Chris,
Your lengthy squirming above caused you to miss something (as usual) and it is there for all to see:

"Fortunately there are some design elements that escaped his attention and are not included in the bullets he produces."

Lutz's "patent" is on the drive band design, as is ours and that is what Gina referred to. It is right there in your quote. Let us see if the magazines you write for have the same cavalier attitude towards sloppy journalism as you, I suspect not.

Let's see now. According to your logic, a motoring magazine can do a comparison test between Firestone and GoodYear tyres and then state that Bridgestone tyres will produce the same results as the Firestones. Guns and Ammo can compare performance and service life of a Glock and a Browning HiPower and then state that FEG 9mm pistols (Hungarian clone of the Browning) will deliver the same performance as the Browning. After all, the Bridgestones look just like the Stones and Chris cannot tell the difference between the FEG and the Browning because we put tape over the names.

PS. Clover makes the yoghurt. Glover in JHB is a plumbing company. Lutz's bullet does not have a front core, it is a turned solid. If you ordered a chimp for your zoo and the supplier delivered a baboon, would you say: "OK close enough."?
PPS. You need to read some of the other threads then you will understand the coffin thing as well and, no it is not my place to edit the content of other websites.

All this leaves us with one unanswered question:

Bullet - MV - Retained Weight -- %
270gr - 2307 --- 266.2 gr ----- 98.6
286gr - 2252 --- 119.2 gr ----- 41.7

Which of the two bullets resulted in the deepest penetration and which bullet produced the largest wound cavity volume?

quote:

Originally posted by Gerard:

Bullet - MV - Retained Weight -- %
270gr - 2307 --- 266.2 gr ----- 98.6
286gr - 2252 --- 119.2 gr ----- 41.7

Which of the two bullets resulted in the deepest penetration and which bullet produced the largest wound cavity volume?

OK, I will take a guess. The 270 grain bullet?

500grains,
I suspect that you are right but lest we be accused of practising clairvoyance or failed psychic abilities, we should refrain from speculating.

When Chris confirms that the 270gr bullet did indeed perform better, I will be able to point out to him that this was because of the superior construction and speed of the lighter bullet and consequently, the higher retained momentum. I will refrain from mentioning that this proves the point that Sd is of little importance, other than that it added to the destruction of the heavier bullet, and I will not post these in that reply.

quote:

other than that it added to the destruction of the heavier bullet, and I will not post these in that reply.

I'll go out on a limb and say Sd had little to nothing to do with the added destruction of the 286 and apples/oranges construction differences did. I'd also speculate that after about 2" of penetration, the 270 had a higher SD because because the 286 had already lost a large portion of its weight and was likely a huge diameter.

Gerard,

Which do you think would penetrate more deeply:

9.3 mm - 270 gr. GS Custom FN at 2400 fps
9.3 mm - 300 gr. GS Custom FN at 2200 fps

Assumption: The bullets are fired from a 9.3 x 62 rifle, frontal shot on a cape buffalo.

500grains,
There would be little difference in the penetration depth between the two but given a Cape Buff, I would give the edge to the 270gr bullet. Here is why.

It would be better if both are loaded to full potential at 2550 and 2400fps respectively, in which case there would still be little difference between the two. In both scenarios the 270 gr bullet would have higher gyroscopic stability values, and shoulder stabilisation will be enhanced. This results in better linear penetration. Ke is higher with the 270gr FN and cavitation more likely, both contributing to a larger wound cavity volume. Recoil is less because of the lighter bullet and lower muzzle pressure, resulting in a more shootable rifle.

Both bullets are above the tensile strength threshold where retardation forces would cause the bullet to break and, although shooting through bone may slightly deform them, weight retention will likely be 100%.

Although the 270gr FN is 6c cheaper, you would spend that on more powder. (Some people ask about this.)

In every case the differences are small but added together, the 270 always has the edge. The same situation exists with the .416 380gr FN and the 410gr FN and in .375 with the 270 and 300gr FNs. Both work well but sometimes the edge is the difference between success and getting stomped on.

Posting for Chris Bekker:

Gerard and 500 Grains,

First of all I want to congratulate 500 Grains for guessing the answer correctly. This question surfaced no less than 6 times by Gerard. I have agreed to the request of RIP and BigRX that we bring this discussion/saga to an end. It seems you two guys have not had enough, but more importantly you guys just gave RIP and BigRx a flat-ignore and so invited me back with this silly question that I have already answered twice. I regret that I have to do it yet again. Just in case you don't know 500 Grains, Gerard left off in his posting that the 270 gr bullet has a 2 mm copper jacket, whereas the 286 gr bullet has a 1 mm jacket to create the impression we are comparing similarly constructed bullets.

Bullet - MV - Retained Weight -- %
270gr - 2307 --- 266.2 gr ----- 98.6
286gr - 2252 --- 119.2 gr ----- 41.7

Which of the two bullets resulted in the deepest penetration and which bullet produced the largest wound cavity volume?

My first answer was:

"You must be out of your skull to do it in terms of a discussion on sectional density (SD). That is the essence of the argument, so don't confuse the readers to create chaos out of order. Gerard please understand that we cannot compare SD's when bullet construction is not the same - so your insistence that I answer the question where we have a 1-mm vs a 2-mm thick jacket is ludicrous."

My second answer was:

"Your inability to comprehend what I have already explained to you is only surpassed by your inordinate stubbornness."

And now my third and final answer:

The 270 gr bullet with the 2 mm jacket was specially ordered by me, with no cannelure and a thicker jacket, to prove a point that construction plays a vital role. The 286 gr bullet with the 1 mm jacket had a cannelure that weakens the already thin jacket. Gerard you know this full well - you read it in my latest article that was published in the SA Hunter regarding "Bullet performance - stay within the performance band". Everybody knows my criticism against frangible thin- walled bullets that shatter with resultant shallow penetration - that is what I illustrated with pictures in the SA Hunter's magazine, and you saw it. It has absolutely nothing to do with SD - only construction and bullet design, and I spelled it out with no less than 4,500 words! I did these tests myself, I have the full facts and I can interpret what I have done. Gerard there is really nothing that you need to further explain to me - no need for a Rasputin to mesmerize me, keep it for your grand children. This debacle has now become a monument for all the readers to appreciate your obstinate mentality.

If SD plays no role, cut all your bullets in half so you can get 2 shots out of a bullet.
If SD plays no role, don't shoot bullets go back to ball ammo
If SD plays no role, go hunt big game with light bullets at hyper velocities.
We all know momentum is important, especially terminal momentum.
We all know construction is important.
We all know velocity interacts with construction and the threshold strength of a bullet.
We all know by now the interaction of Mo with Xsa.
We all know the relevance of controlled expansion bullets (CEB).
We all know that Solids have there place and role in dangerous game hunting.
We all know that HV bullets @ high velocity have their niche.

Just in case you don't accept the CEB concept, ask Alf the difference between a CEB and when a bullet behaves like a solid on Bison, we have not really discussed this one to death as with SD. Big lesson in there - see the thread 'Rhino bullets on buffalo'. (Old generation Rhino big bore bullets were not guided with a punch at the tip, and so they were tougher to open up on soft game). It seems two shots with a big bore solid (.423") have less effect than 1 CEB with a smaller caliber (.308") - very interesting indeed. Perhaps we should learn a lesson from Alf's experience (nothing beats experience).

Is SD everything? No it is not?
Is mass, velocity or momentum on its own everything? No it is not?
Is Mo/Xsa on its own superior over the foregoing? Yes it is?
Is Mo/Xsa everything? No it is not?
Is Mo/Xsa addressing the size of the hole? No it is not?
That is why caliber, and its expansion (CEB), by virtue of bullet construction and design, when combined with the foregoing increases the overall killing ability even though penetration is sacrificed - a balanced holistic picture without worshipping a single factor on its own.

Sorry guys there is really nothing to argue over any more.
Book a hunt and go enjoy yourself and buy your wife a present so she does not feel left out.

Cheers
Chris
Consider ... "NILS ILLEGITIMAE CARBORUNDUM"

/

Chris,
You underestimate the intelligence and depth of knowledge of the members here. Do you think anyone missed the fact that the 286gr bullet retained 119gr and the 270gr bullet at higher speed retained more than double that? It was patently obvious that one was of much tougher construction than the other. Only you could try and turn that into some sort of deception on my part.

As you say, you did the testing and you saw the results but once again you raise a smoke screen of deception. You have not answered the question until now and deceptively state that you have answered several times. Even now your answer is indirect, in the form of a congratulation, but it is accepted.

The rest of your rant simply repeats what you have said a zillion times before including the idiotic statements about half bullets, balls and shooting elephant with a 22.

You have said something similar to this several times: "we cannot compare SD's when bullet construction is not the same"

If I attach standard English definitions to all the words in that sentence, it then says that Sd is irrelevant as a parameter by which bullets of differing construction may be compared. Good, we agree on something.

In your tests with bullets of one type of construction you also found that penetration corresponded to within a percentage point with momentum. In those tests Sd, bullet length and bullet weight roughly followed the penetration trend. So what can we conclude about the relevance of Sd, bullet length and bullet weight from those tests? Maybe we agree on a second point as well.


Alf,
I would not even attempt to explain why penetration calculators do not resemble what happens in practice. Do you think they work? What did your numbers say is the projected penetration depth of the two bullets respectively? As a matter of interest and aside, what should the penetration of a 130gr 7mm bullet be at an impact speed of 3000fps, in a kudu, if no major bone is struck and weight retention is 85%?

Wound cavity volume is related to Ke. More Ke = more volume. So if the choice is between two bullets of similar penetration and general performance, the one with the higher Ke value will kill more effectively (ultimately the hole is bigger). Attempting to calculate the actual wound cavity volume would be an uncertain exercise as well as being pretty difficult to do. Best we can do is to use Ke as a comparison of likely events.

Now we all know that expending energy in the target has been a popular theory. So called energy transfer. It is a myth (and you know it ) and the reality is that the most effective mechanism with which to kill a living body, is a single large cavity as deep as what is required to destroy a vital organ or to allow it to bleed dry by sufficient (or complete) penetration. A single small cavity like the three in your Bison won't cut it and all the Sd in the world is worth squat if the bullet fails.

MacPherson puts it best (p7 Bullet Penetration): "Any attempt to derive the effect of bullet impact in tissue using energy relationships is ill advised and wrong because the problem cannot be analyzed that way and only someone without the requisite technical background would try."

/

Alf,
On the 7th of April I posted in reply to you:

"I do not know why the perception persists that MacPherson's book only relates to handgun bullets. His stagnation pressure tables go from 100fps to 6000fps. The bullet deformation/expansion section starts with pure lead projectiles at 770fps, through jacketed projectiles and ends up with steel projectiles at 6500fps. All the formulae he provides hold true for whatever velocity or other parameter you choose to plug into them. The title is after all "Bullet Penetration" and not "Handgun Bullet Penetration"

To this I must add that the work refers several times, where it is of importance, to the difference between rifle and handgun terminal ballistics. Do a deal with RIP for a copy and then we can discuss things from a different perspective. It remains the definitive published work on the subject and it is not Duncan MacPherson's work alone. He acknowledges the input and contributions of Dr Martin Fackler, Lt.Ed Fincel (head of the CHP Tactical Training Unit), John Hess (applied mathematics and fluid mechanics) and Dr. Walter Gelon (aerospace engineer).

For a further perspective and information that is firmly grounded in good science, HTL's site cannot be surpassed.

(RIP, the person I mentioned that was looking for a copy of Bullet Penetration has found one.)

Alf, run the numbers for the 7mm I mentioned above by the penetration calculators and let me know what the outcome is. Reality for this example can be found here. You can conclude for yourself if they correspond or not.

In my post to you above I asked for some information and you chose to ignore it and plough forwards with some pretty erroneous statements. If we are to have a civil discussion here you might want to slow down and interact. I do not ask loaded questions (except when debating with Chris) and if my questions/feedback are ignored there is no point in continuing. I would like to know what numbers your calculations came up with and what parameters you used for the calculations. If you treat me like a moron, I cannot discuss ideas with you.

Chapter 2 of Bullet Penetration is titled "Understanding Energy Relationships". It discusses precisely the reasons why I say you came up with erroneous statements. In the summary of the chapter is this: "Attempts to determine bullet effectiveness or assign wound trauma incapacitation by assessing bullet kinetic energy are doomed to failure for two interconnected reasons:
1) damage is done by stress (force) not energy.
2) an indeterminate, but usually large, amount of the bullet kinetic energy leads to tissue stresses that are not large enough to cause trauma (especially in handgun loads).

On the subject of energy transfer it is very clear that only thermal energy is transferred to the target. Both the kinetic energy and momentum of even the most powerful rifle bullet can be absorbed by a 180lb animal (man) without damage if it is received apropriately.

Regarding lighter bullets being more effective than heavier ones and specifically the 9.3 and 416 FNs: I relied on comparative tests done by Johan Calitz' outfit for guidance on what happens in reality. His feedback was that the 270gr 9.3 is better than the 300gr FN and that the 380gr 416 outperforms the 410gr FN. This was done in the early stages of the development of the FNs in 1997. Shall I call him and tell him his observations were incorect? Since then I have been fortunate to also have the input of Jaques Greeff, Francois Strydom and Charl Du Plessis for comparative work on dangerous game.

Everything always came down to one fact. Given similar momentum values, a cylinder shape with more Ke will outperform another with less Ke every time. How does your penetration calculator explain a complete lengthwise penetration of a blesbuck with a 40gr HV bullet at 200 metres? Mv was 4400fps. How do we explain shooting a 540gr .510 bullet clear through a Cape Buff with a 500NE on a going away shot? A 500gr FN from a 500 Jeff hit an ele on the right rear leg and winds up in the left tusk nerve? Think back on the performance of the 130gr HV bullet on game you shot with it and then plug those results into the calculators. There are forces at work that interact in ways that cannot be modelled by current methods.

I am not a mathematician (I have to employ them) and have relied heavily on field proving new designs extensively. Like it or not, our FNs and HVs have broken new ground and there is still a long way to go before we understand everything (if ever) about what is happening.

Alf,

One of the reasons I would expect the 270 gr. to penetrate deeper than the 300 gr. is that most 9.3 rifles do not have a very fast twist, and the 300 in a monometal design may not be well-stabilized. Correct me if you think that is incorrect.

Which of the following would penetrate more deeply:

9.3 mm 300 grain GS FN solid 2400 fps
9.3 mm 320 grain Woodleigh FMJ RN 2200 fps

My money is on the 300 grain for 2 reasons: (i) FN design, and (ii) better stabilization. As for the FN design, I buy into Norbert's supercavitation theory, and more velocity tends to mean more supercavitation.

/

quote:

Originally posted by ALF:


The chinese have done it, I actually have a reference to an article done by the Cinese on the simulation of a human ballistics model where all the factors such as bone etc are calculated in.

Then why do their cops carry 32 acp handguns?

/

quote:

Originally posted by ALF:

Why 32 Acp's, cause there is very little or no crime, likely they do not need any firepower.

They have plenty of crime. But the crime is primarily committed by the government.

The US used to import Norinco stuff, so we saw absolute crap 1911's, M1A's, etc. Maybe they improved the quality since then.

500grains,
Gyroscopic stability, shoulder stabilisation and the position of the centre of gravity of a bullet when in the terminal phase is important. All can ad to or detract from linear penetration. How much does each contribute? Who knows, I don't. As for doing the math, I have not been able to find reliable methods to predict things when it comes to terminal ballistics, shooting game. When dealing with absolutes (what is going to happen if I use X projectile constructed of Y material to impact at 4000fps on 30mm Bohler K110 hardened and tempered to 45Rc), math is useful. The purpose is singular - punch a hole or knock it over, whatever. When dealing with game and field situations, I fall back on making some basic estimations and calculations to arrive at a starting point and then go hunting. Ultimately, when you see the results of several dozen carcases shot with two or three variants of a bullet, the direction the design should go becomes evident.

External and internal ballistics is a walk in the park compared to terminal ballistics. Here one can calculate very precisely with great accuracy as to the outcome of things. Terminal ballistics is such a dynamic event, the variables drive me nuts.

So what is the reason for the superiority of the 270 over the 300 in 9.3? (Bear in mind I said there is little difference but the 270 has the edge.) I can only repeat what I have already said above. This is what has been observed. Regarding the 300gr FN compared to the 320gr Woodleigh, the gyroscopic stability of the Woodleigh would probably be higher than the FN. The FN, being pure copper, would be the length of a jacketed lead bullet of about 350gr. The FN would have a CG that is further forwards than a RN jacketed bullet and it would have the advantage of shoulder stabilisation and cavitation. Nose shape also plays a role in how the permanent and temporary cavities are formed. So how do we calculate all this? Like RIP, I run screaming from the problem, pack the hunting gear and go find out. (Or send some to an associate who understands what we require by way of testing on game, observation and feedback.)

As an aside, I used to build race guns for Practical Pistol shooters and the Norinco 1911s we imported were of very high quality. The preferred slide on a wide body Para Ordnance or McCormick frame was a Norinco. The only ones I ever saw that cracked, were those that were hard chromed and the same happened to the Colt, Springfield and other slides we used. The Norinco parts always gave better mileage distance. These photos are of work done before Norinco became available to us.

Alf,
By civil and interact I meant that when you make a statement and I ask a question based on that statement, I expect an answer or at least some acknowledgement that one will be forthcoming in due course. That is being civil and is what I attempt to do. There is no point in raising several new issues before others are dealt with. We have seen that doing it that way takes 7 pages to resolve simple issues. Now I would like to know:

"What did your numbers say is the projected penetration depth of the two bullets respectively? As a matter of interest and aside, what should the penetration of a 130gr 7mm bullet be at an impact speed of 3000fps, in a kudu, if no major bone is struck and weight retention is 85%?"

Once I have this information, we can continue to other points you have raised, one at a time. I cannot herd cats.

/

Gerard,

The Norinco 1911's that showed up here in the U.S. had astoundingly poor workmanship. They rattled like a bucket of bolts (much worse than a WWII military 1911), they had 12 pound triggers, accuracy was very poor, and stamping and machining were rough. The going price was about US$250 when Springfield 1911's were about $400.

___________

Alf,

Is there a noticeable difference in effectiveness between a 7.62 x 39 and 7.62 mm Nato on human targets?

Alf,

quote:

I have put those figures to the math and in 3 different mathemamtical penetration calculators and in none does the 270 gr outpenetrate the 300 gr bullet under the given parameters for a pure flesh wound, any comment?

quote:

According to my calculations your 270 gr FN bullet will overtake the 300 gr bullet when the 270 gr bullet is fired at around 3100 fps

OK leave the 130gr on the kudu be. I will settle for the results you obtained above.