While we are waiting, I want to know from you:

Take two bullets of the same caliber and the same weight, say 450gr FN bullets, and shoot one at 2100fps and the other at 2400fps. Which one penetrates deeper and why?

My aplogies to those who know what is coming but you see the situation. It is almost 3:00 am here I am turning in now.

quote:

Originally posted by Gerard:
You want to dance? Lets go.

The heavier bullet penetrates deeper. Tell me why.

and you have anything else to say?

interesting that you now abandon your position that SD means nothing.

Night gerard... go take a customer service class

jeffe

Jeffe,
Two possibilities here:
You really are stupid and have trouble reading and comprehending or you are a coward and you cut and run with that inane reply.

Either way suits me but it would have been nice to whip your sorry butt.

.

Finally! You have come around to the truth!

quote:

Originally posted by Gerard:
Jeffe,
Two possibilities here:
You really are stupid and have trouble reading and comprehending or you are a coward and you cut and run with that inane reply.

Either way suits me but it would have been nice to whip your sorry butt.

Or Gerard,
You are incapable of understanding that no one but YOU agree with YOU...

this is called mental masterbation...

You said initially, in this thread, that SD had NOTHING to do with penetration. Then said in answer to my question, that the heavier bullet would penetrate further than the lighter one.

A heavier (same caliber) bullet has a higher SD.

You loose....

btw, I am begining to get a little concerned with your fascination with my ass... If that's your thing, well, you go to it... it aint mine, so the answer is NO

jeffe

Alf,
Nowhere in your post do we see Sd described with the term Sd. Probably because the author knew that it is a non-entity. We see the elements that make up what Sd is supposed to be (sort of), as we see the individual elements that make up momentum. Even the elements for Ke are there, as are the elements for cross sectional area. To go back to the graph, you must surely see that it functions as a whole. Remove one or two elements or look at them in isolation, and the whole ceases to function. Saying that m/R implies that Sd is a factor, would be the same as saying "see the lines denoting speed" and touting speed as the driver of penetration depth.

As RIP says, the truth at last. An indicator of penetration must contain three elements. Weight, speed and frontal area. This is a basic beginning because these elements must then be adjusted with other factors, as you pointed out, to arrive at R in the equation.

No one can take a gander at the likely penetration of a bullet if one considers only speed or weight or diameter. Neither will momentum or energy or cross sectional area or Sd be any indication if used on their own. Three elements are required to make up the whole and without speed there can be no indicator. My example of two identical bullets at different speeds proves just that.

Pardon me I have to go tend to kindergarten class.

Jeffe,
A heavier (same calibre) bullet has a higher Sd more energy and more momentum. So which makes it penetrate better?

Now answer my question above. For clarity here it is again: "Take two bullets of the same caliber and the same weight, say 450gr FN bullets, and shoot one at 2100fps and the other at 2400fps. Which one penetrates deeper and why?

Jeffe,
Knock it off! Your ass is showing! Do not further em-bare-ass yourself, and your countrymen by association. We will disavow knowledge of your citizenship if you do.

quote:

Originally posted by Gerard:
Jeffe,
1: A heavier (same calibre) bullet has a higher Sd more energy and more momentum. So which makes it penetrate better?

Now answer my question above. For clarity here it is again:

2: "Take two bullets of the same caliber and the same weight, say 450gr FN bullets, and shoot one at 2100fps and the other at 2400fps. Which one penetrates deeper and why?

Gerard,
As usual, you are mixing issues.
For clarity's sake, I have broken this into 2 easy for gerard to understand items... simply "1 and 2"

1: To answer your question, gerard... Energy and Momentum are factors of weight and vel. If you change the VEL, the energy and momentum change, but the SD is a CONSTANT over all of the potential questions in that environment. Energy and Momentum AINT. In fact, gerard, speed, mass, and diameter (of a known construction) are the ONLY primary facts. Everything else is a function of those three.


2: Assuming that you have a known and constant material (the bullet) velocity (Speed), and SD (mass and diameter)and that the material doesn't ablate, the faster bullet, will penetrate deeper. Why? which units are you prepared to argue against? it's a generic "WORK area under a curve" with the axis being depth and any non-primary units you with to arbitrarily use to define "work"

Wow,
finally you made a post there you didn't post softcore pics of ass's, talk about wanting to dance, or wanting to do other things with my ass... NO means NO g

jeffe

quote:

Originally posted by RIP:
Jeffe,
Knock it off! Your ass is showing! Do not further em-bare-ass yourself, and your countrymen by association. We will disavow knowledge of your citizenship if you do.

Ron,
Hmm, interesting... Didn't know you are a texan to revoke my citizenship.


Tell me EXACTLY where it's incorrect that a higher SD bullet, of the same construction and velocity, will not penetrate more?

As this is exactly what G says, further in this post

Gerard's here trying to say SD (bullet mass and diamter) have nothing to do with penetration...

and then turns right around and states that a heavier in caliber bullet, at the same speed, will penetrate deeper, AEBE... which says that a higher SD bullet will penetrate deeper, by his own words.

.

quote:

Originally posted by jeffeosso:

2: "Take two bullets of the same caliber and the same weight, say 450gr FN bullets, and shoot one at 2100fps and the other at 2400fps. Which one penetrates deeper and why?

2: Assuming that you have a known and constant material (the bullet) velocity (Speed), and SD (mass and diameter)and that the material doesn't ablate, the faster bullet, will penetrate deeper. Why? which units are you prepared to argue against? it's a generic "WORK area under a curve" with the axis being depth and any non-primary units you with to arbitrarily use to define "work"

jeffe[/QUOTE]

CAREFUL! Remember the old adage containing in part: "Fooling most of the people most of the time ......Then ending: ..... but not all of the time?"

Narrow your parameters (or expand them) or this could give you the answer you desire; . . .or the one you don't...

BigRx

quote:

Originally posted by jeffeosso:

Tell me EXACTLY where it's incorrect that a higher SD bullet, of the same construction and velocity, will not penetrate more?

Bottom line is you haven't been told as of yet jeffeosso!

Lots of dancing around and flat out diversions like SD being based on a square bullet!
Let's hold that thought a moment!

Maybe we see the SD of any description IS NOT IN THE FORMULAE PER SE IN EITHER THE SQUARE OR ROUND VARIETY.......OR IS IT?

I am impressed with the knowledge on this thread! Even more so, the ability to think on ones' feet! I would like to keep all of you talking......... So I have a few more questions:

1. What is the terminal difference between a deforming and non-deforming bullet into a test medium?

2. When a bullet deforms to a frontal area, what happens to its SD? What happens to penetration if all else is constant?

3. If the bullet then continues to expand to a larger frontal area (over time!) then what happens to its SD? How is penetration effected?

4. Is not SD a reliable guide them, using this "mushrooming example" comparison?

5. And last but certainly not least! If our frontal area is square shaped (very possible these days!) at a given point of penetration is it then OK to calculate using a "square bullet" formula ?

Thanks for your imput.... Don't bow out jeffeosso, ALF, Gerald, Chriss, or anyone else I missed!

BigRx

Jeffe,
I am mixing issues? Do you now have a problem with more than one concept at a time?

You made the statement: "A heavier (same caliber) bullet has a higher SD." to which I added "and also more momentum and more energy."

You cannot deny that it has more momentum as well as energy. My question is therefore very simple and does not require an answer of a thousand words and the dragging in of "all of the potential questions in that environment".

In your opinion, which of the three factors, higher Sd or more energy or more momentum makes the bullet penetrate deeper?

So as to steer clear of the problem of mixing issues we will deal with question 2 only once we have settled question one.

(Interestingly you say "speed, mass, and diameter (of a known construction) are the ONLY primary facts. Everything else is a function of those three." See my reply to Alf above your post where I state: "An indicator of penetration must contain three elements. Weight, speed and frontal area.")

BigRx,
What is your take on "Take two bullets of the same caliber and the same weight, say 450gr FN bullets, and shoot one at 2100fps and the other at 2400fps. Which one penetrates deeper and why?"

Of course we assume that there is no deformation of the bullets and we start with two identical bullets.

[qoute]Originally posted by jeffeosso:
Tell me EXACTLY where it's incorrect that a higher SD bullet, of the same construction and velocity, will not penetrate more?

Bottom line is you haven't been told as of yet jeffeosso![/quote]

This has been asked and answered several times. You cannot deny that higher Sd also means more weight. More weight x the same speed = more momentum and that is why the bullet penetrates more because all this leads to more Mo/XSA.

This must be settled and agreed upon before we can hope to move on to the rest of a discussion. If we do not do so, the chain breaks down further along and we start over, as we have done several times. (Alf, you still there? )

See this article. If you find the first section irrelevant (and it is) skip down to the picture of the animal with a target painted on it.

quote:

Originally posted by Gerard:
You made the statement: "A heavier (same caliber) bullet has a higher SD." to which I added "and also more momentum and more energy."

...

You cannot deny that higher Sd also means more weight. More weight x the same speed = more momentum and that is why the bullet penetrates more because all this leads to more Mo/XSA.

This must be settled and agreed upon before we can hope to move on to the rest of a discussion. If we do not do so, the chain breaks down further along and we start over, as we have done several times. (Alf, you still there? )

See this article. If you find the first section irrelevant (and it is) skip down to the picture of the animal with a target painted on it.

Gerard,
you astound me with your "explainations".. a bullet at zero relative speed has zero momentum... and still has an SD...

wild example?

Nope.. just a fact... SD exists without velocity. momentum is an product, not a primary.


I give up trying to talk with you, as you obviously can't admit that you mixed elements and want switch to explantion rather than penetration.. penetration was chris's point.

Here's a great quote from your article

"Although all three once had the same sd, the more they deformed, the better they worked and the worse the sd became"

substitue "expanded" for worked, and you have it right...

jeffe

Could all of this be defined like this....

A bullet with a higher SD has a greater POTENTIAL to pnetrate than one with a lower SD with ALL other things being equal. But a bullet with higher MOMENTUM will penetrate better than a bullet with lower momentum with all other thing being equal, without regards to SD. In othe words with two bullets on the table and one with a higher SD, all other things being equal, the higher SD bullet has a greater potential to penetrate, but since neither has any MOMENTUM neither will penetrate as that is the driving force. Is this a good way to look at it, or am I still missing something?

Jeffe,

From my post above:

"You made the statement: "A heavier (same caliber) bullet has a higher SD." to which I added "and also more momentum and more energy."

You cannot deny that it has more momentum as well as energy. My question is therefore very simple and does not require an answer of a thousand words and the dragging in of "all of the potential questions in that environment".

In your opinion, which of the three factors, higher Sd or more energy or more momentum makes the bullet penetrate deeper?"

Simple question. Why can you not answer?

You employ strange logic. In the article the caption to the picture reads: "Although all three once had the same sd, the more they deformed, the better they worked and the worse the sd became"

And you reckon that changing it thus would be closer to the mark?

"Although all three once had the same sd, the more they deformed, the better they expanded and the worse the sd became"



Neverflinch,
Bingo! Your statement cannot be faulted and is precisely what I have said since page one. My second post, where the practical ability of the bullet to penetrate was the issue, contained: "I made the point that SD is not a good indicator of the penetration ability of a bullet. My opinion is that bullet construction, energy and mainly momentum are the real indicators."

My problem is with those who look at a lead core bullet (30 cal 200gr) and say to me they prefer it over a 30 cal 160gr monometal bullet simply because it has more Sd. Or the person who says he prefers a heavy bullet (within a same bullet scenario) because it will penetrate better, without taking any other factor into account. This misinformed opinion is fostered by decades of harping on the importance of Sd as the indicator where it is not. As with many other common fallacies we must start an education process that will better equip us to make better decisions and draw more precise conclusions.

.

So where do we go from here, maybe after all and after what 5 or 6 pages we still contend that a bullet's mass in relation to it's derived or approximated flawed and in error frontal area is of no consequence...... Hmmmmm methinks not ?[/QUOTE]

Pretty simple, at least to my eyes.

From Sierra's manual

1) The second way to describe the BC is to use its precise mathematical definition.

Mathematically, the BC defined as is the sectional density of the bullet divided by the form factor.

This definition emerges from the physics of ballistics and is used in mathematical analysis of bullet trajectories.

But in a practical sense, this definition is not satisfactory to most people for at least two reasons. The first is the question of a bullet’s form factor.

The form factor is a property of the shape of the bullet design, but it is no easier to explain than the BC.

The second reason is that this mathematical definition can lead to an erroneous conclusion.

Assume for the moment that the form factor is just a constant property of the bullet design (not always true).

The sectional density of a bullet is its weight divided by the square of its diameter. (The square of any number is the number multiplied by itself).

So, to get a large BC we need a large sectional density. It appears from the mathematics that a bullet with a very small diameter should have a very large sectional density because its weight is divided by a very small number, and this should give it a very high BC. In other words, this line of reasoning would lead us to expect that small caliber bullets should have very large BC values.

But this is not true because when the diameter of the bullet is small, the volume also is small.

The weight of the bullet then is small, and the sectional density is necessarily small also. The net result is that small caliber bullets generally have lower BC values than larger caliber bullets.

2) The original issues is if SD is related to penetration

3) From #1 it is clear why the IMR tests ranks so high SD, because it means mass and it is pretty obvious why it's related to MV and pressure, in other words to interior ballistics

4) The rest of the arguments are easily derived from the foregoing

Again, as I understand we were discussing the original post regarding the relationship between SD and penetration, and I'm afraid we are offroad...

quote:

Originally posted by Gerard:
BigRx,
What is your take on "Take two bullets of the same caliber and the same weight, say 450gr FN bullets, and shoot one at 2100fps and the other at 2400fps. Which one penetrates deeper and why?"

Of course we assume that there is no deformation of the bullets and we start with two identical bullets.

[qoute]Originally posted by jeffeosso:
Tell me EXACTLY where it's incorrect that a higher SD bullet, of the same construction and velocity, will not penetrate more?

Bottom line is you haven't been told as of yet jeffeosso!

This has been asked and answered several times. You cannot deny that higher Sd also means more weight. More weight x the same speed = more momentum and that is why the bullet penetrates more because all this leads to more Mo/XSA.

This must be settled and agreed upon before we can hope to move on to the rest of a discussion. If we do not do so, the chain breaks down further along and we start over, as we have done several times.
[/QUOTE]

mo-men-tum\: a property of a moving body that determines the length of time required to bring it to rest when under the action of a constant force or moment.

Mo/XSA..........

Gerald,

I have read these entire five pages again. I have read your attachment as well with interest.

Momentum is a "sometimes" thing for even estimation, must less a good accuracy of penetration in all aspects. The results can vary and if "variables" are left out even erroneous!
Please don't hear that momentum and the formula are wrong! Please don't read that SD is the answer either!
Either can be "swayed" to prove a point such as heavy non-deforming bullets at relatively close together impact speeds; but I think we all really want a mathmatical indicator of penetration if possible; but this is hard!
BC isn't ALL it; Mo/XSA is not our huckleberry either all the time....

I have the benefit of being a penetration impact statistic nut! I have tested many mediums of which living tissue is one. I have learned a few things......... So I compare what is written here to experience to "weigh" its truth, ... or better put its accuracy across all parameters...

Shooting the weighed cylinders in your article is a momentum test if there ever was one!Pity that pushing a Cape Buff hard enough from impact to do lasting damage may in fact hurt us the hunter more from the recoil of what would be required!!
The wood tests are great for straight-line penetration look sees; and a good indicator of stabilization (i.e. rifling twists) another fantastic subject!
And then your hypothetical self-healing animal at 50 paces! Ahhh! That we could only have such a convenience! We will use this guy in a moment with his ability to remove all the variables at impact to test out our theory!! ???????

Alf has flirted around with some good stuff I must admit.

But we are consumed by the dynamics of the bullet! Are we blinded to some of what we need in our equation?

Back to your article and the three bullets...
This and our contributor jeffeosso has put a way that may explain what I try to get across here; the thought that momentum or SD cannot be trusted in entirety across the range we would like it to work in....

jeffeosso stated to change "worked" to "expanded". Hummm? I don't have a problem with that..... that puts the emphasis on the bullet! But then your word is good too! "worked"... This refers to the bullet's accomlishments in water and maybe even our hypothetical animal? The only thing wrong with the statement in my eyes was a lack of completion. i.e.: "worse the section density became and the less they penetrated."

So what are we missing then to accomplish this from the keyboard in lieu of reality?

Let's quote some RIP: "BAM! (formula for round bullet) ....momentum.......

"BAM!" is the report of our gun. We have two guns firing as one sound. We have two identical Gerald EXACTLY EQUAL animals at 50 paces. One gun has a light (lower SD) bullet, the other gun has a heavier (higher SD) bullet, and both are the same caliber. There MOMENTUM is exactly the same and their velocity differental is maximized for a clearer view of our scenerio; using the lightest bullet at the fastest speed vs. the heaviest the twist will allow while keeping momentum identical as already stated.

After our superimposed "BAM" what do we hear?

"Whoop!Whoop!" The two impacts; one ahead of the other. We will disregard the time of flight that caused this. (ALF has good points and "air time" can teach us a lot about a bullet's terminal effects.) But we will now talk time beginning at our moment of impact for each load each in its own sequence of events.

Our momentum numbers equal to the fraction have made us forget that the momentum was derived by different variables to accomplish having a common number. But we can't forget the distinct characteristics of each entry or we have overlooked variables!

Our hypothetical twins of flesh are absolutely identical! I want to add an item now. Another variable overlooked. Let's call it "RTD". "Resistence to deformation" Not our bullet, but our hypothetical animal itself!

Our light bullet makes contact with every bit of the momentum of its slower cousin mere feet away from impact.... Mr. Light is fast! He covers more distance in initial penetration for a given time in milliseconds. What does our exact hypo animal do because of this? He resists this faster inital movement with more resistence! ( I suppose one could take their body weight and velocity doing a belly flop into a swimming pool from six feet with weight added with a belt to equate momentum of a like belly flop off the 10 meter high board to somewhat understand what our lighter bullet goes through for a brief instant! This with the same identical water or flesh.
This extreme first few inches suck momentum from the fast light projectile like a sponge! It will probably penetrate less with similar bullet construction. This is not all bad... While it slows very fast the "trauma" area around it is damaged more! Bullet makers tend to strengthen, use higher tensile strength materials, monolithic construction and other ways to allow the bullet, the high velocity bullet to "get through" this "compressed area" of RTD that relaxes along with impact speed reductions. THIS IS WHY THE NON-DEFORMING BULLET IS SUCH A GOOD EXAMPLE!It "blasts" through this area of high "RTD" with a small frontal area still intact and seems to follow the Mo/XSA as a rather good example!

I guess with all due respects to all I will summerize that mathmatically we have a hugh task to formulate exacting penetration results; even close estimates being difficult. Wet packs, and whatever else we can dream up for simulation knowing even a close match still will exhibit RTD and maybe not as uniformly as real flesh compounding variables maybe beyond our control. SD, Mo/XSA only tools to help estimate a much more complex answer that we probably really know.

BigRx

BigRx,

I agree 100% with some of your remarks.

As stated before, the phenomena involved is very complex, and to my knowledge, the only serious studies available are based on observations as well as finite-elements analysis.

I'm sorry to sayt that no simple model is available...

However, we can discuss factors that help a bullet to penetrate better, in fact many of them do not need a lot of explanation, for example mass, materials, construction, etc

Twizzlers OR Redvines????????

Alf,
Finally we are getting somewhere.

Those are interesting references you have and of course not really relevant to terminal ballistics. Looking at how Sd fits into the big scheme of things, regarding internal and external ballistics, it once again tags along as part of a bigger picture, as it were. In this case as part of the description (SD and the bullet's shape) for BC. In all, the real role of Sd is simply to say that, in a given equation where weight and frontal area occur as elements, that part of the equation is expressed as Sd. And even then the elements are corrupted because of the imprecise formula for Sd which then detracts from the accuracy of the equation.

May I suggest that where Sd is at the top of the list (IMR Tests), the better contender for that position would have been Inertia. But as Gustavo says, we digress although in an interesting way.

Getting back to terminal ballistcs, BigRx points out the very real problem of what happens in the small space of time from when the bullet strikes till it stops or exits the target. To determine precisely how a bullet will react in that environment through calculation is impossible I think, as there are variables we have not yet touched on and RIP put it best. One runs screaming from that problem.

In what I do, the best I can hope for is to get close to a solution through calculation and testing in artificial media and then to go out and shoot animals. Of course this field testing would be realistic and appropriate as I would not take my 22x64 after an ele or the 375H&H after a springbuck. In both cases the result will be so predictable that it would prove nothing.

The pages up to this point would also be of zero interest to the vast majority of reloaders and hunter/shooters. Like me, many of them are mathematically challenged and rely on those with the schooling in the various subjects to crunch the numbers and "do the math".

This brings me to two very important moral responsibilities: I must not mislead and I must not pretend that I know.

To this end, I believe that it is futile to tell someone that the Sd of a bullet is "X". It is also futile to rely on muzzle energy as a guideline for terminal performance. Alf, check any reloading manual you like, that bit of folly is also still with us, despite being a very minor part of the big picture like Sd. So if we come full circle, Sd and ME are supplied by the manufacturers because it is demanded by the uninformed. The big numbers sell, regardless of whether they are of value or not. What do we put in their place to serve as guideline and information? If Mo/XSA will not suffice, something better will evolve, but the uninformed will demand that it be simple and understandable and no one should have a problem with that.

Much of this thread, and of the old references supplied by Alf, most recently above, is beating around the bush. Mental masturbation.
Why do we have to convince ourselves of anything other than the basic, undeniable facts that it all starts with bullet mass, velocity, and caliber. That's it, that's all.

SD is a mental crutch. Easy shorthand. Proportional to reality, a ratio, a FOM. It is not useless. Stating a sectional density is just a simple way of describing the potential ability of the bullet to generate momentum that will not decay away easily once the bullet gets moving. Because if the SD is high, then the caliber is small, or the bullet is long and heavy relative to the caliber.

So a high SD indicates a relative ability of a bullet to have a high ballistic coefficient (independent of any streamlining form factors), or to have a great momentum and inertia to keep it moving once it gets moving and starts encountering resistance.

But really it all starts with mass, velocity and the size of hole that the non-expanded bullet makes. Then the complicating factors start, like "sectional density," which must be admitted to contain some BS.

There is no BS in Mo/XSA.

.

quote:

Originally posted by RIP:
But really it all starts with mass, velocity and the size of hole that the non-expanded bullet makes. Then the complicating factors start, like "sectional density," which must be admitted to contain some BS.

There is no BS in Mo/XSA.

Rip,
Let's look into EXACTLY what you just said.

Mass, Vel, Caliber..
500 0 .458

and what's the BAM! of that?

okay...
Mass Vel Caliber
700 0 .550

and the bam of that ????

What? No BAM!?
No way to compare them other than "wow, the bore is bigger?"

Hmmm, i wonder what's the only "mental shorthand" to compare those two bullets?

hmmm...

oh, SECTIONAL DENSITY
.341 and .331, in these cases

jeffe

You fellas have been having way too much fun in my absence.

I love ratios. Non-dimensional entities, full of sound and fury, signifying nothing.*

* In and of themselves. Much like my Ex.

quote:

Originally posted by RIP:

But really it all starts with mass, velocity and the size of hole that the non-expanded bullet makes. Then the complicating factors start, like "sectional density," which must be admitted to contain some BS.

There is no BS in Mo/XSA.

Are you sure about this RIP?

Let me tell you a story because I sometimes learn more away from this keyboard that I do at it!

One fall I had an unfilled deer tag. I live deep in the country with one neighbor about a half mile away.
My morning coffee dribbled down my chin as I saw a fat mule deer buck eating frozen remanents of zuchini in the middle of my garden!
I grabbed a 1911 Colt .45 ACP as it was handy as well as loaded. I went out the front door and circled the house quietly.....
When he looked up I "planted" a .45 a couple of inches under his chin........ He wilted like the frozen squash below.......
The animal: The neck was broken in the lower cervical area. I was careful dressing out as I wanted the bullet! I was behind the diaphragm still following the hole. Gad! It went out the back of the left ham in a small un-traumatized hole! It had broken the neck, penetrated three feet and exited! The line of penetration was straight as an arrow.... Could it be the 1 in 16" twist when old man Greenhill says the twist should be in feet? A message here, African hunters..........

The load: A 195gr hard cast semi-wadcutter handload with a muzzle velocity of 950fps!

The bullet dynamics: Diameter: .452 SD .174 Dreadful! Momentum: 26.46 Humm?
And last but certainly not least:
Mo/XSA 164.9! WHAT!!!!!!!!!!

The animal's dynamics: "Oh this doesn't matter!"

OR DOES IT?

BigRx

Alf,
Don't get bent out of shape now. The articles you referred to are certainly relevant to their various subjects and given the time frame they were written in, representative of the thinking at the time. Given that we still think today that terminal ballistics is an inexact science, what would the measure of inexactness have been 30 or 35 years ago? Surely we can accept that, where all sectors of technology have taken vast strides in the last ten years, our area of interest must have done the same given the passage of three decades.

I am glad to see Chris is contributing again. Alf, how come you have a connection to sector three of the Delta Quadrant?

Chris,
Your post makes a lot of sense and clarifies a number of things. There is just one area where you are dead wrong.

"In this regard I also need to mention that when a bullet's petals that sheer off before it reaches the vitals, due to high impact velocity, is therefore far less desirable, and that goes for all bullets, including Barnes-X."

We have been skirting around the deformed bullet shape. The long and the short of it is that a mushroom shape is less effective at causing trauma within the wound channel than a cylinder shape. This means that a caliber size cylinder at similar speed to a same calibre bullet, that mushroomed to 1.5x diameter, will produce the same size hole at handgun velocities. As speed increases, this effect is enhanced to the point where the temporary wound channel will contribute much more volume to the permanent (crush) cavity than the crush cavity itself. See the pictures of the springbuck with 1.25" hole made by a .224" cylinder.

At the same time, resistance to penetration is less than that of the mushroomed bullet so that speed and penetration are also sustained for a longer period of time. See BigRx's experience above. Another contributor to AR reported in tests he did, that FN style bullets at rifle speeds (2000 to 2400 fps), had similar destructive effects as softs at the same speed and in the same media.

Jeffe,
When you have determined the Sd of your two bullets with no BAM, what would you do with that knowledge? They are both just sitting there with no BAM and not going anywhere. I suggest you load them up and pull the trigger on them and instantly make Sd irrelevant with BAM. I have this mental image of two bullets all polished up and each wearing a little card on which is written the Sd. Every time you walk past I can see you marveling at the two pretty little bullets all dressed up and not going anywhere. Yup, little Sd .341 and .331 just sitting there looking pretty.

BigRx,
You had two things going for you on that deer. Two factors that are very much underrated and improves terminal performance much more than what is thought. Bullet nose shape and a twist rate far in excess of what is required. Be assured, some of us African hunters have noticed this.

Gerard,

Please get back to the shop and make my bullets instead of conversing with these blokes.

quote:

Originally posted by Gerard:
....
Jeffe,
When you have determined the Sd of your two bullets with no BAM, what would you do with that knowledge? They are both just sitting there with no BAM and not going anywhere. I suggest you load them up and pull the trigger on them and instantly make Sd irrelevant with BAM. I have this mental image of two bullets all polished up and each wearing a little card on which is written the Sd. Every time you walk past I can see you marveling at the two pretty little bullets all dressed up and not going anywhere. Yup, little Sd .341 and .331 just sitting there looking pretty.

Gerard,
interesting viewpoint. Weird, but interesting.

The FACT (unarguable, like a wall) is that everything else is a variable.. velocity, mo, ME, tko, bam... are dependant on velocity.

Once the bullet leaves the barrel, that's an ever decreasing variable...

that goes to zero, animal hit or not.

your point of "the better they worked" in your article is a fallocy, as the penetration decreases with velocity and SD... by your own words, the lower the SD the "better they worked"... madness.... the more radically they expanded per distance.. sure...

but if expansion is "the" answer, then why not start with a minimal SD... as you actually infer when stating that SD is irrelevant... run it at high velovity to get that "momentum" and shoot 110gr bullets in a 30-378 at 4000 fps....

by YOUR paradigm, this would "work better" as the SD would start low, and would get lower.... so it would "work better"

then again, you seem to think SD is a "pretty little card" on a bullet.

Again, sigh, take two bullets, no difference but length to change SD, and either load them at the same velocity or alter the velocity to the same momentum...

guess what?

the higher SD STILL goes deeper.

So, your original post, blasting chris (and his FACTS of penetration depths) is erroneous....

You could be a man about it, fess up, and end this with some grace...

or continue howling at the moon

jeffe

500,
Have a heart! I already work flexitime. In our business that means we start any time we like, as long as it is before sunrise and we go home any time we like, as long as it is after sunset. We have another two machines arriving from Europe in the next couple of weeks and we are negotiating for a further two from the USA. The deal is pretty much done, just waiting for assurances on the condition of the controls.

Jeffe,
The way you troll through various threads spreading irrelevant is easy to ignore. It is quite funny sometimes like your shovel comment on the fastest snake thread.

Incidentally your fretting over "worked" and "expanded" and such is just so much more

Has it occurred to you that, for an FN style bullet to expand more than another, it has to be driven substantially faster. So, same bullet at progressively faster speeds and progressively more momentum, results in similar penetration levels but substantially more wound channel volume. More work has been done. It has worked better. Despite the worse Sd. Wakey wakey, smart alec.

quote:

Originally posted by Gerard:
Jeffe,
The way you troll through various threads spreading irrelevant is easy to ignore. It is quite funny sometimes like your shovel comment on the fastest snake thread.

smart alec.

As usual, stipulation with out facts.. and, as normal, you expect persons to buy what you say, without facts..

SD is the baseline

jeffe

Jeffe,
Why don't you repeat it a couple more times to see if it may become true? I see you have no comment on your blunder with the expanded FN bullets other than vague generalisations without substance or point?

I got more rope where that came from. Care to have some of it?

.

quote:

Originally posted by Gerard:
Jeffe,
Why don't you repeat it a couple more times to see if it may become true?

Why Gerard, thank you once again for your amazing customer service advice, but i'll leave "repetition to fact" to a past master.. yourself...


those bullets shipped a month ago huh?
LMAO
jeffe

quote:

Originally posted by ALF:
Gerard: What on earth makes you think I'm bent out of shape ?

The only thing bent out of shape here is a bullet, one with too much SD

Alf! Good point!

We don't want no stinking sectional density over 0.3!

Especially with monometals it is unnecessary!

More momentum!

More twist!

That's the ticket!

Too long bullets go bananas and veer off course sometimes, aye, get bent out of shape too easily.

And thanks to BigRx for the nice anecdote.

Gerard and Jeffe,
Thanks for your use of BAM terminology. I guess I should drop the ! from the term. No longer BAM!

This was originally a tongue-in-cheek acronym for the Bullet Area Momentum product = (MV)(XSA).

Now it is the "Bullet Area Momentum" quotient = MV/XSA.


BAM of the .375 Wby with 300 grainer at 2740 fps, a modest load: 835 lbs.ft./sq.in.

This beats anything in Chris's table.

There are limits of recoil toleration and portability of gun weight involved in making a rifle a better hunting tool.

Add it all up: The .375 Weatherby is the most versatile, practical, and deadly cartridge in the world.

Gerard,

Any idea of when more .500 NE pills will be available?

quote:

Originally posted by Gerard:
We have been skirting around the deformed bullet shape. The long and the short of it is that a mushroom shape is less effective at causing trauma within the wound channel than a cylinder shape. This means that a caliber size cylinder at similar speed to a same calibre bullet, that mushroomed to 1.5x diameter, will produce the same size hole at handgun velocities. As speed increases, this effect is enhanced to the point where the temporary wound channel will contribute much more volume to the permanent (crush) cavity than the crush cavity itself. See the pictures of the springbuck with 1.25" hole made by a .224" cylinder.

Indeed Gerald, the cylinder shape is probably the best to induce trauma for any given caliber as it tends to radially displace this animal resistance I have coined "RTD". Any change in coefficient of form (rounding of corners on frontal area) allows more displaced "resistence" to get behind and away from the compressive forces that are induced. I even believe the full caliber shoulder on a semi-wadcutter shape tends to act like a full caliber square cylinder hydraulically if this shoulder can keep its square edge.

But I believe there is even a better shape! Your three bullets in the attached article that caused debate between "worked" and "expanded".
Those fired bullets display some of what I speak. I will call the expanded shape the inverted "truncated cone".

I have duplicated this terminal shape (in wet packs) with .22 rimfire by modifying them with a flat point. Small game testify to its effectiveness! A hollow point may expand to a larger frontal area but with rounded corners and even loss of integrity. I experimented with a small drilled hole (hollow point) into the already flattened .22 only .045" diameter. This allowed me to reach a .44 caliber upsidedown "truncated cone" shape with the square front still intact and flat and becoming the best of small game bullets.

I have thought the cup point in a flat point monolithic may one day take the place of softs on DG. My experimentation have shown broader and shallower cups or cavities seem to allow the metal to "roll back and around" creating the lesser coefficients of form as to trauma.

So if ways of manufacturing that allow the monolithic to expand while holding this flat front, this upside down truncated cone, at DG velocities, whether it be by a small hole as stated to weaken and initiate displacement, or by tensile strength change by material or annealing? (Too soft may defeat our purpose however.) Who knows, one may end up with not having softs and solids both in the box at once when eye to eye with Mr. Buff.

I appologize for keeping Gerald from your bullets 500Grains.

BigRx