Norbert, Gerard and others who would like to discuss the topic:

One notable difference between the GS Custom FN solid and Norbert's Superpenetrator design is that the circumferential edge of Norbert's FN protrudes beyond the ogive for a bit, while Gerard's GS FN does not.

In animal tissue, what difference in supercavitation and penetration, if any, will be occasioned by that difference, assuming that all other variables are constant (same bullet diameter, same bullet weight, same velocity, same meplat frontal area)?

SUPERPENETRATOR:







GS CUSTOM FN SOLID:

I didn´t compare these bullets in tests or on animals..
The main difference in construction is: The SP has a strong, not deformable design, while the GS FN copper nose may form under impact a sharp, evtl. protruding edge which acts similar as the SP.
This fearure you can implement in other designs like a cup point.
I think some manufacturers will develop FN bullets which may provide properties close to the SP.

Norbert,

Let me try my question again since I may have obscured my own meaning. In the SP design, why didn't you have the ogive meet the extreme edge of the steel penetrator disc metlpat, rather than allowing the steel disc to protrude a little beyond the edge of the ogive? I am wondering if that little bit of protrusion improves penetration, and if so what the fluid dynamics might be which would cause it. Thank you.

Is this the same technology that the Russians use on there submarine torpedos,the disc in the nose.
I saw it the web somewhere,having to do with the missile riding in the bubble created by the disc??


Sean

quote:

Originally posted by 500grains:
Norbert,

Let me try my question again since I may have obscured my own meaning. In the SP design, why didn't you have the ogive meet the extreme edge of the steel penetrator disc metlpat, rather than allowing the steel disc to protrude a little beyond the edge of the ogive? I am wondering if that little bit of protrusion improves penetration, and if so what the fluid dynamics might be which would cause it. Thank you.

500 grains,

It protrudes about 0.5 mm and it helps to generate the low water pressure for evaporation and keeps the beginning of the bubble off the ogive. The idea came from related phenomena, where protruding elements enhance cavitation. High velocity in the whirls = low pressure.
The first supercavitating torpedos from the russian "Kursk" also used a protruding disk. My first experiments with it on the range were so impressive, that spectators were fascinated. But soft copper FN can form a protruding edge also, may be by chance only.
Matching diameters also work, but in some cases the protruding edge was more reliable, so I stuck on this concept.

Sean:
Yes

Norbert,

Do you have pictures of any SP recovered from elephant heads?

Norbert,
Does not the flat nose pile up the stagnation pressure and induce kinetic energy transfer to the incompressible fluid (water), or water containing tissues, in the form of heat?

Does this not vaporize any water content of tissue to form a steam or vapor bubble being created and expanding and streaming off the nose at supersonic speed as the bullet passes?

Is this not a shock wave of sorts that helps to split the tissues and water at the leading edge of the bullet, and stream backwards over the shank in an envelope of steam or vapor?

Does this not help to stabilize the bullet due to less friction on the shank in this temporary cavity as elastic tissues bulge aside in the wake of the nose?

And a large flat meplat is efficient at this pressure and vapor envelope generation at the nose and streaming rearward.

And your steel SP disk with the 0.5mm overhang improves the maintenance of the flow dynamics and helps the bubble expand around the shank, reducing drag?

5000 ft.lbs. of kinetic energy raises the temperature of 1 pound of water 3 degrees F.

Almost all bullet energy ends up as heat dissipation if the bullet stops in the medium, like a solid bullet stopping in a swimming pool.

I can see that a micro-drop of water super-heated in a fraction of a millisecond at the nose of a bullet would facilitate a sudden expansion, in addition to the mechanical displacement of momentum transfer and elastic rebound.

I think it is obvious that the FN and SP are better penetrators in live game that is about 70% water.

It seems to me that they are Better-Penetrators and Super-Penetrators.

I will never use another round nosed solid if an FN/SP/FP solid is available.

Forgive any technical errors or ignorance, but that is the way I see it, for I sold my fluid mechanics text back to the university bookstore 30 years ago.

Are there any feeding snags with that sharp edged steel disk on the nose of the bullet as opposed to the rounded edge of the larger meplat on the GSC?

I know that the GSC's feed well in .375, .416, .475, and .510 calibers that I have tried.

What calibers and weights are the SP's being offered in.

To anybody who doesn't like the grandiose bullet name "Super-Penetrator," I say a rose by any other name would smell as sweet.

It is the name of the bullet, and it is at least a Better-Penetrator, or at least as "Super" as any game-penetrator gets, surely, in my-humble-wants-more-experience opinion.

.

Alf,
I sold my thermodynamics text too, but I think there will be changes in the enthalpy of the animal if 5000 ft.lbs. of kinetic energy is introduced into its system by a .458 bullet.

If you hit a living tissue with a supersonic projectile, there is going to be a release of some free water from the physical disruption and heating, even from horn, hooves and bone.

I am out of my league here but can see the possibilities of better solids with the likes of the SP, FN, and FP.

I would rather not develop another nervous tic over this. I just got over the uncontrollable profanity tic induced by the other thread. I am clearing out to listen and learn.

Does the term "deminishing returns" apply here, I think so unless your stacking elephants side by side and testing the penitration on them..I am pretty sure both will go through one anyway..

.

RIP:
Good ideas. It is difficult to split the origin of the vapor bubble whether caused by Bernoulli´s fluid dynamics and additional evaporation by heat tansfer.
>>I think it is obvious that the FN and SP are better penetrators in live game that is about 70% water.And: If you hit a living tissue with a supersonic projectile, there is going to be a release of some free water from the physical disruption and heating, even from horn, hooves and bone.<<
There may be other mechanismen how the water is released and builds the vapor bubble.

In any case the piled up (stagnation) pressure induces a hydrodynamic pressure wave, which results in severe tissue damage. The wound channel looks like a path of a modern soft.
Of course the bullet experiences less friction, but the stabilisation comes from the rotational stabilisation, which is not stopped by friction. Ballisticians few years ago postulated, that RN FMJ bullets must tumble and can not go straight line, because the friction in the 1000fold denser target would stop the rotation. Bullets from smooth bores will try to build up cavitation, but immediatly tumble, because there is no stabilisation.

quote
>>Are there any feeding snags with that sharp edged steel disk on the nose of the bullet as opposed to the rounded edge of the larger meplat on the GSC?<<
Yes. Especially with standard lenght Mausers and cartridges in a zig-zag magazin should be checked for feeding.

>>What calibers and weights are the SP's being offered in.<<
9.3; .375; .416; .458; .470; now in standard weights and many light weight, not recommended for DG, but useful for plains game. But not commercial available in the US.

>>To anybody who doesn't like the grandiose bullet name "Super-Penetrator," I say a rose by any other name would smell as sweet.<<
It came from the short form of "Supercavitating Penetrator", not to create a grandiose name.

I just achieved intellectual ecstacy! Ahhhh...

I gotta agree with Ray on this one- in the end, they will kill.

Alf:
you are performing unnessesary brain acrobatic.
Any real liquid, even pur water, is not ideal, that means not Newtonian.
But flow is existent as well are whirls, which are not allowed in ideal liquids.
For our rough modelling it is irrelevant, how the water in living tissue is bound and by what mechanism it is released.
Or how many other molecules are dissolved. The strongest bond occurs between water molecules itself. (Hydrogen-bridge bonding).
Depending on the binding and concentration there is a vapor pressure lowering, which may affect the cavitation, but not prevent it.
Queeze tissue, or put it on a warm plate, you can see how easily water is released.

What counts are the observed phenomena, which directly or indirectly can only accounted for cavitation.

BTW: Thomson, "Mahohboh", page 106: Ele skulls honeycombstructure is filled with a watery liquid!

But now it is enough discussion on this matter. Let´s shoot animals with modern bullets and practice for good shot placement.

quote:

Originally posted by 500grains:
Norbert,

Do you have pictures of any SP recovered from elephant heads?

500 Grains:
I have a very few SP recovered from ele necks after a frontal head shot, but my upload software is on strike.
The design I am using (high copper content brass alloy with integral disk and lead core) shows only a few scratches and is integer at all.
The soft copper SPs with steel disc sometimes are a little compressed and shorten by impact as all the soft copper FN are affected from the stress.

.

Alf,

Without resolving the issue of Fackler versus Norbert, how would you explain the field observation that FN solids penetrate substantially deeper in large animals than RN solids, from the same rifle, same load?

.

Alf,

I do not care what bullets do in wood because wood is not closely analagous to animal flesh. I read the LaGrange book. Interesting. If I need to shoot my office desk, the book will give me good guidance.

As for field tests, I am not sure what you are asking for in terms of validated data. The only data I can supply is that which I collected. It is not a large sample space and no scientific conclusions can be drawn. But nonetheless, FN solids beat RN solids by a solid margin.

quote:

Originally posted by ALF:

In the very Archives of this very AR there is a thread pertaining to the wounding effect of bullets and all and sundry were quoting from the words of Dr Fackler and Macpherson that there is no evidence that a shock wave propagation is the cause of trauma to living tissue and further that the trauma is the cause of the direct path of the bullet ! Do you guys remember it ! all the gurus of this communtity were in complete agreement.

Alf:

That´s your technique: you always pick up some statements, do not understand it in its right context, put it into wrong correlations, argues with irrelevant facts and ask for nonexisting problems. Often you neglect my measurments and experimental data.
In my website I cite Fackler and he is one of my references.
Shockwave has a very different meaning than pressure wave. There is no shockwave, but as some here came up with the "stagnation pressure", the pressure wave is the extension of the pressure in front of the bullet.

quote:>>What I would like to see is what it looks like when we shoot all monometal solids of varying profile into water and then to photograph them to see Who does what?<<

Nobody would pay for that, but again, reading my website you can see, that I shot many kinds of solids into my test equipment. Even RN show stabilisation by supercavitation.. The varying profiles showed different straight line penetration according to their ability of establishing stable cavitation.

quote:>>Norbert claims that projectile path in the water medium is straight, it is far from straight and only if ideal physical requirements of both projectile and medium are met is the path straight. I have numerous citations that show this and also show how difficult the problem is to deal with.<<

Nonsense. I measured the bullet path in water as a straight line up to 3 meters. And in ele heads also I observed always straight wound channels from impact to exit.
You may have citations, but it only can take place in very different systems which are not dealt with here. And veering in water or animals takes place, when the cavitation collapses.

.

Alf,

You have not answered my question.

Do you know of any explanation for why FN solids are showing greater depth of penetration in field tests on large animals than RN solids?

Norbert's supercavitation work provides an explanation.

Do you know of any alternative explanation?

500grins,
You and I agree on something!

Alf,
Marty Fackler is an M.D. whose hobby and second calling is wound ballistics. His buddy Duncan MacPherson is an ex NASA engineer who has the same hobby.

I have read Duncan's book and some of Fackler's stuff.

They only down play the mythical-mystical "shock power" idea. They really make no statements antagonistic to this localized shock wave or pressure pile-up phenomenon being part of the mechanical aspect of localized wound. Just no such thing as total body shock incapacitating the perp or critter.

MacPherson published data, graphs, and summary statements agreeing that the truncated cone flat nose was superior in penetration to all other bullet types, as long as we are discussing solid type bullets.

It is written. I believe Marty would agree with Duncan whole heartedly, and vice versa.

I believe MacPherson's limited work with handgun bullets and ordnance gelatin supports the FN/FP/SP superiority idea.

I believe it only gets better as we step up to rifle velocities with solid FN/FP/SP type bullets.

.

Alf,

Silence can only be construed as acquiscence.

Alf,
We are not disagreeing about anything.

The impala's head pops becasue the expanding high velocity frangible creates a temporary cavitation and forces that exceed the elastic limits of the head. It pops. The high velocity FN solid might do the same thing if it is big enough and fast enough, or the head is small enough and soft enough, though likely less dramatic.

Ditto the elephant brain supended within the skull in CSF and meninges. Turns to mush along some of the temporary cavity and all of the permanent cavity.

Grenade shrapnel may or may not have good penetration depending on SD [:?)} and velocity.

We are not disagreeing on anything.

Please don't shoot me with one of those darts.

But the sea depth is not great enough and varying enough to affect pressures and the trajectory inside an elephant's skull. No curve allowances or sight adjustments needed there

.

Alf,

You are getting stuck on not believing the data. Let's skip that part. Assume the data meets your standards and that it shows FN solids penetrating 10-20% deeper than RN solids.

Can you offer any theory other than Norberts which explains that performance?

I have read the shoulder stabilization theory, but I think it is B.S.


(The data does exist, by the way, but I would like to skip that part for now since it seems to be distracting the discussion.)

.

Alf,

Your post can be boiled down to 4 words: "I don't believe it."

That's fine.

But you have not offered any theory which can compete with Norbert's supercavitation explanation. In a scientific inquiry, we start with a hypothesis, test the hypothesis by gathering data, and then compare the data to the hypothesis to see if the hypothesis adequately explains the data. If not, we need to re-work the hypothesis.

In the case of FN solids, Norbert's supercavitation explains their performance.

By the way, were you asking to see my data?

.

500 Grains, Alf, Norbert, RIP, Gerard,

Thanks for getting this lively conversation going.

Now you all need to roll up your sleeves and prove your point.

Shoot FN vs RN into water, about 11-12 feet of it, or IWBA calibrated gelatin, and then lets talk.

This is not an easy thing to do, alot harder than hitting the Reply key.

As Ron and Dan know, I have tried to add some emperical results to this discussion but have not really been able to gather any useful data. The problem is stopping 6,000 ft lbs of energy in 24 x 16 x 18 inch (16 gallon or 68 liter) containers.

These suckers are unstable and fly up, down and sideways.

After 6 hours set up and $100 in containers I only have three recovered bullets and none of it means shit.

Two RN went 49-60 inches before exiting sideways, and one FN went 126 inches (hurray, supercavitation) except it flew up and out of one 24 inch tub of water, skimmed 2 inches underneath water on next 2 feet, and then re-entered water world and dove down and out next one.

There are so many OTHER factors governing penetration, like stability and the hardness and compression of the bullet, that it will be difficult to ever prove or disprove why a monometal FN may or may not penetrate better than a FMJ RN.

Since I know Marty Fackler, who nominated me to memberhsip in the IWBA, I would like to correct one misconception on this thread that he said, "Shock wave propagation" has no effect on trauma in human targets is totally misleading and incorrect. This was what he said about sub sonic and trans sonic JHP PISTOL BULLETS.

Marty is a vastly experienced battlefield surgeopn (Viet Nam) and knows very well what a 55 grain FMJ at 3250 fps looks like when it hits a human head, spleen, liver, or bowel. (About 7cm hole in bowel).

So watch who you quote and dont use it out of context!

As for the FN profile of the 30 x 173mm projectile, I am probably other than perhaps Alf, the only one on this thread who has ever shot a 30 x 173mm, and Ive shot hundreds of them, including what in 1994 was an experimental APDS-FS in a Hughes/McDonnel Douglas chain gun mounted on a Bradley A2 turret. (It just barely fit, the gunners face was right up against the breech).

I was shooting BMP-2 mock ups, 30mm high hardness steel inclinded at 80 degrees to simulate glacis of bow. At over 1,000 meters.

The FN design of the APDS-FS penetrator has nothing whats so ever to do with water. It was designed by Ballistics Research Lab at Aberdeen. Olin made it fly. The XM I shot had a pointed ballistic cap on the sabot like Alf shows in the mine clearance photo. The FN long rod penetrator underneath has that configuration not for super cavitation but because it puts the most possible KE over unit of Frontal Area onto the steel. The step up in caliber of the FN long rod is there so the penetrator does not skid off a 60-80 degree steel turret or glacis.

It has nothing to do with supercavitation guys!

It is there to penetrate steel, and all 105 and 120mm APDS-FS projectiles have a similar profile.

As a weapons effect guy I can tell you that there is not much left of that pretty little FN after a few milliseconds, especially with Depleted Uranium which is pyroiphic (burns in atmosphere). The tungsten penetrators last a few milliseconds longer, but the FN and step up are there so it takes a bite into the steel and puts the most KE over the smallest area.

You guys are all grasping at straws to prove a point.

Super cavitation is a religion, and you either Believe, or you are an Agnostic.

I got to see it to believe it.

When you test your RN and FN bullet designs, please remember to use a test medium that decelrates the bullet to the exact same penetration depth you acheive in a front on elephant skull shot.

Norbert has suggested to me this is around 60 inches.

Water is not nearly dense enough to be a realistic test medium. The La Grange stop box is actually alot closer. (My 450 Dakota w a 500 gr FMJ would do 72 boards or 52 inches of 3/4 inch thick plywood).

If anyone out there has shot a GS-FN or NF-FN through 12 feet of elephant starting at the skull, then water is a dandy test medium for FMJ's and monometals.

I respect each and every one of you.

And I am going elephant hunting in November!

Its all your fault.

Andy

Thanks, Andy,
Good luck on your elephant hunt.
I believe in the FN/SP/FP being a better solid. I take it on faith and by my anecdotal evidence.

The biting ability of the flat nose into slanted steel may also be a good straw to grasp at on elephant skulls too.

I'll take a flat point solid elephant hunting if I ever go, hope you do the same.

Enough of this quibbling. The flat point has proven best since John Buhmiller then Jack carter's TBSH, etc. Heck, Elmer Keith with his hard cast lead handgun bullets had something to do with it too.

I'll try the water containers some more, but wonder if a water tank with a square of 3/4" ply wood every 6 inches would be a better tester. Ordnance gelatin is not much better than water alone. Maybe a thick leather entrance/aiming point on the front of the tank to simulate the skin? Fun!

Cheers!

Here is some of my data (sorry Alf if it was not compiled in a laboratory).

On broadside shots on elephant, a GS Custom FN or Bridger FN .510 diameter will exit. A Barnes (same load, same weight, same rifle) will not.

Do you know why?

.

.

Alf,

If you look at the profile of any APDS-FS from 1980 onwards, starting with the 105mm M735, and progressing to the 120mm M827, you will see that it has a profile very much like the 30 x 173mm mine clearing munition you describe.

The only difference is a bit thicker mid section which probably does help in water, and the lack of a pointed aerodynamic windsheild on the penetrator.

It is 70 g heavier than a std 30 x 173mm APDS.

Basically all they did was take off the pointed aerodynamic spike and leave a fully exposed BRL penetrator.

Even the Spanish managed to imitate this in about '84 with their 105mm C-437 which looks alot likt the little 30mm APDS-FS.

It is nothing new, and what works on inclined steel glacis of a tank or IFV also works entering water (rather than ricocheting off).

The speed of sound in water is what?

The speed of sound in tissue?

Are elphant guns going this fast?

We all need to go hunting, or start mixing up Kind and Knox gelatin by the 55 gallon drum to prove this one way or another.

It wont happen here.

Good hunting!

Andy

.

Alf,

I was afraid of that.

So Ive got to get my elephant gun up to 4,700 fps?

Man, its whipping my ass at 2,500 fps now!

Maybe I will have to go elephant hunting with a three diameter FN cylindrical rod like the BRL penetrator?

It would be a goofy looking thing in a bolt action rifle, and would probably not feed worth a dam.

Imagine a wedding cake with three teirs. A SWC with a wadcutter on top of it.

Thats what we need!

It does work on steel, but then so does a .223 x 50 BMG.

Am not sure how far to apply military technology to elephant hunting. The Russian torpedo that first got Norberts attention is operating at several atmospheres of pressure, 300 m below the North Sea in freezing salt water. Not 100 degree F elephant hide. One reason it was so efficient is that the rocket motor acted as a gas generator and filled in the cavitation behind it like a Boat Tail bullet, or "Base Bleed" artillery shell that has a gas generator in its BT. This, along with a 45-52 caliber barrel length, is how we got the 155mm out to 40 Km.

Why do you not trust IWBA gelatin?

It has been regulated to both man and beast, and with bullets as different as 147 grain 9mm JHP and steel core 5.45 x 39mm FMJ's.

What monometal or FMJ do you use in your big bores???

Andy