft-lbs of energy?


This is a good faith discussion I am trying to have with you.

 

[FredH]

Better penetration, especially through a barrier like plywood (shoulder) with a max cavity that is deeper into the block and a cavity that extends further into the block. All with less "energy".

More narrow wound channel. Is penetration through plywood your only criteria? Bullet construction decides how energy is used. Lower velocity will allow deeper penetration because it causes the bullet to expand less/maintain weight within reason.

 

[SteveAndTheCrigBoys]

More narrow wound channel. Is penetration through plywood your only criteria? Bullet construction decides how energy is used. Lower velocity will allow deeper penetration because it causes the bullet to expand less/maintain weight within reason.

So you're using velocity and bullet construction to predict aspects of terminal performance...

It's almost like that's what everyone's been saying this entire time...

 

[bmart2622]

Let’s count the ways that this doesn’t matter one little bit. And lmao of at ‘objectively’...that’s friggin hilarious.

Comparing two shades fo death of known performers. And animal dies both times. While one guy says the one that went further was the better choice. Didn’t replicate it with the other but talks about it as if it isn’t as good of option when in reality the 168 may have flattened the deer and the 108 may have been a 30 yard runner. Like what the actual fack. Who give a fack?

We need to stop doing this, someone sure got a hard on for his little pet bullet. I got all kinds of pics like that too from slow ass Grendel and 123 eldm and hard quartering 2nd last rib and under hide in front of brisket at 200 yards etc and go on and on, a 420 yard quartering whitetail at 1700 fps impact and in the front and out the rib cage after 15” of swimming. Slow it down and it holds more sd then does what? Penetrates, oblongs the energy transfer. Speed it up and compresses the work curve more.

But it’s all blah blah blah words. Until we curve our bullets and all useful velocity ranges that is all we can do is run our silky mouths.

What good does that pic do? Not a single facking thing do we solve by looking at another result of death and blab about it.

And what the fack are you talking about the 168 doesn’t penetrate? I shot my big ole cow moose at 275 three times this fall broadside launching 2592 fps. Didn’t recover one. Through the lungs two steps, then through the shoulders knocked her down, then through the spine when she tried to get up one last time. Happened quick. Moderate velocities are magic with eldm’s at .25 sd. My 200 yard antelope sure didn’t slow it down nor a 175 yard whitetail that went 15 yards. While the same season my whitetail went 15 yards with the 168 we had 5 Grendel kills to 250 on deer and antelope that all drt’d so the 308 might be better match for the bigger bodies lol.

But without doing what I say needs doing we waste our time telling the story if attempting to argue about it’s effectiveness compared to another option. We need data if we’re gonna do that. Work data not result of work data. We pulled the trailer, yay, what engine pulled the trailer and what was its work curve? How fast did it pull the trailer?

Then quit talking and do it!!! Show us the numbers!!!!

 

[hereinaz]

This thread is the equivalent of a marginal shot with a high energy mono - for the last week and a half I've been waiting for it to die.

It’s more like the shot and the animal gets left overnight, and weeks later it’s still living…

If you don’t read the beginning it’s dumb to waste time arguing. It’s been covered.

 

[Lou270]

Here I think is what people do not get. Energy does not “do” anything. It is like charge on a battery that is spent doing work as bullet penetrates. Penetration is determined by sectional density (of final shape of projectile not starting) and velocity^2. This is very well tested and understood. There are various papers with formulas for Penetration in ballistic gel (particularly for non expanding projectiles) that correlate very well since it is unform media. Smaller diameter bullet will transfer less energy as it penetrates than a larger diameter projectile since it has a smaller surface area (ie resistance) Saying another way you can get similar penetrstion in a smaller cal as larger cal with less energy at impact (again, similar sd/velocity). It will just do less damage since less energy is transfered doing work as the bullet penetrates (ie smaller area). You can increase wounding with the smalller diameter projectile bullet by fragmentation to compensate for smaller surface area which will result in less penetration since you are effecively decreasing sectional density and gasp! Increasing energy transfer (ie lowering bullet mass) in a shorter distance

Bone complicates things some since it is a “hard” substance and requires a certain amount of pressure/energy to fracture . And no, I am not going to quantify that as I don’t know and it depends on type and thickness of bone. I am just pointing out that KE has some relevance for penetrating hard materials or more importantly what is left after a bullet penetrates to comtinue penetrating/damging tissue

Lou

 

[Stinky Coyote]

Does ft-lbs of energy tell you how deep a bullet will penetrate?


A direct “yes” or “no”.

No

You need sd and impact velocity to start to complete the equation of penetration. (Key word start) But it is part of of the equation, collective blinders on or not.

 

[hereinaz]

gel picture

fbi example - what is given for info, impact velocity, 16" travel, finished diameter and weight, bunch of work along that travel represented visually by damage of various types

what I want to know is...

at the 7" mark what was the velocity, bullet weight, and sd...so from there we could see the work being transferred, and again what was it at the 8" mark, 9" mark???? and every damn inch of that travel, ie; what is the rate of bullet change in relation to the rate of work transferred, and more, where is the bulk of the workload along the travel, how much is that workload

what's the work transfer curve of that option? the dyno? what work output is it doing at this particular swim speed? or that swim speed? is it all at the front end where most useful? or do I need a linear option because the game is much larger than normal and need to get deeper as a 1st priority?

and I wanna see it at all useful impact velocities whether by doing every 200 fps and filling in the blanks from the deltas between and v-lookup tables feeding the outputs from the background etc....whatever it takes

we can't see any of that yet, but the info is there, we just need to learn how to get it

I hear those Garmin zero's are the sh1t...can they measure through gel? haha

we have only begun starting to ask the right questions on this

Just begun to ask the questions? IMO, all you’ve done is ask whacked out questions.

With math you can calculate the velocity transition and deceleration from entry to the time a bullet or its parts decelerate.

Seriously, why don’t you answer one of your own questions?

 

[Stinky Coyote]

Then quit talking and do it!!! Show us the numbers!!!!

My goodness, better start on page 1 and it’s also been covered. That’s what we haven’t learned to do yet and need to do. Don’t be the one legged man here, read the whole thread. Process it and then come back when you think you’re on both legs.

 

[Stinky Coyote]

Just begun to ask the questions? IMO, all you’ve done is ask whacked out questions.

With math you can calculate the velocity transition and deceleration from entry to the time a bullet or its parts decelerate.

Seriously, why don’t you answer one of your own questions?

Do you have the tools to measure the velocity, mass, amd sd at the 2” mark, 7” mark, 10” mark? Let me know when you find them sand it will be easy to math the work at each point. And that would be for one impact velocity only.

The post you quoted I did a full length breakdown of work transfer per inch but linear. We all see that the work isn’t linear on rapid expansion family so we’re gonna need some new tools to measure swim velocity and mass and sd along that full travel and show it in a curve like a dyno chart for any engine. And at all useful impact velocity ranges we need to see it.

Until then you can use my math to better predict a bullet performance from single impact velocity gel pics you find online crudely by just work per inch. At least for that impact velocity given in the pic. Use your imagination for realistic hunting impact velocities lol. Like all we ever have done and will continue to do.

 

[Stinky Coyote]

Ok- 3,000ft-lbs of energy penetrates how deep?

3,000 ft-lbs of energy penetrates how much deeper than 2,000 ft-lbs of energy?


This is a good faith discussion I am trying to have with you.

I’ll also take a run at it.

Same bullet? If a solid with no change in sd then 3000 ft/lb would penetrate the percentage difference between it and the 2000 ft/lb further minus the faster it goes the faster it slows quadratic whatever. There may be an efficiency point where things are similar for certain static sd ranges but the 3000 ft/lb will add some damage over the 2000. How much so we have no idea and a picture of a deer’s ass only fuels the discussions further.

Variable sd bullets the slower 2000 ft/lb one likely go deeper or as deep as depending on how fast the impact is will drop the sd much quicker and shorten the penetration of the 3000 ft/lb but the excess energy moves outward when that happens. How would we know though without dyno-ing it?

There’s a reason why I like .25 sd eldm at moderate velocities as it’s been consistent from up close to as far as 1700 fps comes. Seem to go similar depths regardless but closer in I do see maybe a couple inches less with more violent damage but overall has been balanced and drt and 2500-1700 is a good range for it. I know with more speed the up close stuff I’d likely want to add some sd to make sure it didn’t go too shallow. I’m a zero to 600 guy though so my window isn’t chosen by accident.

How much of any of that we don’t know because we don’t measure it. So we have this back and forth endlessly.

It’s funny how people get hung up on energy as more or less is better, or irrelevant. That isn’t what I’m saying or arguing. I’m arguing it’s relevant if we learn how to measure it as it is applied over the travel. And when we do and get enough data we will see by numbers, objectively why it delivers the results we see and compare to others. And choose from better info going forward.

Gonna need to grab a couple more gears, expand your thinking, if we’re gonna break free of this misery cycle we’ve been trapped in all this time.

 

[Stinky Coyote]

Ah yes, there it is!! When you cant back up or substantiate any of your ridiculous claims, you resort to personal insults....classic keyboard warrior tactic!!!

I accidentally did a double post. An echo. Anyone who’s seen the original predator movie will understand the big puzzy remark, classic joke, it wasn’t an insult to you, if anything to me for double posting and not sure how I did it lol.

 

[Bugger]

Theres zero chance any equation you come up with will have any relevance to a real world wound channel. Both the projectile velocity and impact material are wildly inconsistent. A shot slipping the ribs into a fully inhaled set of lungs will have entirely different resistance than a shot to a 3” thick front qtr knuckle and dense organs on the same animal.
No matter what wazoo cabin fever equation you come up with, there is no substitute for proven wound channels.
Unless you can come up with an answer as to WHY it matters to calculate work/distance, then you’re just being a troll not the ideas guy.

 

[RancherJohn]

More narrow wound channel. Is penetration through plywood your only criteria? Bullet construction decides how energy is used. Lower velocity will allow deeper penetration because it causes the bullet to expand less/maintain weight within reason.

Just bringing the conversation back around to 'energy is needed for penetration through shoulders/angled shots", which you brought up earlier.

Also, there is a 71 fps impact velocity difference, less than the SD of some boxes of ammo. We aren't talking 1800 fps vs 2800 fps, we are talking 2647 fps vs 2718 fps.

I'm also glad you came around to realizing that velocity is the driver of expansion, bullet construction determines how it expands and comes apart.

 

[bmart2622]

My goodness, better start on page 1 and it’s also been covered. That’s what we haven’t learned to do yet and need to do. Don’t be the one legged man here, read the whole thread. Process it and then come back when you think you’re on both legs.

Still waiting on some numbers

 

[Sundodger]

I don't know why, but I have a desire to stir the pot today.

Love you guys!

 

[Stinky Coyote]

Theres zero chance any equation you come up with will have any relevance to a real world wound channel. Both the projectile velocity and impact material are wildly inconsistent. A shot slipping the ribs into a fully inhaled set of lungs will have entirely different resistance than a shot to a 3” thick front qtr knuckle and dense organs on the same animal.
No matter what wazoo cabin fever equation you come up with, there is no substitute for proven wound channels.
Unless you can come up with an answer as to WHY it matters to calculate work/distance, then you’re just being a troll not the ideas guy.

Start at the start. Does not matter what the wound channel is in animals. What matters is showing/measuring the work in gel constant so we can look for what we want across all bullets for hunting and all impact velocities hunters use.

We use the work curve for vehicle engine to know what we want for that vehicle regarding work (total work and speed of work) and it’s a multitude of personal desires and needs that is different for everyone. Trailering potential, acceleration potential. We are not talking about the same thing here. You don’t compare all the engines available in a vehicle segment your interested in?

We can’t compare this in bullets yet. We have decades of posts, pictures, and every imaginable personal interpretation of the result of work, that does not further us in the ability to compare and choose from better information.

We need to progress to modelling that work. Not continuing to study the result of work.

It’s logical, whether or not it computes for everyone isn’t a me issue. I put in lots of try to help move this to a place we haven’t gone before because it’s obvious we have been spinning wheels on this for far too long and taking same path doesn’t get us out of the mud hole.