The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Rifles Big Bores Who's correct regarding penetration of softs? Art Alpin or Pierre van der WaltGo | New | Find | Notify | Tools | Reply | |
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On page 123 of "Any Shot You Want", Alphin offers the suggestion that "Conservation of angular momentum is key in the performance of a soft point bullet. If the petals expand too far, it will reduce the rotational velocity and the bullet follows a wildly erratic path in the animal." The Dead Tough soft point is/was designed to expand slightly at the nose, leaving, as described on page 125, an "undisturbed rear portion of the bullet, containing the majority of the weight, (and) acts the same as a flywheel on an engine. It tends to conserve angular momentum, thereby keeping the pullet spinning and penetrating on a straight path through the animal". On the other hand, on page 77 in "African Dangerous Game Cartridges", Pierre van der Walt writes that, "The more one examines the matter, the more obvious it becomes that low terminal sectional density (considerable expansion and shortening) is essential to achieve terminal stability. The proviso is that the change in sectional density must primarily stem from expansion and not weight loss...". Who is right? | ||
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Pierre is right. You need the weight at the front or it fishtails. | |||
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Both writers are noting features of the bullet that will minimize the directional change. Just as a gyroscope will keep vertical when subjected to side forces, a bullet with sufficient rotation will keep point forward and given sufficient mass will continue straight. I don't see the length, referred to as sectional density as having significant impact- it's a matter of bullet mass, frontal area, it's shape and it's angular momentum. | |||
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So is a faster than normal twist rate (my 500 Jeffery has a 1 in 10" twist barrel) a factor? Regards, Chuck "There's a saying in prize fighting, everyone's got a plan until they get hit" Michael Douglas "The Ghost And The Darkness" | |||
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Pierre van der Walt....He has more "field experience" using all the bullets, and better contacts with the pro hunters.. Art A made some good bullets but his Lion Load was a bloody joke unless you could slip one between the ribs of a Lion behind the shoulder. Art was too much into technical aspect of bullet performance..The true test of any bullet is a couple of hundred head of game.. I have read and reread both of their books, I had more than a few issues with Arts ideas, in that they didn't jibe with mine, but never had one issue with Pierre van der Walts book, its totally consuming and probably the best and most informative book I've ever read on the subject, and the all time best reloading manual out there in that he pretty well quoted every load for ever caliber, what book it came out of, barrel length, everything. Its a must for every African hunter, newbie, expert, or otherwise. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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Chuck375, Depends on who you talk to, those that are et up with tech will say yes, the animal shot won't know one way or the other!! Its apparent that the faster a bullet turns the more it will expand is basic, but will it stay together, will it do sugnificantly more damage it won't penetrate as well, but how close with it come to the same penetration and on and on. The subject is so complicated only geeks can explain it in a cloud of vocabulary.  I see the explanation as if you can't prove it, then baffle"em with BS... Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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Bullets can't be spun hard enough to stay stable in tissue. | |||
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When I was at a benefit/picnic in Seely Lake Montana about four plus decades ago, the big attraction was "shoot the Buick" for a dollar. There was a 55 Buick on blocks in the field. A fella there had a pre-65 M70 in 375 H&H. I'd never seen a gun that big. He told me it was his deer gun and let me shoot it at the Buick. I asked why he was shooting such a huge caliber for deer. He told me his Dad had given it to him, it was his only rifle and "they don't get up". Seems about right to me  Regards, Chuck "There's a saying in prize fighting, everyone's got a plan until they get hit" Michael Douglas "The Ghost And The Darkness" | |||
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Regards, Chuck "There's a saying in prize fighting, everyone's got a plan until they get hit" Michael Douglas "The Ghost And The Darkness" | |||
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That is right. So Art is out to lunch and Pierre more right on the terminal ballstics here. Fast twist does aid in the transition from air into the animal, by stabilizing bullet for a straight-on entrance, but once inside the denser medium, twist does not provide gyroscopic stability of the bullet. In the denser medium the penetration then depends on shoulder stabilization from nose shape (flat nose advantage), as well as dart stabilization/shuttlecock effect from the forward center of gravity provided by nose expansion. Those two factors work to keep the momentum vector on course, as it works against the resistance of target medium/game animal tissues. But if the bullet is too long, it is harder to stabilize by those mechanisms. If it is too short, it lacks the momentum over frontal area ratio needed for success. Momentum drives bullet penetration as well as bullet expansion. Nose expansion is driven by sectional density (SD) of the bullet at impact. The greater the SD of an expanding bullet, the greater the expansion at any given velocity. Momentum (MV) requires velocity as well as mass. Of course higher velocity increases expansion and also increases resistance of the "reactive" medium to penetration. So nose expansion really puts the brakes on penetration, like a drag chute, due to increased resistance, due to frontal area of the bullet as well as increased drag from the impact-velocity-reactive medium being penetrated. My head hurts everytime I start thinking about the penetration of expanding, frangible, or "expangible" bullets in game animals. But Art is wrong on the "flywheel" driving penetration, this much I know. Just use a well constructed soft of moderate velocity and SD of about .3 for conventional cup and core bullets, and heavier and slower works with them too. Lighter bullets and faster velocities with monometal "expangibles" have proven themselves also. Depend on FN solids if you want two holes in the game animal from any angle. Riflecrank Internationale Permanente. Incurable is spelled the same in French and English.  | |||
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I think will take anything Alpin says with a veryt large dose of salt! | |||
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That does seem to be the case with a lot of "Any Shot You Want". While it does contain a great amount of useful, pertinent, and accurate information, too much of it reads like an infomercial. In my recent rereading, I could not help but see Alphin's footprints walking on the articles attributed to Craig Boddington an Finn Aagaard. (Can't say I noticed anything unusual in Weilands contributions...) A concurrent reading of Pierre van der Walt was striking and got me to wondering. | |||
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The science of penetration mechanics is correct ! Those who adhere to the science have the answer ! So in that spirit I would suggest as a departure point the book Wound Ballistics by Beat Knuebeuhl. 2nd edition. ( The first was by the late Dr Carl Sellier and Knuebeuhl This is a scientific work. Further reading would include Knuebeuhl's book title "Geschoss" which sadly is only in German. Coates and Beyer as published by the US Surgeon General is old school and very important as a historical text so is The Scientific basis of Trauma a British publication ( now out of print) in which the wound ballistics section is in keeping with the modern post 80's view of terminal ballistics. | |||
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In the tech world one can get a big time headache reading and listening to such blather.. The bottom line is still a soft on top followed by solids for buffalo, Hippo,....softs for Lion, Leopard and all but elephant, where only solids has been my choice, and its worked. This pretty well works for the .338 Win/9.3x62 on the bottom, to the big 50 double rifles..If I had to pick one I would pick a 375 or 40 cal. as minimum to a big 50 with solids. and get the job done..Its just not that complicated if one can shoot. I feel confident enough with a 375 with solids, but not with softs btw, going up from there..Mostly I feel that first and foremost a bullet must get into the good stuff so penetration is most important, not that expansion isn't, just if I HAVE to make a choice do I feel such. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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This is the most concise explanation I have yet read. Spoken like a true master. Thank you, and I am going to pirate it; unless you ask me not to. | |||
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This argument is nothing more than "which kills, expansion or penetration"...couched in quasi-scientific smoke...and all the ifs, ands or buts that go along with it. Angular momentum must be conserved no matter HOW...angular momentum's energy is transferred at right angles to the direction of the axis of the bullet, i.e., down the barrel toward the beasty...the SAME WAY a crankshaft transfers up and down energy of burning chemical energy through pistons and changes it into rotational energy at the flywheel and down the power train...the flywheel conserves the rotational energy and releases it at a slower, evener rate or a crankshaft attached to a propeller pulls an airplane through the air or a bullet transfers energy to disrupt(expand) a soft bullet and disrupt the animals CNS or punch right through it to whack another beasty standing behind the first or out across the plans. Most thoughts I've read on forums on this "which is better" subject are just TOO simplistic for the actual instantaneous action of a bullet killing an animal. For all intents and purposes it a combination of velocity, bullet mass, angular momentum, and bullet construction and all the other variables that go into the equation that conveniently get left out or nit picked like personal bias/favoritism, weather, entry angle, the animals mood, size, sex, caliber, ad infinitum, ad nausium....that does the job...NOT just one or two things. It's always easy to badmouth and disagree with some and pat others on the fanny...but how many hang their backsides out and write a book and take the chance of becoming targets...NOT VERY MANY...and how many just don't understand the jargon that goes with geek speak...just saying, think about it.  Luck   | |||
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And no matter what the theory says, once a bullet hits anything, no one know what it will do. We can argue about the theory until the proverbial cows come home. I have seen enough bullets defy all preconceived idea enough times to just rely on practical experience rather than theory. I have seen the same bullet whiz through an animal from one end to another. And I have seen the same bullet change direction 90 degrees in another. I have seen this happen with both mono metal hollow points and round nose solids. | |||
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On that issue, A Marine in our unit fired his M16 into an attacker that was charging him. One of the bullets entered and exited the chest and almost hit the Marine. That was when 55 gr 5.56 bullets were fired from 1-14" twist barrels. Some of "the experts" said the insufficient spin caused the bullet to tumble and resulted in the 180 degree turn. I figured the bullet caught the inside of a rib & lacking the ballistics to punch through, just rode the inside of the rib around to where the rib ended, thus coming out the front. The military wasn't into autopsies so how the bullet changed directions was never answered with any evidence, but it was clear, when a bullet hits something, particularly light long bullets, all bets are off. | |||
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LHeym500, I would be honored to be quoted on that, as long as you don't give anyone a headache. Stop quoting if anyone starts rubbing their temples. Riflecrank Internationale Permanente Incurable  The 404 Jeffery in Nebraska, 2004, Ray Atkinson Booking Agent, Shooting the Moon and Bison:   | |||
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Now I have to get a copy of Pierre van der Walt's book. Thanks for the tip. While Art Alphin's story that he started A-Square and developed "his" .500 (.510 Weatherby) after having an incident with a cape buffalo sounds awfully similar to Jack Lott's story of the origin of the .458 Lott, and anyone who claimed that Peter Capstick was every bit the PH he claimed to be and deserved a round named after him could be suspect... If Peter Capstick can be said to have at least revived interest in African safaris in the 1980s and 1990s despite the probable stretching of the truth here and there, then Art Alphin can also be said to have kept the big Nitro Express cartridges alive when the industry stalled and Kynoch stopped producing ammo in the early 1970s. That said, Alphin had an absolute passion for powder compression that I've never seen anywhere else, and in my opinion, all A-Square ammo is suspect for powder clumping and erratic ignition/velocity, including the ~170 rounds that came with my .500. I ended up having to pull the bullets and pry out all the solidified/caked powder and start over, but that's another story. Luckily it didn't involve a cape buffalo.  | |||
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Jlabreck, Van der Walt hit a home run with his book. I highly recommend it. Gotta echo LHyem500's sentiments too, thanks for the excellent summary RIP! What you wrote is pretty much in line with what van der Walt writes. Also, thanks for the title suggestions Alf. I was hoping you'd be willing to give food for thought! | |||
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I just want it to be known, I don't pat anybodies fanny just because I agree with them! | |||
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There's few things I'd agree with Art over anyone -- and the authority these days is Michael McCurry opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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You can also buy Pierre's book as an e-book, I have both. The e-book load tables can be a bit hard to read. Love how he describes some British cartridges as "The Englishman"! Think that was the 375H&H. DRSS | |||
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With all the above being discussed: Question; Explain the sterling performance of the traditional Nosler Partition. It loses it's forward weight bias very early in the game, yet almost always penetrates straight and through. Is it now transformed to the "flat Point solid" in it's flight characteristics? Just really interested in those that know the science. I understand as Saeed did, "thing's happen." As I have written before; Elmers 275 Speer in the 338 WM was the closest thing to a magic bullet I have ever seen. Heavy, long and a simple cup & core. Never failed, close or far. Two holes always. Dead always. "The liberty enjoyed by the people of these states of worshiping Almighty God agreeably to their conscience, is not only among the choicest of their blessings, but also of their rights." ~George Washington - 1789 | |||
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Found a copy, and it's on its way. | |||
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I'm a fan of heavier bullets of good construction with a proven track of reliable expansion. I shoot: 150g Partitions in our 270s. 300g A-Frames in our 375 570g A-Frames in my 500 Jeffery though I wish they made a 600g They all seem to work. Regards, Chuck "There's a saying in prize fighting, everyone's got a plan until they get hit" Michael Douglas "The Ghost And The Darkness" | |||
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Saeed put it very succinctly, but controversy still continues...this is NOT about what the bullet actually does but about defending a position almost to the death...."THIS IS WHAT I BELIEVE, I HAVE PROVEN IT AND IT'S SHOTGUNS AT 10 PACES IF YOU DOEN'T LIKE IT." Whether or not two authors are right or wrong or just out to make a buck is totally irrelevant...I can safely say that NO bullet has read all the millions of tons of BS written since the Chinese invented gunpowder and once the trigger is pulled all bets are off because the bullet will do what the conditions dictate...THEORY be damned...and what only two authors think...there are MANY books written on the same subject...it's all about conditions and the instantaneous time/point the bullet hits something and all that nice theoretical stability goes to shite. This concept get proved EVERYTIME A bullet enters a mammal yet that theoretical krap IS SO ENGRAINED IN THE PSYCHE of hunters they continue to cling to that old adage and if the bullet isn't a perfect example of what is posted in pictures in periodicals, the bullet is a POS...doesn't matter that the beasty is dead because if it wasn't HOW could they dig the bullet out...I mean, come on, isn't this bullet "this vs that" getting a bit old...and TOTALLY UNPROVABLE BEYOND A CERTAIN UNDEFINED POINT. I can ALMOST guarantee that soon after gunpowder was invented and the means to stuff it down a bamboo tube and add SOME KIND OF PROJECTILE AND IGNITE IT, a scribe somewhere was writing about what the BEST projectile was and another was writing that is wasn't and "this thingy pooh was much better because, ta da, ta da, yada, yada, yada. Defending a position...I"M RIGHT AND YOU'RE BANDTA POOH...PERIOD. EVERYONE has their favorite bullet for specific game, and EVERYONE thinks that some bullets are shite...and EVERYONE can't seem to NOT argue over it...and NO ONE is proving anything other than the more sundowners that go down the more heated the dust-up can become which just hardens positions even more and who even cares because I'm right and your....circular and catch 22...and WHO even cares because I'm....yada, yada, yada...and we want to argue till hell freezes over.    I've shot enough game and I have a very curious mind so what one or a few authors say is only useful insofar as I can semi-replicate the results...so I don't do the "blame game" per se except to try to determine what actually happened. I HATE TRACKING so I want the animal to die as quickly as possible because it if doesn't the game can taste very bad if edible at all. I like to eat right up to the hole/holes so I fit the bullet AND conditions to the game...i.e., I have my own choices and NO ONE tells me which bullet to use, I do the same to other hunters and leave off the arguments, they are a waste of time...I would rather enjoy the evening and the camaraderie, watch the fire and listen to the night sounds and not hot air. EVERYONE has choice...keep using what you like or if it doesn't perform to YOUR satisfaction there are hundreds of others to pick from...do it or don't...all the rest is just smoke and mirrors. Luck | |||
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Penetration and expansion are opposites. You take one or the other. but you can split the difference, and in time that is what most will do... I chose penetration because its a sure killer but not the fabled DRT. it waste less meat, it is a surer killer, albeit with runs up to 100 or so yards.. Expansion is the quick killer and its awesome but you cannot depend on it, it makes bullets do funny stuff moreso than heavy jacketed bullet and animals can run miles then crawl up in some thick stuff and die in a day or two.. So the fabled dead right there (coined as DRT) is nothing but fallacy in my book..Not all animals die right there, and anyone who makes that statement just has not hunted a hell of a lot, as animals normally run after being shot The 222, 223, 22-50 and 220 swift are the fastest killers of deer I have ever seen, they kill them on the spot most of the time, but I will guarantee you that you will lose a deer on rare occasions if you keep using them..If you havn't then you will. At best it will teach you take easy close shots, even then you will need fast follow up shots at some point. All that said, if its legal, then the choice is yours, but its a terrible feeling to lose a wounded deer or whatever. Ray Atkinson Atkinson Hunting Adventures 10 Ward Lane, Filer, Idaho, 83328 208-731-4120 rayatkinsonhunting@gmail.com | |||
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The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Rifles Big Bores Who's correct regarding penetration of softs? Art Alpin or Pierre van der Walt
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