Retained Velocity vs Retained Energy

[Rooggvc]

So I have been thinking a lot the past few days about ballistics and the killing power of bullets. I have always heard that hunters should shoot for a 1500 ft/lbs minimum for elk and a 1000 ft/lb minimum for deer. Well I got reading the .223 for Bear, Deer, Elk, and Moose thread. Many of the animals killed in that thread were killed far below the "1000 ft/lb" minimum. It seems in that instance they were killed because of the bullet construction and the velocity. So it has me wondering? Maybe bullet velocity, and determining a given bullets minimum velocity to reliably function, is really the main thing I should worry about?

What are your guys thoughts? Is velocity or energy more important?

 

[bbell]

Yeah that was a great thread. Disruption of tissue would be most important. So proper bullet at proper velocity.

I don’t look at energy numbers anymore. It’a just a math calculation using a couple things we know. Arrows kill pretty effectively and they have very low energy.

 

[MuleyFever]

This gets brought up and argued about so often.

 

[roadrunner]

Yeah that was a great thread. Disruption of tissue would be most important. So proper bullet at proper velocity.

I don’t look at energy numbers anymore. It’a just a math calculation using a couple things we know. Arrows kill pretty effectively and they have very low energy.

Except an arrow kills by slicing and mass hemorrhaging and drop in blood pressure whereas the builets kills as you say through tissue disruption via a hemorrhagic shockwave.

 

[Formidilosus]

Except an arrow kills by slicing and mass hemorrhaging and drop in blood pressure whereas the builets kills as you say through tissue disruption via a hemorrhagic shockwave.

What is a “hemorrhagic shockwave”? And how do projectiles kill by it?

 

[Rooggvc]

I am sure there are people on both sides of the argument. Just curious about real world experience.

 

[roadrunner]

What is a “hemorrhagic shockwave”? And how do projectiles kill by it?

Google it.

 

[MuleyFever]

I am sure there are people on both sides of the argument. Just curious about real world experience.

You just said you read a whole thread about real world experience.

 

[Formidilosus]

Google it.

I’ll answer: it’s not a wounding mechanism, and there is no “shockwave” that happens in tissue that destroys anything.

Bullets kill exactly the same as arrows- physiologically they damage tissue and kill primarily through hemorrhaging or suffocation. The same mechanisms that broad heads use. They just cause way more tissue damage than a broad head.

 

[MuleyFever]

Google it.

hemorrhagic shockwave - Google Search

www.google.com

?

 

[ODB]

What are your guys thoughts? Is velocity or energy more important?

Penetration is most important.

If you read enough books, especially ones about Africa, you will notice that cartridges that hit well above their weight almost invariably have one thing in common: the bullets they sling have an SD over .300 and usually closer to .330.

A few examples:

416 400gr .330 SD
375 300gr .305 SD
9.3 286 gr .305 SD
318 WR 250 gr .328 SD
458 500gr .341 SD
450 N.E. 480 Gr .327 SD
338 WM 250gr .313 SD
256 MS 160 gr .328 SD

The professional hunter Harry Selby told me the most penetration he had ever seen, from any rifle, was a 318 WR on a black rhino. It went in the chest and ended up at its tail.

 

[WCB]

Bullet construction at a proper velocity. Energy imo doesnt mean anything if the bullet cant stay together long enough to use that energy inside the animal. Doubt anybody in that .223 thread were using the TNT bullets on elk.

 

[roadrunner]

I’ll answer: it’s not a wounding mechanism, and there is no “shockwave” that happens in tissue that destroys anything.

Bullets kill exactly the same as arrows- physiologically they damage tissue and kill primarily through hemorrhaging or suffocation. The same mechanisms that broad heads use. They just cause way more tissue damage than a broad head.

I don't have the willpower to argue, but yeah, there is most definitely a shockwave that disrupts tissue causing the bleeding which casues all the other problems associated with significant blood loss.

A demonstration of a bullet passing through ballistics gel shows this.

 

[Megalodon]

I don't have the willpower to argue, but yeah, there is most definitely a shockwave that disrupts tissue causing the bleeding which casues all the other problems associated with significant blood loss.

A demonstration of a bullet passing through ballistics gel shows this.

This is just utter fudd logic bullshit. You can't argue the point because it's an untenable position. Welcome to the 21st century.

 

[Wapiti1]

Penetration is most important.

If you read enough books, especially ones about Africa, you will notice that cartridges that hit well above their weight almost invariably have one thing in common: the bullets they sling have an SD over .300 and usually closer to .330.

A few examples:

416 400gr .330 SD
375 300gr .305 SD
9.3 286 gr .305 SD
318 WR 250 gr .328 SD
458 500gr .341 SD
450 N.E. 480 Gr .327 SD
338 WM 250gr .313 SD
256 MS 160 gr .328 SD

The professional hunter Harry Selby told me the most penetration he had ever seen, from any rifle, was a 318 WR on a black rhino. It went in the chest and ended up at its tail.

ODB, That applies to solids. Softs are in a different realm. The sectional density is ever changing as the bullet upsets, or comes apart in the tissue. Then you have bullet construction, bonding, etc to contend with.

I'm not arguing the wisdom of penetration being critical for heavy game like a cape buffalo, just that sectional density is a poor predictor of penetration for softpoints.

Jeremy

 

[Mule3006Elk]

I don't think about it.

BUT if the minimum velocity is 1800 fps for good opening. I add 400 fps to that minimum. For this example my minimum velocity would be 2200 fps. I don't trust stated minimums and having the extra velocity gives me more confidence.

 

[ODB]

ODB, That applies to solids. Softs are in a different realm. The sectional density is ever changing as the bullet upsets, or comes apart in the tissue. Then you have bullet construction, bonding, etc to contend with.

I'm not arguing the wisdom of penetration being critical for heavy game like a cape buffalo, just that sectional density is a poor predictor of penetration for softpoints.

Jeremy

Disagree. The more SD, the more bullet you will have behind the expanding front end which keeps the bullet energy moving forward, pushing the expanded bullet through tissue. If a bullet retains 2/3 its length behind the mushroom it will penetrate deeper than one that only retains 1/4 of its length. Yes, a lot of things change when a bullet expands, but SD doesn’t disappear.

Penetration is still most important, even with soft nose bullets, however you achieve it.

 

[scattergun]

Bullet construction at a proper velocity. Energy imo doesnt mean anything if the bullet cant stay together long enough to use that energy inside the animal. Doubt anybody in that .223 thread were using the TNT bullets on elk.

Of course bullet construction is crucial, but velocity and energy are inseparable for a given bullet mass.

 

[Mule3006Elk]

Of course bullet construction is crucial, but proper velocity directly implies proper energy for a suitable bullet mass.

View attachment 450276

Can you explain the equation for those who may not understand. I had a year of physics so I get but not everyone will. Thanks

 

[Wapiti1]

Disagree. The more SD, the more bullet you will have behind the expanding front end which keeps the bullet energy moving forward, pushing the expanded bullet through tissue. If a bullet retains 2/3 its length behind the mushroom it will penetrate deeper than one that only retains 1/4 of its length. Yes, a lot of things change when a bullet expands, but SD doesn’t disappear.

Penetration is still most important, even with soft nose bullets, however you achieve it.

Only if the designs are identical, and not designed to shed weight at a high rate (Berger, TMK, ELD-M). A Barnes will always outdo a Nosler Partition of the same starting weight, caliber, velocity and SD.

Jeremy