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There is one thing I’ve learned thru all this .....

There are NOT 3 correct answers to 1 question.

Ain’t no thang to me. I shoot rifles with MORE than ‘enuff’

I won’t be UNDER gunned ! .

Jerry

I'm glad all the animals I've shot aren't into physics, especially the ones I've used a big and relatively slow bullet on.

To be fair, in all that shooting, I have noticed that deer seem to be more susceptible to fast and somewhat frangible bullets. I tend to go slightly towards the heavy side with a bullet to avoid excessive damage, though.

You and he are entirely correct about it not being a good indication of stopping power, but it is available and advertised, so it winds up being used for comparisons. As saddlesore mentioned, Colorado specifies downrange energy as a criterion for legal taking methods. Actually, I often use 450,400, because I tend to remember the product of g and 7000 as 225,200, apply the 2 and get your number. Whatever works....

All of that and I’ve seen 243’s drop game harder than a 7mm mag

Really ?
That’s different from my experience. ? Maybe the 7s bullets were too tough ?
Don’t know, am not arguing.

Jerry

Will the same energy lift 1# 2000'?

theoretically.....yes

I don't know the veracity of the story, but an old hunting pard told me of the time he stumbled onto the "deer cave". You know, that haven where all the deer run and hide in upon hearing the first shots fired on opening day. He said he saw charts tacked on the wall showing the ballistics of all cartridges known to to be favored by hunters, including foot pounds of energy and clinical descriptions of wounds inflicted by all the offerings of the bullet manufacturers at the time. Evidently the wise old bucks held classes for the youngsters, to while away the days until it was safe to go back outside again. One thing that struck him, he said while lifting the sixth shot of Wild Turkey to his lips, was the big warning in red hanging over all those charts, graphs and 8x10 glossy color photographs, that cautioned the herd to be extra vigilant about hunters from the 24HCF sneaking around the woods.

I was matching the duffer shot-for-shot, so I didn't much care if he were bullshitting me or not...

Now, THAT’s a good one. 😂😂. Being able to laugh at ourselves is healthy.😄

A Toast to gnoahh !

Jerry

I've heard rumors about that for quite awhile, thanks for the confirmation. Rumored that pigs were doing the same, but since their vision is not so good they were using braille read with their nose.

It did if, the shooter was using one of Bullets that “comes from untogether” upon impact, that so many people seem to favor these days! memtb

Steve,
This is in reply to your post, but ran on and is not aimed
to insult you.

I think these things go on because one side worships FPE,
and the other discounts it.

They are both wrong.

It's like talking horsepower and torque,
measured on a dyno, but used in the real world.
Rpm range, gearing....all factor in, and can skew results.


That 22-250 will be way more effective on varmits, coyotes, probably
even deer. Definitely if you use proper bullets for game.

Effective, as in fewer seconds to death.

Very possibly even in elk or moose if it's a lung shot.

That said, it's not a big game cartridge, and my scenario requires
too many things to be right.

Your big cast bullet will not destroy in the way a fast cartridge can,
it will do it differently. Deep long wound channels, breaking or penetrating
bone, mud whatever. Put that in the shoulder joints, hunts over.
No matter if it's antelope or bison.

For those who totally discount FPE, tell us
what we can use to measure the killing effects of missiles.

Longbow with 2 blade broadheads to 505 Gibbs with the 22-250 in between.
Give us a metric that precisely defines every stop.

Any that I'm aware of are useful, but only in Apple's to apples
comparisons. And even then, are skewed buy bullet choices, and other
factors.

Something often overlooked here is that others experiences might just
be as valid as anothers. But very due to many variables.
Big differences in hunting styles can mean big differences in guns chosen,
bullet placement/or choices of and obviously outcomes.

This is how I use foot pounds so energy- one pound lifted one foot.
If I climb a 3000 foot ridge with 4 extra pounds of fat or gear I have expended 12,000 foot pounds of needless wasted energy that day. On a 7 day hunt it is 7x that.
This expenditure is onerous in my books. Yeah , I watch my figure and carry lightweight gear . Hunting can be an endurance event.

Interesting analogy, but it’s even more complicated than that. It’s more like the energy generated inside the cylinders of the engine as related to the outcome of the quarter mile race. The results depend on so many other factors, that the energy generated inside the engine is a terrible metric to use to predict the results. The aerodynamic form of the vehicle, mass of the vehicle, the traction between the tires and the tarmac, the gearing ratio, mechanical loss, energy loss to noise and heat, etc, all play a role in how much acceleration the vehicle experiences.

Similarly, kinetic energy of the projectile at the muzzle is a terrible metric for predicting the terminal results on an animal. Some of that energy is lost to air drag, some is converted to noise and heat, some is used to displace vital tissue, some is used to deform the projectile, some is converted into vibrations in the tissue, some is used to displace fat, hair, hide, and non-vital tissue, etc. The only relatively well-correlated metric is not the kinetic energy of the projectile, but how much vital tissue is destroyed, and that largely depends on a bullet arriving with enough velocity to expand the projectile, and for it to penetrate through the vital organs.

What we need is a good 270 vs 30-06, wounding ballistics, and pressure thread....

There is no rigorous way of predicting the effects of a bullet wound. However, some basic physics can get us into the right ballpark.

Kinetic energy, momentum, and force are all intimately related. If you assume constant bullet mass, and know how velocity unfolds over time, you know all three things.

In a bullet impact, kinetic energy is not conserved. It goes to crushing and tearing tissue (permanent wound cavity) and into elastically stretching it. Cranz's Law is that wound channel volume is proportional to bullet kinetic energy, but that only sort of works, and only on slow projectiles. Kinetic energy (foot pounds) is really not a good predictor of bullet effectiveness. A single neutron at warp 9 and a 325 grain 45 caliber bullet might have the same KE, but produce very different results.

Momentum is a bit better predictor. Momentum is conserved when a bullet impacts.

On impact, the bullet sheds momentum, and the force it exerts on the tissue ahead of it is the rate at which the bullet is losing momentum. When the bullet loses enough momentum, it can no longer exert enough force to crush or tear tissue, and it comes to rest.

I think it boils down to good placement, a good bullet, and enough speed and diameter to produce a 1/2" hole 16" long.

NO!! A pox on you!

Well said, denton. Don't forget the 9 mm vs. 45 ACP debate!

Because kinetic energy is not conserved when the bullet hits the animal, and it is not a perfectly elastic collision.

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