http://sst.benchrest.com/ for tko calculation

.

And once again in this seemingly unending revisitation of penetration, I concede that a FN will probably on average deflect less than a RN and hence on average yield greaater penetration.

But what the hell, shoot 'em where you are suppose to and they go down.

Alf, I don't have time to even read your whole post at the moment because this is a busy day, but I think you are getting the concepts mixed up and reaching false conclusions. Cavitation creates a larger wound channel. Your assumptiont that cavitation means less drag means smaller wound channel simply does not bear out in the field. Keep in mind that as the cavitation (or supercavitation) bubble moves through flesh, the cavitation bubble itself has drag which I think your post ignores.

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quote:

Because of elastic rebound of the target medium in the case of muscle the permanent wound channel is actually slightly smaller than the caliber of the projectile if we assume the projectile passage is absolutely stable, non deforming etc.

In the case of a cylinder or a projectile with a sharp cutting edge the permanent cavity is a cleanly cut channel equal to the outside diameter of the projectile.

????????
Look at the following images. Two wound channels in flesh, the producing bullet (SuperPenetrator) is shown inside the hole. Next the entry of the bullet and another part of a woundchannel produced by the nondeforming special FN bullet with a sharp edged disk of 7.4 mm diameter!

quote:

Originally posted by Ganyana:
Just back from an ele hunt...

1st shot. .458 Lott, Hornady 500grn (one of the new brass cloured bullets). Perfect frontal brain shot that crumpled the ele in a flsh- but the bullet exited rear left of skull and hit a young bull in the trunk. Bullet must have turned slightly because the ele was in full charge and the shot was perfectly straight on.

That happened to me with this solids in 460 Weath.

Tumbling and deflection. The encapsulated bullet lost its lead completely.

.

quote:

Originally posted by ALF:

Cavitation does not create a larger channel if it did then the drag would be more !

I have to insist that it does create a larger wound channel as I have observed it in the field with FN solids and RN solids being shot side by side, same velocity, into the same animal at the same distance and there was a significantly larger wound channel with the FNs. And the phenomena is easily repeatable.

So what should I do, believe what I have seen in the field with my own eyes or believe what I read on the internet?

.

Alf,
believe me, the wound channel is through many animals tested as bigger than the bullet´s diameter.

quote:

There is off course another pathway: that is the theory of shoulder stabilization.

By self stabilization a flat meplat projectile keeps to a regimen of zero (or close to zero ) angle of attack progression, this reduces drag and ultimately deeper penetration.

You always don´t understand, what we are saying.
There is no first hand deeper penetration caused by reduced drag or other mechanism. There is minimal drag sideways in the bubble. It is the loss of stabilisation and the RN tumbles and evtl. veers off course ealier. In low vapor pressure fluids the penetration would be the same or even less.
If not water vapour, what builds up the cavitation bubble in your idea? Vacuum, evaporated proteins?
Re shoulder stabilisation. In my articles I gave some experiments and thoughts, that in case of hunting bullets it is not possible. And there is in literature no proof given. We discussed it in previous threads, but you did never come with any experimental proof.

.

Gentlemen:
Think about this: We know a Spitzer Solid will yaw and over turn, because the base weighs more than the point.

Thus it would seem that the more the "point" of the bullet, weighs the same as the base the less the tendency there would be for the bullet to yaw and overturn.

Take a close look at the German TUG bullet. The rear penetration portion looks the same on the front as the back for that reason.

The old Nitro Express Solid bullets were more pointed than todays Woodleighs.
This was especially true of the early 470's, which Taylor commented on that they did not penetrate as well as other NE rounds.

Modern tests have shown that the hemispherical RN Solids to not penetrate as well as the Woodleigh profile. Also the FN solids seem to penetrate better than the Woodleigh's.
I have shot 3 elephants with 480 Woodleigh solids and one with a 450 North Fork 450 Flat Nose Solid from my 450 No2.
I must say baised on this small sample the FN does penetrate deeper in elephant slull on brain shots than the RN.

I will also say baised on ALL the game shooting I have done over the years that a Flat Nosed bullet ,including a Keith SWC will always cause more damage than a RN, assuming both are solid type nondeforming.

After all, the reason we shoot expanding bullets is because we know a bigger more damaging wound channel results from a blunt [expanded] bullet.

The more damage, ie the bigger the hole the better.

You "genusisess" , can debate the "why and where foures"

It is nice to know why something works....
However when the ELEPHANT is 6 yards or less from you, and comming your way, it is good to know WHAT will work.

I though shoulder stabilization was a theory that had been de-bunked as being inconsistent with basic principles of physics?

.

While Prandtl is considered by many as the "father of modern aerodynamics" and played a good piano..... How many elephants did He shoot?

I thought the topic being discussed was "Penetration on Elephant."

Sometimes Alf stumbles over his intellect.

To bring us back to elephant hunting, here is an interesting story told to me by my PH Myles McCallum. He observed that Woodleighs often have a small bit of lead extruded out of the base of the bullet, as many have here observed, but only once seen them separate completely from its core.

An elephant bull was chasing his traker. He shot the elephant at near muzzle contact range. The 410 grain 416 bullet lost its core but killed the elephant. Good shooting on the run by Myles!

Do any of you gentlemen know Geoff well enough to suggest he bond his FMJ solids lead core?

I think it would make a good and reliable FMJ almost perfect. No one really knows if the lead deformation in FMJ's occurs because the bullet pitches or yaws or if the lead extrusion causes the bullet to pitch and yaw and then deform, but in either case bonding would almost surely help increase the rigidity of the good Woodleigh FMJ's.

Myles also observed that monometals almost always bent or deformed. He was not too keen on them.

Ted Gorsline commented on page 2 of this thread that the Trophy Bonded Sledgehammers have a tendancy to bend and I wold agree. I think this is because the ogive is so much lighter than the base of the bullet which is a bonded lead core. (SG of copper about 7 vs 11 for lead). A military spizer FMJ with a lighter ogive like the M855/SS109 which has a 10 grain steel penetrator ahead of a lead core upsets even at very high rotational velocity. JAck Carter probably thought as I would have, that having the hard copper or brass up front would prevent deformation but in hind sioght it appears this changes the CG enough to encourage the bullet to pitch or yaw and then it bends.

Interesting.

I respect all of you guys, including Alf, but can we keep the discussion to elephant hunting?

Andy

Can anyone provide evidence of a Woodleigh steel-jacketed FMJ not performing and killing effectively where mediocre bullet performance was the sole cause?

I have never heard or seen the shorter WDL FMJ bullet (relative to longer monolithic bullets) that had been strengthened with a thick steel jacket to bend. Some lead protrution at the back might occur on serious bone, but did it cause not to do its work as intended ... any examples?

Perhaps Ganyana can tell us more, as he is a fond user of the Wdl FMJ bullet.

Chris

Alf, Norbert & 500grains:

Aren't we missing something here that really causes the permanent wound cavity to be bigger than the bore or calibre size?

Similar to what Norbert and 500grains saw with their own eyes I saw when I shot a Kudu bull - my two fingers could easily be pushed into the wound channel made by a .308 GSC HV.
That was in the neck after the skin was removed.

Interesting, the exit wound through the skin was only calibre size!

I think what we are missing is all the 'auxiliary projectiles' created by the straight line, fast penetrating bullet being pushed viciously aside, in the case of my Kudu the totally crushed cervical vertebrae, enlarging the wound channel.
Note: these crushed bones did not exit through the skin, hence the calibre size only exit hole through the skin.

Don't you think this is a possibility?

quote:

Originally posted by truvelloshooter:
Can anyone provide evidence of a Woodleigh steel-jacketed FMJ not performing and killing effectively where mediocre bullet performance was the sole cause?

Yes, I know of one instance. A woodleigh 750 grain .585 diameter solid riveted and fishtailed off course upon hitting an elephant spine and only penetrated 1.5 feet.

quote:

Originally posted by ALF:


Let us just stand back and look at the basic premise of wound ballistics theory.

Projectiles that are shot through targets do two things, they crush /cut a path leaving what is called a permanent wound channel.

This is true, but very incomplete. Cavitation also leaves a permanent wound channel. And as others have pointed out, secondary projectiles also leave a permanent wound channel. To say that the only permanent wound channel is that actually cut by the bullet will be disproved with the first dead deer that is cut open.

quote:

In the case of a cilinder or a projectile with a sharp cutting edge the permanent cavity is a cleanly cut channel equal to the outside diameter of the projectile.

At the bullet entrance in the hide, usually. Along the wound channel and at the exit, usually the permanent wound channel is larger.

quote:

So if the channel appears bigger it can only be due to cutting effect by sharp edges and cavitation is not the factor causing the decrease in drag and better penetration....

This conclusion does not hold water because it does not explain permanent damage, such as tears in lung tissue, 6 inches laterally away from the path of an FN solid.

quote:

Originally posted by ALF:

Cavitation does not create a larger channel if it did then the drag would be more ! The cavitation bubble is only acouple of microns thick, it is definetely not the way the popular pictures depict it to be.

Is there some evidence of this?

And if true, then what creates the larger wound channels found with the use of FN solids?

quote:

Originally posted by Jagter:
Alf, Norbert & 500grains:

Aren't we missing something here that really causes the permanent wound cavity to be bigger than the bore or calibre size?

Similar to what Norbert and 500grains saw with their own eyes I saw when I shot a Kudu bull - my two fingers could easily be pushed into the wound channel made by a .308 GSC HV.
That was in the neck after the skin was removed.

Interesting, the exit wound through the skin was only calibre size!

I think what we are missing is all the 'auxiliary projectiles' created by the straight line, fast penetrating bullet being pushed viciously aside, in the case of my Kudu the totally crushed cervical vertebrae, enlarging the wound channel.
Note: these crushed bones did not exit through the skin, hence the calibre size only exit hole through the skin.

Don't you think this is a possibility?

Yes, it definitely does occur. But the entire size and shape of a wound channel beyond the diameter of the bullet cannot be explained solely by secondary projectiles. When someone shoots an impala broadside in the chest with a .300 mag. pushing a 150 grain bullet at 3100 fps, the distal side of the wound channel will be 2-3 fists wide, even if no rib is hit at entrance. It looks to me like there was a supersonic water splash within the animal's chest, conical in shape.

/

Does that mean I have been hunting elephant with a squirt gun?

quote:

it cannot happen unless our solid falls within that small group of solids that become fluids if they are stressed enough and then we actually have to classify them as fluids to start off with.

No, materials having the behavior that you describe above are not classified as fluids but rather as thixiotropic media. An example would be water-rich clays that upon undergoing a sufficient shear stress exhibit fluid-like behavior, but then quickly revert to a solid upon cessation of the shear stress. (An example are water-rich clays that become fluid-like during earthquakes.) This is a very different class of material than fluids.

However, skin, flesh, tendon, and bone, etc. are not thixiotropic media.

quote:

Does that mean I have been hunting elephant with a squirt gun?

Hi 500 Grains,

Over on the Small Game Forum they are hunting kitty cats with 4-inch diameter "ice cannons" so maybe you just need to freeze your water.....

Alf wrote:

quote:

Living tissues are solids.

Also:

quote:

When applying a stress to a solid ( compressive stress in this case) the solid deforms ( shows strain beahviour) and when the elastic limits of that solid is overcome it fractures.

Lastly:

quote:

There is no boundry layer behaviour, no flow so there can be no cavitating behaviour in the fluid sense in solids!

Then Don in Colorado wrote:

quote:

However, skin, flesh, tendon, and bone, etc. are not thixiotropic media.

I agree with that since I'm also skin, flesh, tendon and bone and never feels like a continuous shape changing plastic bag filled with some type of fluid called blood!

What is important here in my opinion is

quote:

....when the elastic limits of that solid is overcome it fractures.

Maybe the old, proven Newtonian Physics can help us here .

The acceleration/Action force from the fast travelling bullet is carried over to these solid fractures (fragments) in equal force amounts resulting in opposite centripetal forces curving away from the linear path of the intrusive object (bullet) and in following that path (fragments), causing the larger than calibre size permanent wound channel.

After all it is a force at work here brought about by the combustion process which came about when the trigger was squeezed in the first place.

And who would disagree with Newton's laws?

I had one Woodleigh 480 Solid, fired from my 450 No2 into a cow elephant from 6 yards, a quarting frontal brain. I was above her shooting at a slightly downward angle. The bullet exited the brain cavity and hit the spine in the neck. The bullet was flattened and the steel jacket was split.
It appeared like the bullet split when it hit the spine.
The other 3 Woodleighs I recovered from elephants and the ones from buff were not deformed.

Animals are not a homogenious medium.
First you have skin, this can be rather thick and tough on some animals. Then depending on where the bullet hits it might encounter bone [ribs]skull] or muscle [shoulder] then bone, then the fragile sponge like lungs, then a tough heart etc. Well you get the idea.
A bullet can become unstable as it goes from one substance to another.

All theories aside the ONLY way to tell what a bullet will due is to shoot game with it.
After shooting a lot of game with it you will have an idea of how it performes....most of the time.

.

NE 450 No2

quote:

All theories aside the ONLY way to tell what a bullet will due is to shoot game with it.
After shooting a lot of game with it you will have an idea of how it performes....most of the time.

Your comment is ultimately the bottom line. Shooting into all manner of building material, water, gelatine and yesterday's wet newspapers can only tell us how the bullet behaves. Once we know how the bullet behaves, under impact in a variety of media, we can make an educated guess at how it will perform in animals and testing must move to that stage. Once field tests show that the educated guess was correct, you have a bullet. We finally closed the file on field trials of a bullet this weekend after shooting another five animals with it. We now know how it behaves at close range, distance, on head shots, large animals, small animals, going way shots, broadside shots (breaking both sholders as well as high lung shots) and quartering shots. We launched this particular bullet last season, after the initial field trials showed no failures on 17 animals at a mv of 3600fps. This weekend it was taken to 4000fps and there were no surprises.

I stand sceptical of anyone who states that they developed "these five" bullets last night and "they really look good".

It has been established that flat nosed solids, with a straight line from meplat to shank, is the best balance between terminal performance and reliability in the rifle. Also established is the fact that terminal performance (depth, linearity, volume of wound channel) exceeds that of round nose solids and round nose solids with a flat section at the front.

These facts are supported all over this forum. How many failures have been reported with FN style solids? However, there are many tales of woe about the failures of round nose and truncated round nose solids, regardless of whether they are monos or jacketed. They turn, break at the cannelures, bend, squirt the lead out and generally behave in a less predictable manner than FNs.

Even when feeding in a particular rifle is an issue, our FNs do no worse than round nose solids. I have followed up on several reports of failures to feed GSC FN bullets and, invariably, the rifle is suspect.

Anyone who says that all solids are created equally and that it does not really matter which one is used, is disregarding the factual evidence gathered on this subject over the last ten years since we introduced the concept to DG hunting.

A thought: If the temporary cavity does no damage (or so little damage that it can be disregarded, according to some) what would be the cause of the broken ribs in the top two photos?

What do you mean by breaking both shoulders. I read about it all the time but never see it?

VBR,

Ted Gorsline

.

quote:

It has been established that flat nosed solids, with a straight line from meplat to shank, is the best balance between terminal performance and reliability in the rifle. Also established is the fact that terminal performance (depth, linearity, volume of wound channel) exceeds that of round nose solids and round nose solids with a flat section at the front.

I have read this general statement in several publications and threads within this and other forums and am willingly to accept this premise. I apologize in advance for my ignorance in asking this subsequent question, but do flat nose solids tend to shot materially different than more typical roundnose solids from double rifles and is there any problem with regulation, beyond just the need to work up a different reload formula?

Thanks

quote:

Originally posted by Don In Colorado:
...do flat nose solids tend to shot materially different than more typical roundnose solids from double rifles and is there any problem with regulation, beyond just the need to work up a different reload formula?

Don, I have worked with several powders, lots of different powder charges, different brands of brass, and many different styles of bullets in doubles. In the end I found that the load which regulated with Woodleighs also regulated with flat nose solids from Bridger and North Fork. POI was a little different, but not enough to worry about when hunting elephant. Vintage guns and high end European guns can be more picky.

quote:

In the end I found that the load which regulated with Woodleighs also regulated with flat nose solids from Bridger and North Fork. POI was a little different, but not enough to worry about when hunting elephant.

Hi Dan,

Thanks for the info. This is interesting. Although there would be big difference in ballistic coefficients I guess that since the time in the barrel is the same that the small velocity difference downrange becomes unimportant.

NE 450, I would bet the 480 grain WDL was going sideways when it hit the spine and may have split jacket when it hit the spine?

Have any of you folks like Norbert, Dan and Will who have shot alot of elephant ever had a bullet not get to the brain that was headed in the right direction to start with?

And do you all think that bonding the lead core of the WDL would help?

Andy

Alf,

quote:

What you are seeing in this picture is what the person who posted the picture wants you to see.

I thought that this was obvious as you made the statement "In the case of a cylinder or a projectile with a sharp cutting edge the permanent cavity is a cleanly cut channel equal to the outside diameter of the projectile." Norbert and I differ from you on this and Norbert posted the pictures of the wound channels created by flat meplat bullets. He clearly illustrated the fact that the damage caused by the passage of the bullets, exceeded the diameter of the bullets, by placing the bullets that caused the damage in the holes. Does it matter whether they are the actual bullets or bullets from the same batch? The point is made and nothing else is inferred.

Breaking both shoulders is a bad shot? On a Hartebeest or Blesbok, breaking both shoulders will also extensively damage the spine. There will be substantial tissue damage from all the bone fragments but that animal will not run. Having said that, I prefer broadside shots tight behind the front leg and low on the chest when hunting for meat. In all cases, breaking both shoulders with a properly stabilised mono bullet will result in an anchored animal. This goes for elephant as well.



My comment on shoulder shots also included high lung shots. Now that is one to avoid, however, I was not talking about general hunting but about what we think needs to be done to establish how a particular bullet behaves under varying field conditions.

Ted,
My mention of breaking both shoulders is that it often spells bullet failure when the nearside shoulder is hit and only very tough bullets will make it far enough and with enough poke to break the offside shoulder. As such we include it in our testing regime as we do quarter and full going away shots.

.

Let's see. If the average wound channel was 7mm, approxamately .284" and the SD was .23, then the 95% Confidence Interval was roughly 2 standard deviations or .284 + or - .46". That works out to -.176 to + .744 or 3/4". It appears that the small sample size of 10 has lead to a high variance. I think most of us would agree that a 3/4" hole from a .308 diameter bullet is significant and about what we would expect from a .308 diameter soft point.
While we do not know what type of bullet was used I suspect it was a full jacket military pointed bullet which we all know makes a small entrance and exit hole unless it tumbles. We are talking here of round nosed or flat nosed bullets and jumping from results of mil ptd. bullets to hunting bullets is a stretch that would not hold up in any scientific review.

465H&H

465H&H