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You can only lead a horse to water. I guess you can shove his nose in the water. You can whip him. You can yell at him. In the end, he'll only drink if he chooses to drink. If he has made his living telling others water does not exist, he likely won't drink--or at least not in public. It's junior high math, Gerard. Really. | |||
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Now that's a wee-wee way of answering somebody's questions! Not that I can either, but I wonder who is now mathematically challenged? | |||
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 Its tough when you think you have all the answers. I have been at this for 30 years and I still marvel at how stupid I am. Game King, Are you going to test all the bullets at 2300fps? | |||
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Form is indeed important as it affects the drag encountered in air: * Let us start with a cylinder FN or Wadcutter bullet. * Then we turn the RN bullet into a Semi-Spitzer. * Then we turn the Semi-Spitzer bullet into a Spitzer. * Then we turn the Spitzer bullet into a Spitzer Boat Tail. * Then we turn the Spitzer BT bullet into a VLD bullet, such as a Berger match bullet. In fact, when we do not cut a crimping groove into a bullet, we can reduce the drag further. The above form parameters are design items that we add to a given bullet with a given SD - assuming a .308/150 gr bullet. Application will then determine which ones we pick, be it for: * Hunting at short-range * Hunting at medium-range * Hunting at long-range * Target shooting at short-range * Target shooting at medium-range * Target shooting at long-range So, SD is the base that we start with, and then we improve the form factor (i) to suit our intended purpose/application, be it to hunt or for target shooting at the various ranges as detailed above. The inter play of SD and (i) is always there - we cannot wish it away. The fact that a 200 gr RN bullet may have a lower BC than a 180 Spitzer BT bullet does not invalidate the inter-play relationship between SD and Form Factor. SD will generally improve the BC, provided that one does apply "destructive forces" to cancel the benefits that increased SD is bringing to the table. Thus the form factor can be used in a destructive way, just as it could be used to reduce drag. Warrior | |||
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Chris/Truvelloshooter/Warrior In your example all the bullets are 150gr .30 caliber bullets. When you walk into the shop to buy bullets, do you say to the guy behind the counter "May I have a box of thirty caliber, point two two six sectional density, (Insert Brand Name) bullets please?" In any of the gun shops I have been in, you will be met with a blank stare. Once you have explained what you want and leave with the 150gr bullets, he will probably phone his friends to tell them about the wierdo who just visited his shop. Sd is the relationship between mass and caliber. The caliber of your 308 Win cannot change so it is much simpler to just ask for bullets by weight. When you use your ballistics program to calculate drop and wind drift tables, where do you input the Sd? I own several pieces of ballistics and design related software and not a single one asks me for the Sd. Sd cannot walk on its own. It always needs a crutch and the crutch is always of more use than Sd. Now there is a novel idea. I have a feeling I am going to learn something. Dunno what yet but it is going to be something.  | |||
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I will change the velocity if we all can agree on one. What I am trying to do is provide a test that is simular to hunting conditions. The bullets need to open in order for each of us to be happy. I believe in SD but if I test a 1200 Feet/second what good is that to the hunter. If I test a 4,000 FPS what good is that to the hunter. I am not a richie rich with 50 guns in african game room. I chose those calibers because I have them. I am looking for an impact velocity that would be normal for those calibers. I don't have a 458 rem. I don't have a 204. | |||
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If SD is indeed coincidental or totally irrelevant, then I suppose it should be so in all spheres of ballistics - internal ballistics, external ballistics and terminal ballistics - and not just so in some cases. I find it strange that all the mathematicians/ballisticians are clinging to it when they do ballistic calculations and extrapolations. When a particular parameter is a ratio, it cannot constitute a fudge factor when in fact its base elements are valid entities. In fact ratios have as its purpose to be handy, to be informative or to instruct. A fudge factor for me is a correction factor quite separate and stands on it own to amend the answer to a position that is more correct. The word "fudge" has a very bad connotation and cannot be ascribed to SD. IF so then we must be consistent and level the same criticism against the ratio of Mo/Xsa, which we know is in fact very handy in terms of giving clues as far as penetration (terminal sphere) is concerned. In flight (external ballistic sphere) we only have to contend with air drag with fewer imponderables than flesh, bone, angle of attack, fragmentation and expansion of diameter. Those that linked SD to BC certainly felt that it was very handy. Warrior | |||
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Game King Unless someone else has a better idea, 2300fps should be good for the bullets you mention. It will be interesting to see the results and thanks in advance. It is a lot of work to set up such a test and, unless you have done it yourself, one does not realise how much time it can take. Alf, Regarding the false statements below: "High Sd bullets penetrate better than low Sd bullets." "High Sd bullets have better BCs than low Sd bullets." "High Sd bullets give better weight retention than low Sd bullets." "High Sd bullets are better in wind than low Sd bullets." "High Sd bullets kill better than low Sd bullets." and your comment: "In this you are absolutely correct ! and I agree one hundred percent." is all I have been saying all along. Check the comments I have made on Sd. I have only taken issue when one of the above falsehoods were mentioned. Quite frankly, I do not care if Sd is buried in some equation somewhere in the software I use. I have only ever needed to work with the elements of Sd and, for the mathematically challenged used car salesmen like me, it makes for a clearer understanding of a complicated subject. Warrior Chris, See my reply to Alf, above. Jon A, I notice your test of Accubond bullets. .308 200gr Sd .301 penetration 11" 3170fps mv .338 225gr Sd .281 penetration 12" 3100fps mv .375 260gr Sd .264 penetration 12" 2700fps mv The results are quite logical but how would you connect Sd to what you observed. You can do it with math if you want to, I will try to follow.  | |||
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Well said.  Warrior | |||
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Gerard, I really did not think the above statement would have puzzled you, but apparently it has. It simply means that the BC of a bullet can be lowered by virtue of changing the Form Factor so as to increase the bullet's drag. That is the "destructive way". For more clarity ... this is practical example: Pick a bullet with a huge flat meplat (as big as possible) instead of a sleek Spitzer BT bullet for participating in a 1000 meter match. Likewise if one normally uses a Woodleigh RN bullet for close range hunting, one can opt for a Spitzer type bullet for long-range hunting, like one of your HV bullets. This way we use the form factor to improve the BC. The form factor thus become a bullet design parameter inline with the bullets intended purpose - in other words it is the choice of the bullet maker, whereas SD is governed by the mass and diameter. And that means in my example of all the bullets weighing 150 grains, that SD is fixed. I did it specifically that way for clarity to illustrate how we can manupilate the form factor to move the BC up and down. Incidentally, is there any program that ask you to input Mo/Xsa?  Enough said. Warrior | |||
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Just give one example of one individual, namely from Dr G. Kolbe - page 103: "Ballistic tests to determine the Drag Coefficient over a range of velocities in which one might be interested is a time consuming and very expensive business. It is just not practical to perform these tests for every projectile shape or variation of shape. It is much more convenient to have good ballistic data on a few standard projectiles and introduce a "Form Factor", i, which represents the shape of the projectile of interest. The form factor can then be determined with relatively little experimental effort, which then allows the use of a Drag Coefficients for a standard projectile appropriately scaled by the Form Factor to represent the projectile of interest. this is a valid approach so long as the test projectile has a shape not too dissimilar to that of the standard projectile to which it is being compared. For a projectile having the same shape as the standard projectile, i=1. Projectile having different shape, mass and diameter can then be compared to a standard projectile of unit mass and diameter and having the standard shape. It is very convenient to introduce the Ballistic Coefficient C= SD/i " We should be aware of the fact that a form factor requires accurate air drag or C.D. measurements for the bullet, and also a standard reference projectile of the same shape. Here are some drag models commonly used in small arms ballistics: G1.1 - Standard model, Flat Based with 2 caliber (blunt) nose ogive G5.1 - For Moderate (low base) Boat Tails - 7° 30' Tail Taper with 6.19 caliber tangent nose ogive G6.1 - For flat based "Spire Point" type bullets - 6.09 caliber secant nose ogive G7.1 - For "VLD" type Boat Tails - long 7° 30' Tail Taper with 10 caliber tangent nose ogive GS - For round ball - Based on measured 9/16" spherical projectiles RA4 - For 22 Long Rifle, identical to G1 below 1400 fps GL - Traditional model used for blunt nosed exposed lead bullets, identical to G1 below 1400 fps GI - Converted from the original Ingalls tables Warrior | |||
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I would like to perform this test as accurately as possible. Anyone who sees flaws in my method please speak up. This will make the tests more valueable. I think we all can agree that Energy, bullet form, and bullet constriction effect penetration. What we don't agree on is should Sectional Density be added to the list above. What I am trying to determine is does the SD of a hunting bullet signifagently effect penetration. E=M*V*V If the Mass of two bullets and the velocity of two bullets are equal at the point of impact then Energy must be equal regardless of shape or SD. If two bullets are made of the exact same material and only a single material is used then the constriction must the same. (This makes the barns X bullet the best choice for the test.) I will have to measure the meplat, ogive and tail charaistics to determine whether or not the two bullets have the same form. SD=M/Diameter I have chosen bullets of the same mass so the only variable that can be used to alter SD is diameter This means that by using two different calibres then the Secetional Density of each will differ and all other variables will be the same. This leads to my test perameters I would like to fire a set of five bullets each .284 150gr Barnes X bullet and .308 150gr Barnes X bullet To achieve equal velocities at point of impact, rather than working up load after load for each caliber, I will use a cronograph to find the distance at which the velocity is 2300 Feet per seconed. What this means is that the distance to the point of impact for the two calaber sets of bullets will be different. I do not believe that this has any impact one the test. Once the distance is determined I will fire five bullets of that calibre. one each into a seperate test media container with the cronograph sitting just in front of the container. I will then switch over to the next calaber and repeat this process. data from each shot will be recorded an posted. Together we can decide whether or not differences in penetration for the two calibers are signifigant or nomonal. If this goes well then I will try the accubond and round nose bullets. The problem here is we really have no way to determine that different calibers of the same brand of bullet are constricted exactly the same. Does anyone see any flaws in this proceedure? | |||
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I am only repeating this as you stated that this was a "novel idea" to you. I don't think so, as Krupps knew this already in 1881 !!! | |||
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Alf, Could you tell us in a nutshell what the basic points are that are being made by Douglas Lindsey? Thanks Warrior | |||
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Why are some of us still struggling with SD? Being challenged in some or other way? Read the next posts for more clarity on the subject:
OWLS My Africa, with which I will never be able to live without! | |||
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Energy cannot stand on its own legs. Momentum cannot stand on its own legs. Mass cannot stand on its own legs, Velocity cannot stand on its own legs. Diameter cannot stand on its own legs. SD cannot stand on its own legs. Now what now ? .... I think I mentioned this many a time. No matter how hard we try to deny the contributing role of SD in the greater whole, it won't go away, as the damn ratio is there whether we like it or not, but more importantly, SD is hurting no one - it just deals with desity in a given bore size and volumes will differ when we play around with materials of different specific gravities, thus it is clear to see what role it will play in a pressure vessel (chamber). Warrior Warrior | |||
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Gerard, your logic is as poor as your math. Proof that one factor is not the only factor that determines an end result IS NOT proof that it's not a factor at all. That you can stare directly at a simple equation that is not in dispute by anybody and claim it doesn't say what it says is why I quickly lose interest in these "debates." It's simply absurd. One last bone, the RN's BC goes down with increases in velocity because bullets shaped like that most closely follow the GL curve. The GL curve has Cd increasing with velocity while most other curves (including the G1, G5, G7, etc, have the Cd getting smaller with increased velocity. So when you give a bullet that flies close to the GL curve a BC in terms of the G1 curve, its G1 BC will get smaller with higher velocity. | |||
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Game King, You will find that Mo/Xsa will yield the highest correlation coefficient, as it recognises the dynamics of in-target drag. As I have pointed out previously, with examples, SD can never be used as an absolute measure and not accross different calibers. But let us see how your figures pop and then let us do the Mo/Xsa calculation for each group. Good luck with your attempt ... curiosity kills the cat. Barnes-X bullets will be your best bet due to very uniform expansion and 100% retention of bullet mass, ensuring momentum levels would stay essentially the same. Warrior | |||
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Jagter: Why the vehement defence of a specific product like GSC bullets when clearly this debate is about a principle and nothing to do with the merits of a specific bullet or product? The principle is the position that; the ratio of a projectiles mass to it's reference area plays a central role in the drag the projectile is subjected to when acellerating out of the barrel, when in flight and finally when it penetrates the target; no more no less! In flight we see a specific and defined relationship between a projectile's BC, it's SD and form factor for a specific drag functionas pointed out by JonA. It is undisputed in the world of ballistics science. The relationship is direct and stands in a one to one relationship, not coincidental, but also not isolated ( always in context of drag) This relationship forms the very basis for the calculations used in decribing the bullet's flight time. It was used historically ever since artillary officers tried to calculate how to elevate their guns to get distance on their shots and is incorperated in the most modern 6-DOF programs used in modern ballisitics. And though Gerard shrugged off my question on exactly how he derives the BC values of his bullets i'm sure that if he looks at his calculations and or computer programs SD is locked up in all of them  Now there is this experiment by one "Game king" and I have to wonder if he / she is not simply a troll planted to humour us in this matter?????? a Sudden "new member" only 11 posts to his credit Makes one wonder??Well to humour his "experiment" I can but shoot it down based on the fact that it violates the "rules" of the scientific method as it cannot isolate SD as an enitity in the penetration proccess and thus any derivation made will be invalid as far as the value of SD goes. The reason: In order to isolate SD alone in terms of the penetration proccess he would have to have a non deforming, non fragmenting, non yawing ( more correctly zero angle of attack) projectile ( looking closely at this statment it actually implies a lot of things to standardise) , and in this instance we clearly have not. Gerard shoots down the contribution of SD, stating that by somehow inferring something magic in his bullets they "perform" better than conventional bullets? Do they really or are they simply and endorsement of the harnassing of the value of this very concept of SD ? Nothing more than an illustration of how SD operates in target and how it can be manipulated to work "better" in target ? Then this whole issue of bullet performance and incpacitation times of animals. A difficult if not impossible to define parallel. Sadly we have two entities, the one projectile behaviour and the other living animal bahaviour to trauma and physical insult. Bringing the two together in a scientific way to draw meaningful conclusions again in a scientific way is the problem. Too many variables to come to universal conclusions and to make universal "rules" Warrior: Sorry no magic relevation by the editor of Journal of trauma, however very importantly an acknowledgement that the time has come to weed out the junk science and half truths that has been perpetuated regarding ballistics science in the literature and a de facto endorsement of Fackler and other's all over the world call to this effect. | |||
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Why? Far better bullet design, construction and ability to make use of high velocities enhanced by true drive band principle, shifts the SD thing right into the background where it belongs. Nothing to worry about! OWLS My Africa, with which I will never be able to live without! | |||
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Gerard, April Fool's day is coming up soon. That would be a great time to announce that you are giving up this schtick, this comedy schtick you have going about sectional density being unimportant. The square bullet SD is funny enough by itself, without you trying to make it nonproportional to reality. A passing chuckle about square bullets with imaginary pounds per square inch, that are proportional to real pounds per square inch will do just fine. Enough of yanking our sectional density chains already!  | |||
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Game King, You would be better off to use the same type of bullet with the very same construction, like say all Barnes-X or TSX bullets. You are about to do cross caliber comparisons, but at least you attempt to keep the velocity and momentum values the same. However, increased SD has its main value within a given caliber and it was never meant to be for making cross caliber comparisons, because SD is just a ratio, and we do not know the velocity applied & the momentum value that goes with it - i.e. higher or lower. It would be plain silly to argue that a .510/535 gr bullet with an SD of .294 is mediocre and a .338/250 gr bullet with an SD of .313 is better. This is skewed reasoning, as depth of penetration is not always the only criteria. Velocities can be very different, and so momentum will be different. Comparing bullets of different construction and hope the higher SD of a frangible bullet would miraculously bail one out would be plain ludicrous. So yes, common sense must prevail. We also know that there is also a limit to increasing SD (bullet becoming longer) as it is governed by twist rates. There is also a trade off ito magazine length and how much powder erosion one is willing to accept. Each caliber, based on its twist rate, length of free bore and magazine size have a band in which bullet length can vary - too short is no good (bullet should have enough purchase on the case neck) and too long (leading to loss in velocity) is also no good and that brings us to the concept of the ideal bullet length for a given set-up to achieve ballistic balance. However, my tests with .284" Barnes-X bullets in my 7x57 mm proved to me the value of SD within a given caliber - it correlated directly with Mo/Xsa values within the velocity band that I conducted my tests. I shot bullets into a wetpack made from newspapers at 25 yards. The results were: 175 gr @ 2,390 fps --- 63 cm of penetration (24.8 inches) 142 gr @ 2,490 fps --- 53 cm of penetration (20.9 inches) 108 gr @ 2,610 fps --- 42.5 cm of penetration (16.7 inches) Barnes-X bullets start to lose their petals from around 2,650 fps depending on caliber, which makes it one of the strongest bullets out there. I prefer a bullet to go though the vitals with it petals fully expanded and not to lose them within the first inch or two. This refers mainly to construction as hunting bullets very seldom have striking velocities in excess of 2,650 fps save for those ultra velocity cartridges. The 175 gr Barnes-X bullet is rather long, and when I am through with my supply that I bought below cost when PMP dumped all their X-bullets, I will get the 160 grain TSX version to play around with. It should give me around 2,435 fps, which is quite adequate out to 200 yds for the type of hunting I do. For the same reason I like the 160 gr Rhino Solid Shank Bullet better than the 170 grainer. Here is the explanation why a 375 H&H will out penetrate a 458 Win.: Cartridge --- Mass---- Velocity ------ Mo ------ Xsa -- Mo/Xsa .375 H&H -- 300 gr -- 2,530 fps -- 108.43 -- .141 -- 771 .458 Win --- 500 gr -- 1,900 fps -- 135.71 -- .210 -- 647 Take note that the .458 bullet has both more momentum and a higher SD than the .375 bullet, but when the other variable (Xsa) comes into play, it changes the outcome. Warrior | |||
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Game King, Curious to know how you test is coming on bud. Warrior | |||
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Jon A, Chris, You miss my point regarding Sd entirely. Look at the statements below. I regard these as false and misleading. Is there any one of these statements that you regard as true? No qualification of this addition or that explanation - do they hold water as stand alone statements under all conditions? "High Sd bullets penetrate better than low Sd bullets." "High Sd bullets have better BCs than low Sd bullets." "High Sd bullets give better weight retention than low Sd bullets." "High Sd bullets are better in wind than low Sd bullets." "High Sd bullets kill better than low Sd bullets." | |||
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Of course these cannot hold water while standing alone, sort of like a case of Castle in the town drunk:
Still yanking our sectional density chains, eh Gerard? | |||
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The only one to ever make those statements "as stand alone statements under all conditions" has been you. The Strawman you have built, who makes these statements so you can knock him down. Unfortunately for you, "proving" those statements that you invented (because you could not do it to the statements we have really made) incorrect in no way proves SD is not A FACTOR in all those events. Nor does it make you look anything but silly. Boooorrrriiiinnnggggg. | |||
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 Jon, your expectations of Gerard are a little unrealistic. He's neither scientist, mathematician, nor ballistician. He's a salesman. ----------------------------------------------- "Serious rifles have two barrels, everything else just burns gunpowder." | |||
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Hey Gerard, All those statements are "True" for the Hunting Grade Bullets I use, and have used. Why do you believe those statements are False? | |||
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Now guys, be nice. Gerard makes the best bullets possible. This sectional density thing is a comedy schtick that he has gotten a lot of mileage out of. However, it is April Fool's day now, where he is, and time for him to admit the joke. He has missed the cue for several years now. Time to fess up Gerard. Let's all have a good laugh now. Applause for a brilliant charade.  | |||
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Jon A, Oh man, that is rich. I suppose you have begun to realise that you do not know everything and the increasingly insulting style is your way of hoping the discussion will go away. There are several things you overlook in your idolatory of Sd. Bullet design does not revolve around Sectional Density and the reality of existing cartridge designs dictate many compromises that you do not consider. While you think you know everything, you will have difficulty accepting the fact that you overlook things. As (if) you mature, you will see what I mean. In the meantime, try to keep an open mind and be less condescending of those who do not know everything. You can learn much from them if you will look for the cues and this will make you more knowledgable. 400 Nitro Express, I must apologise. I did not realise that you will take correction so badly. By the same token, I had to point out how wrong you are about drive band bullets. It was the proverbial rock and a hard place for me. But if that makes me a "salesman" and, in your opinion, unable to grasp the principles involved in making good bullets, I have to question your ability to reason clearly. GSC drive band bullets remain unique in what they offer and in how they work. It is a pity you are not prepared to find out more about them. RIP, I realise full well how Sd fits into the scheme of things. The problem I encounter several times a week (for the last 10 years) is the layman who has heard about Sd and comes up with one or more of those false statements. If we educate the beginner along the correct lines such as bullet quality, stability and the factors that will enable good shot placement, we will do more good than by telling them they need high Sd and then leaving them out to dry. To all, What are the negative aspects of high Sd? Are there any? | |||
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Gerard, I get it. Let us continue the public service campaign then, by all means: http://www.gsgroup.co.za/articlesd.html One negative aspect of too high SD: Long bullets in the monometals are more apt to tumble in the traditional twist rates designed for stubby lead-cored bullets. There is a move afoot to do away with all lead in sporting ammo, even rifle bullets, even military weapons world wide, in favor of environmentally friendly lead-free bullets. I don't know how the depleted uranium fits in here. The masses had best get used to lower SD numbers, and the better bullets that bring them. How am I doing? | |||
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Another negative of higher Sd is that it adds to the destruction of the bullet, as does higher impact speeds. So whether you increase the speed or increase the weight of the bullet, either way you add to the probability of the bullet breaking on impact. | |||
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And Duncan MacPherson in _Bullet Penetration _ would back that up. SD drives expansion, but only when coupled with velocity. Velocity drives expansion but only when coupled with a mass that has a cross-section to be expanded. Yes Gerard, yours is the better way to look at it. I personally think the artificial definition of SD should be refined: SD's beyond 0.320 are not to be spoken of. They are only allowed to be stated as "plus 0.320" and then only with the rolling of eyes:  Any serious work should be broken down purely into mass, velocity, and XSA, before getting into the fudge factors. It is actualy what is done anyway. | |||
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500 NE ---- .510 Bore --- 570 gr bullet --- SD = .313 .458 Lott -- .458 Bore --- 480 gr bullet --- SD = .327 .416 Rigby .416 Bore --- 370 gr bullet --- SD = .305 .375 H&H - .375 Bore --- 300 gr bullet --- SD = .305 9,3 x 62 --- .366 Bore --- 286 gr bullet --- SD = .305 If these load combinations can't do it we could pretty much give it up !!! Warrior | |||
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AlF, I am a real person. My name is George Saloom. I live in Champion, PA. If you are truly concerned as to wether someone is playing tricks on you then call information, find out my telephone number and give me a call. As for my so called "EXPERIMENT" there is A little known concept called inferential statistics. Perhaps you have heard of it. It is taught in college. That is where go after highschool. For this specific so called "EXPERIMENT" If I shoot about 200 rounds of each bullet that I wish to test I will be able to determine if there is a signaficant difference between the penetration of the two bullets. "Why 200 rounds?", you ask. That allows me to be cofident that if I repeate the experiment multiple times I will get the same results in 95% of those so called "EXPIRMENTS". That is how some guys prove or disprove Ideas. As a new member, I am disheartened by those who just want to "yack yack yack" and lack of intrest in finding out the truth. I am not on this forum to "yack". I thought I could learn something from the so called "EXPERTS" on this forum. | |||
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Game King, Your proposed experiment as described on 23 March will be very interesting. Especially the variety of mono and conventional bullets. You must padon us if we suffer from a bit of paranoia at times. It often happens that a troll creeps into a thread and causes disruption. When members are guarded about their real identity, no name, url, e-mail or other signal that a real person exists on their public profile, some suspicion creeps in. Keep us posted on your progress, I, for one, would like to see what you find. | |||
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Warrior, I never pretend to be an expert I am just learning. I hope I continue to learn until my last day on earth. Would you give me a one or two sentence definition of Xsa. I don't quite follow why SD cannot be used from on caliber to the next. If velocity, weight and form remain the same then I would expect a smaller caliber bullet to penetrate more. I do realize that at some point a high SD becomes a liability. A very skinny & very long projectile is more apt to bend and deflect as it passes from air into a more dense media. This would not be a conventional bullet. It would be more like a lead or copper spear. In addition if construction is ignored and a high SD is considerd in our bullet selection we also miss our objective. If a bullet achieves no expansion in the media then what good is that? For me the only way to seperate SD from mass is to change the caliber. Is my logic incorrect? When the mass, velocity and form of two bullets are simular, SD becomes important to me as a tool in determining which caliber to choose. ie (.277 vs .308 or .338 vs .375) In other words SD helps me decide wether to use a 175 gr 7mm or a 180gr .338. This would be a real world decision on which rifle and bullet weight to use. | |||
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Ok guys, Now I have thirteen posts. I have not started to expirement yet. It will most likely be June until there are results to post. Please be patient with me. I am trying to put this together in a proper manner. This is to insure that I really acomplished something besides have fun reloading and shooting. Thanks. | |||
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