Questions about the irrelevance of energy (ft-lbs)

[FredH]

Love it, page 34 and we’ve added bra size/eq ratio for evaluating women as a yet another subjective to subjective comparison.

Certainly there’s no problem.

That just might be the most important revelation of this thread!

 

[TaperPin]

A deep chest makes the cup size look a notch larger and more high performance. This appears to be proof enough for me. No offense to the minimalists who insist on itty bitty ones going as slow as possible.

 

[doc holiday13]

Since energy is a calculation based on mass and velocity why is it not relevant? Obviously all you need is 556 foot pounds of energy and a 77 grain bullet that flies apart inside of 12 inches of penetration. Again obviously this is more effective than a 150 grain bullet going 1800 fps that creates a 3 inch wide wound channel for 10 inches and gets 26" of penetration with an expanded diameter of .580. That is what 1090 foot pounds of energy looks like with a controlled expanding bullet from a 30-30.

If we were to overlay your example on the graph i put in my Wallop thread this would make sense. KE is great but if there is not sufficient transfer of KE of the bullet into the target vitals, the chance of lethality goes down.

Also if your KE is transferred immediately your bullet will 'splash' on target and only maim the quarry. Hence why bullet construction is so important. Again if you look at the graph posted you'll notice that both ideal bullet and non ideal bullet are not making contact at 0 engergies. They have to hit with enough energies to penetrate, but if the energies expended over distance is not a steep parabolic like curve, the wound channel won't be big enough

Right now i'm currently debating which bullet is best because I'm not a fan of additional lead in my dinner. I've had great success with ELDM and ELDX in 7mm flavor. I've shot 1 deer with and ELDM and 1 with ELDX, both were full pass thru with golf ball exits. The ELDM was a 110 yard shot with a 45ish yard run The ELDX was a 204 yard shot but it was a BangFlop A friend of mine shoots a lot of Bergers, and shoots more animals than I do. He is all in on smaller calibers, but prefers a "bang flop" like anyone else. His opinion on Bergers has fallen. I've told him that he should move to ELDX or ELDM but he's probably just gonna move to a 6.5 caliber

 

[FredH]

If we were to overlay your example on the graph i put in my Wallop thread this would make sense. KE is great but if there is not sufficient transfer of KE of the bullet into the target vitals, the chance of lethality goes down.

Also if your KE is transferred immediately your bullet will 'splash' on target and only maim the quarry. Hence why bullet construction is so important. Again if you look at the graph posted you'll notice that both ideal bullet and non ideal bullet are not making contact at 0 engergies. They have to hit with enough energies to penetrate, but if the energies expended over distance is not a steep parabolic like curve, the wound channel won't be big enough

Right now i'm currently debating which bullet is best because I'm not a fan of additional lead in my dinner. I've had great success with ELDM and ELDX in 7mm flavor. I've shot 1 deer with and ELDM and 1 with ELDX, both were full pass thru with golf ball exits. The ELDM was a 110 yard shot with a 45ish yard run The ELDX was a 204 yard shot but it was a BangFlop A friend of mine shoots a lot of Bergers, and shoots more animals than I do. He is all in on smaller calibers, but prefers a "bang flop" like anyone else. His opinion on Bergers has fallen. I've told him that he should move to ELDX or ELDM but he's probably just gonna move to a 6.5 caliber

My next experiment is going to be a 110 grain CX designed for the Blackout going 3150 fps from a 308. Gives me everything, large fragments moderately good penetration. A bang flop happens often with average cup and core bullets going average velocities. It happens pretty often with bullets starting out at more than 3000 fps. And it happens with fragmenting bullets at various speeds also. I don't really care if an animal runs 50 yards before it drops, it is nice when the heart is still pumping blood while doing so and remains edible.

 

[Bluefish]

Imho this is why energy is not a good indicator of performance (aka irrelevant), all three bullets do the same work on the animal, but starting energy is different. In the end it’s a function of the bullet, not energy.

 

[FredH]

Imho this is why energy is not a good indicator of performance (aka irrelevant), all three bullets do the same work on the animal, but starting energy is different. In the end it’s a function of the bullet, not energy.

Energy can only roughly calculate how big or small the "hole" is. With soft bullets you get big wide holes, with hard bullets you get narrower and longer holes. If both have the same energy then theoretically the volume of the "hole" will be the same. I tend to believe though that a larger bullet would have slightly larger volume than a smaller bullet with the same energy simply because the heavier bullet would either have more mass to fragment or more weight to penetrate.

 

[Macintosh]

Energy can only roughly calculate how big or small the "hole" is. With soft bullets you get big wide holes, with hard bullets you get narrower and longer holes. If both have the same energy then theoretically the volume of the "hole" will be the same. I tend to believe though that a larger bullet would have slightly larger volume than a smaller bullet with the same energy simply because the heavier bullet would either have more mass to fragment or more weight to penetrate.

Sort of, but to add to why energy doesnt correlate to wound size:
1) Passing thru=energy not doing work. Whatever energy is still carried by the bullet as it passes thru can no longer be transferred to making a hole in the critter. A passthru is the definition of transferring less than 100% of the possible energy into making the wound.
2) the RATE of energy transfer determines the peak force or f max placed on the tissue. Its the equivalent of being in a car at 60mph, and either slamming into a concrete bridge abutment (60 to 0 in .01 seconds, extremely high rate of energy transfer), versus gently applying the brakes over a couple hundred feet (60 to 0 in 20 seconds, slow energy transfer). Same amount of energy…which one do you feel on your seatbelt more? This rate of transfer has a lot to do with the size of both the temporary and permanent portions of the wound. This is not the impact velocity, this is differences in bullet upset in tissue causing it to lose velocity (ie transfer the energy) at different rates, measured in tiny fractions of a second…tiny differences matter a lot in this case because it exponentially affects the peak force applied to the tissue around the bullet. Peak force and total force are very different.
3) an additional wounding mechanism (bullet fragments cutting stretched tissue during the temporary stretch cavity) is not energy-based, the same way an arrow cutting thru tissue is not energy-based.

 

[Bluefish]

Energy can only roughly calculate how big or small the "hole" is. With soft bullets you get big wide holes, with hard bullets you get narrower and longer holes. If both have the same energy then theoretically the volume of the "hole" will be the same. I tend to believe though that a larger bullet would have slightly larger volume than a smaller bullet with the same energy simply because the heavier bullet would either have more mass to fragment or more weight to penetrate.

You are sort of proving my point. It’s the bullet that determines the hole size, not the kinetic energy available. Big soft bullets going fast do lots of damage, yet a big fmj going fast doesn’t and a small soft bullet going fast can do a lot of damage as well, not as much as a bigger one for sure.

 

[FredH]

You are sort of proving my point. It’s the bullet that determines the hole size, not the kinetic energy available. Big soft bullets going fast do lots of damage, yet a big fmj going fast doesn’t and a small soft bullet going fast can do a lot of damage as well, not as much as a bigger one for sure.

The bullet determines the hole's shape not size. The amount of energy available determines the size.

 

[FredH]

Sort of, but to add to why energy doesnt correlate to wound size:
1) Passing thru=energy not doing work. Whatever energy is still carried by the bullet as it passes thru can no longer be transferred to making a hole in the critter. A passthru is the definition of transferring less than 100% of the possible energy into making the wound.
2) the RATE of energy transfer determines the peak force or f max placed on the tissue. Its the equivalent of being in a car at 60mph, and either slamming into a concrete bridge abutment (60 to 0 in .01 seconds, extremely high rate of energy transfer), versus gently applying the brakes over a couple hundred feet (60 to 0 in 20 seconds, slow energy transfer). Same amount of energy…which one do you feel on your seatbelt more? This rate of transfer has a lot to do with the size of both the temporary and permanent portions of the wound. This is not the impact velocity, this is differences in bullet upset in tissue causing it to lose velocity (ie transfer the energy) at different rates, measured in tiny fractions of a second…tiny differences matter a lot in this case because it exponentially affects the peak force applied to the tissue around the bullet. Peak force and total force are very different.
3) an additional wounding mechanism (bullet fragments cutting stretched tissue during the temporary stretch cavity) is not energy-based, the same way an arrow cutting thru tissue is not energy-based.

A bullet needs energy to pass through. If it has enough energy to pass through and make a 1 1/2" exit hole then as far as I am concerned I don't care how much energy wasn't imparted to the animal, there was enough.

 

[Macintosh]

A bullet needs energy to pass through. If it has enough energy to pass through and make a 1 1/2" exit hole then as far as I am concerned I don't care how much energy wasn't imparted to the animal, there was enough.

Id agree it was enough, the question is whether the amount of energy tells us anything at all useful to achieving that. If total quantity of energy is important to know, let us know how much energy it takes to pass thru a deer.

Or is it dependent on other variables? If so that proves my point. A 55gr 223 fmj has “enough” energy to pass thru. Need a 1.5” exit, thats what ive seen from a 6.5cm shooting a bonded lead bullet. But I’ve seen several non pass thru’s from a 3006 shooting 165gr sst’s. Must not be enough energy?

 

[FredH]

Imho this is why energy is not a good indicator of performance (aka irrelevant), all three bullets do the same work on the animal, but starting energy is different. In the end it’s a function of the bullet, not energy.

There is something missing in your comment. Logic. Without energy there is no function by the bullet.

Id agree it was enough, the question is whether the amount of energy tells us anything at all useful to achieving that. If total quantity of energy is important to know, let us know how much energy it takes to pass thru a deer.

Or is it dependent on other variables? If so that proves my point. A 55gr 223 fmj has “enough” energy to pass thru. Need a 1.5” exit, thats what ive seen from a 6.5cm shooting a bonded lead bullet. But I’ve seen several non pass thru’s from a 3006 shooting 165gr sst’s. Must not be enough energy?

The bullet's construction decides how much it penetrates or doesn't. A bullet can use up it's calculated energy by expanding dramatically which limits penetration, or as in a good controlled expanding bullet blending expansion and penetration to get both destruction and exits. It is idiocy not to consider bullet construction in the application of calculated energy. A bullet is in itself inert. It does not add to calculated energy numbers because it deforms. It applies the energy it has in the way it is constructed to apply it.