Book Chapter 8-Home

Hunting Bullet Metrics

Apply Terminal Performance Truth

AFRICA HUNTER QUEST©

Chapter 8 - THE PILGRIM READS THE SIGNS

Donny walked to his truck. He was irritated and disgusted. A complete waste of time. The Old Man wanted to talk in factoids, parables, and riddles. That being said, he ruefully had to admit that he was being forced to think, and he didn’t like it at all. There was no external validation nor opinions from others. In effect, there were no ‘likes’, ‘dislikes’, or ‘reviews’ from postsperts tabulated on a screen. He was on his own. Or was he?

Donny thought about the first questions GG had asked: “Have you at least ordered Robertson’s book?” At the time, he had no idea who or what Robertson was. Assuming GG was right about Robertson’s credentials, what he had to say might help organize and clarify the multiple concepts he had just been force fed, maybe even give clues about how they could be knitted up. When he got home, he got online and reluctantly ordered a copy of Robertson’s second edition.

While he was online, he briefly cruised hunting forum web sites to see if he could pick up any clues that would be helpful in solving his 270 Winchester puzzle. As he searched the threads and posts, he began to suspect that he was typically finding considerable clueless instead of clues. Some had such strident opinions and defended them to the point that if those opinions were a truck, those boys would rather push their own rather than, God forbid, drive a different one. Stubborn? Definitely. He smiled. “Know thyself, Pilgrim.”

He again thought back to his encounters with the outfitters in Harrisburg. He had talked with PHs just like Robertson. They had all indirectly given thumbs down to his 270 Winchester. Maybe Robertson’s book would help him to understand why.

What had been their responses for a recommended chambering for a kudu? A 7-mag with a 175-grain bullet, a 30-06 with at least a 200-grain bullet, a 7.62x51 with a 165-grain solid copper bullet, and a 35 Whelen with a 250-grain bullet. Since the PHs had not given a 270 Winchester as their first response, and because the empiricism GG had given him yielded an estimated plains game weight of only about 405 pounds at the muzzle, it was probably safe to assume that these recommended chamberings and bullets would result in a higher estimated game weight using GG’s empiricism.

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Donny got online and searched the internet for representative muzzle velocities for the chamberings and bullets the PHs had recommended. He found a value of about 2900 fps for the 7-mag’s 175-grainer, about 2700 fps for the 30-06’s 200-grainer, and about 2500 fps for the 35 Whelen’s 250-grainer. He was temporarily stumped by the 7.62x51, but discovered it was nothing more than the metric equivalent of a 308 Winchester. It was easy to find velocities associated with a conventional 165-grain bullet, but not for a solid copper one. He persisted until he found 2700 fps for a 165-grainer.

He got out his calculator and punched out the estimated game weights at the muzzle using GG’s empiricism. To his surprise, all but the 308 Winchester had values greater than 600 pounds, the weight of an excellent, trophy-grade kudu bull. The 308 Winchester with the 165-grain solid copper bullet was only about 550 pounds at the muzzle. He had not asked about typical shot distances that would enable him to use online ballistic software to calculate impact velocities. Regardless, the estimated weight was going to be less than 550 pounds for the 308 Winchester and 165-grainer when any impact velocities were considered. Why was the 308 Winchester and the 165-grain solid copper bullet combination considered satisfactory?

Other than the 308 Winchester, the other three chamberings could be assessed to be sufficient to kick a$$, with the 7-mag at about 670 pounds, the 35 Whelen at about 1170 pounds, and the 30-06 in between at about 810 pounds. Although he really didn’t want to concede any credibility to GG, the correlation with what most of the PHs had told him and GG’s empiricism results was surprisingly good. Even the 308 Winchester outlier was in the ballpark, probably reasonable given that four different people had given him four different answers. One rifle-and-bullet combination was way conservative, two pretty much on point, and one on the light side.

Those assessments were only valid if GG’s empiricism was also valid. A quick Matunas calculation put the 308 Winchester at a comfortable 800 pounds or so, the 35 Whelen at over 1450 pounds, and both the 7-mag and 30-06 in the 1100-pound range. If Matunas’ empiricism was valid, everything but the 308 Winchester was way too much gun. Still, he would give Robertson’s book a peek to assess if either of these or any formula made sense. His conversation with GG had cast doubt that any formula, empiricism or otherwise, could account for all the factors embedded in hunting any animal and still yield a believable answer.

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He then found a web site with information about Dr. Fackler. Damned if the wound cavity sketches didn’t look like finless guppies! Like GG said, the cavity shapes didn’t conform to just a hole that a bullet would make. “Damn him,” thought Donny, as he smiled at the guppy shape on his screen.

Robertson’s book arrived in a few days. He looked at the Table of Contents and was pleased to see there was an entire chapter dedicated to kudu. He completely ignored GG’s advice about reading the first five chapters and turned to the kudu chapter. The first five chapters that Robertson had labeled “Part One: The Basics” could wait. Damn it, he wanted answers.

He scanned the chapter, quickly noting that there was a broadside anatomical picture of the kudu that showed its skeleton, lungs and heart. In glancing at the picture, he saw that the lungs dropped down over the heart, completely enveloping it. He then zeroed in on the chapter section titled “Rifle, Caliber, and Bullet Selection”.

The more he read, the more disappointed and frustrated he became. Robertson talked about kudu being taken from relatively short range in brushy conditions (at least that’s what he thought bush-veld meant) out to 300 yards in open terrain. He only talked about using the 270 Winchester for shots on the order of 300 yards, not for shots in brushy conditions. Hell, it wasn’t even considered for those short-range shots! Why was a 270 Winchester considered for a 300-yard shot and not for one way closer? It didn’t make sense.

For a 300-yard shot, Robertson talked about using a 150-grain premium bullet. There was that term again, ‘premium bullet’. No brand names were furnished for bullets needed for these long-range conditions. Instead, Robertson talked about needing high ballistic coefficient boat-tail spitzers just like he was shooting. Not only did Robertson’s omission of using a 270 Winchester in brushy terrain make no sense, he had left too many blanks to fill in for what he considered satisfactory long-range bullets. In short, Donny was really no better off than when he started, plus he was out the cost of a book.

His reading and subsequent disappointment had put him in a ‘thank you, sir, may I have another’ mood. If there was any more bad news, he wanted it all out in the open.

He went online to see what 270 Winchester ammo was available with a 150- grain bullet, spitzer boat-tail or not. He found 15 different ammo choices with 150-

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grain bullets, but only three that used what looked like pointy, high BC boat-tail bullets. Muzzle velocities and muzzle energies were catalogued, but no bullet BCs were furnished. He was forced to research the 150-grain bullet BCs on manufacturers’ web sites.

The 150-grain bullet from the same manufacturer as his 130-grainer only had a BC of .521, not even close to the best. He was encouraged, however, that the 150- grainer from the manufacturer of his 130-grainer had the picture of an elk next to it, indicating that it could be used to take an animal that large.

While cruising the bullet manufacturers’ web sites to find BCs, he discovered that one made a 165-grain bullet in a .277 caliber. The BC for this 165-grainer was .620. The manufacturer indicated that its optimum performance velocity range was from 1300 fps to unlimited. The game recommendations included deer, moose, and African game. Donny wasn’t really interested because he could find no ammo manufacturer that loaded this particular 165-grain bullet.

Donny went to the website containing the software that he used to estimate the trajectory of his 130- grainer. He knew he could get velocity data at 10-yard increments out to 300 yards. He plugged in the stated muzzle velocity and BC data for all the long-range 150- grainers and determined that the impact velocities at 300 yards would likely range from about 2395 to 2540 fps. Predictably, GG’s empiricism only indicated animal weights from about 404 to 428 pounds, while Matunas’ empiricism predicted game weights from about 465 to 553.

Donny was befuddled by the results. Matunas’ empiricism indicated that at least one manufacturer’s ammo gave an optimum game weight of 553 pounds at 300 yards. That pretty much proved that Robertson’s recommendation was dead on, even for a chambering and bullet considered to be lower bound. If that was so, why wouldn’t this same ammo work at way less distances in the bush? Who and what was credible? Who was giving the good advice?

Too many questions. No definitive answers. Too many decisions. He decided to call his dad for help in sorting all this out.

His dad was thrilled about the potential trip to Africa, and immediately offered to let Donny use his 30-06 Ackley. Donny ignored the implied opinion about his 270 Winchester and immediately asked his dad if he thought his 270 would work for taking a kudu.

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The extended pause from his dad before answering spoke louder than his delayed reply of “Might be a tad light.” Donny knew that if he had asked the same question 25 years ago, the answer would have been “Hell no!” That his dad continued on about finding two unrecovered elk in the process of being picked clean by buzzards and coyotes put an exclamation point on his otherwise PC answer. Donny knew that his dad was using this scenario to tell him that there were better options than his 270 Winchester.

To his dad’s credit, he didn’t beat Donny about the head and shoulders with accounts of how good his 30-06 Ackley and 200-grain bullet had performed. Instead, he told Donny that when he was evaluating bullets he was considering for hunting elk, he discovered that the manufacturer of the bullet he subsequently selected made a 180-grain bullet in .277 caliber. Donny knew that he had, again, been given a hint and left it at that. Donny had absolutely no interest in the potential hand-loading ordeal associated with bullets greater than 150 grains.

The negative vibe about his 270 Winchester was now coming from four sources: the PHs in Harrisburg, GG, Robertson, and his dad. Tough to ignore, even with favorable Matunas calculations. There was simply too much smoke for there not to be some kind of fire. He had a renewed suspicion that no formula, empirical or otherwise, could give a reasonable prediction of approximate game weight, given all the variable factors involved.

Of the four, GG had been the least accommodating in terms of even considering the applicability of his rifle and ammo, as well as providing what Donny considered to be strategic, focused guidance. In some ways, the Old Man came across as autocratic and put-upon. Donny felt like he was never on an equal footing when discussing any issues with the man. The only reason Donny was even fooling with GG was because he was reputed to have gone to Africa multiple times and ought to have easily answered his one simple question.

In a flash of enlightened embarrassment, Donny then realized that GG had, indeed, answered his question as tactfully as he likely knew how. Instead of saying “no”, GG had given him tools in the form of a book and empiricism to discover ‘the answer’ for himself. His admittedly stubborn nature had him bowed up over what everybody and everything was trying to tell him ‘the answer’ likely was. He had opted to essentially argue with someone who had taken time to try to help him. At least that was one scenario that explained where and how things had progressed. What was it that GG had said at least twice? That it was Donny’s problem to define and solve?

Donny found himself fixated on the word ‘define’. “Holey buckets,” he thought. “Define the problem. Wasn’t something as simple as likely shot distance a fundamental aspect of defining the problem?”

He had never asked and didn’t know. He had been so fixated on an ‘answer’ using a formula that he had never gotten beyond muzzle velocity.

Donny had printed out results from the ballistic program he had used to estimate impact velocity at 300 yards. He now stared at the entire sheet instead of fixating on the velocity at 300 yards. The impact velocities had been calculated at 10-yard intervals. What was it that GG had been talking about concerning impact velocity? Wasn’t it fundamental for assessing terminal bullet performance? Why was it that he had only seen one manufacturer that had only partially furnished actual recommended impact velocities for their bullets?

Donny sensed that everything he had just thought about needed to be considered in defining his problem. He didn’t know precisely how to go about it. However, he was now certain that GG had been trying to point him along some sort of decision path that he had steadfastly refused to follow. GG really hadn’t been yanking his chain . . . well, maybe just a little today. GG had simply been trying to give him what he believed were the applicable tools and concepts to figure out his problem even though they were at odds with those considered as accepted and mainstream. This latest concept dump on defining and understanding wound cavity volume was apparently another tool that was fundamental in his hunting problem definition.

With a new-found perspective of GG, Donny read and reread the first five chapters of Robertson’s book. There was much to absorb. GG had been right: the preferred aim point on most African game was on the shoulder, rather than the lungs. The reasons made sense: the objectives were to both debilitate the animal’s mobility and preferably take out both the heart and the lungs. Like GG said, it increased the chances of a recovered animal, although Robertson never came right out and said it. Robertson made no mention of meat damage, and Donny kindly now knew why.

Robertson literally highlighted that shot placement was more important than caliber. Yet, later on he mentioned that “the caliber was in relation to the animal’s body size.” He identified recoil as the reason for poor shot placement. But what had GG said? Not enough man? Wasn’t the resultant recoil embedded in a ‘proper’ chambering and bullet caliber?

Robertson introduced the concept of wound channel and tied it in with caliber. “Bullets too small in diameter, even though they have the ability to expand to a larger frontal diameter, cannot be relied upon to consistently produce wound channels large enough to insure a quick death in a large body animal.” He also indirectly tied it in with bullet performance in terms of expansion and its ability to penetrate. He repeatedly used momentum and Taylor’s KO value to explain bullet penetration and effect on game, with more being equated to better. Donny concluded a heavier bullet in the same caliber would likely have more momentum and was thus better able to potentially both stop an animal and penetrate more. What he read later on assumed that the bullet wasn’t destroyed and performed satisfactorily. Was that somehow dependent on impact velocity and the design of the bullet? Wasn’t ‘satisfactorily’ a word he had pretty-much choked on in his last conversation with GG? “Looks like I need to figure out what that word means in terms of terminal performance,” thought Donny.

Concerning wound channel production, Donny read that the wound channel diameter produced by a properly expanding hunting bullet was up to 3 times the mushroom diameter. Robertson said that the greater the final diameter of the bullet through the heart and lung area, the greater would be the permanent wound channel and the death would be quicker. Wasn’t GG’s fixation on the importance of what he was calling a wound cavity echoing Robertson’s discussion of wound channel? GG’s assertion that the relevance of actually measuring the wound cavity volume to assess a bullet’s terminal performance capabilities was apparently being corroborated by Robertson’s skinning shed autopsies. “Although these boys use different terms, they seem to be runnin’ in the same rut,” thought Donnie.

Robertson identified bullets that he said had good reputations in Africa gained from repeatedly performing well. Donny noted that he never directly called any of them ‘premium’. It was disconcertingly obvious that the manufacturer of his 130- grainer wasn’t even mentioned.

Donny put down Robertson’s book. Issues, inter-relationships within issues, and potential solutions were becoming clearer. Damned if the Geezer hadn’t given him good advice. Still, he knew he couldn’t knit it all up without help. He also recognized that GG could help him better define the hunting problem based on his Africa experience.

He decided to pay the Ol’ Boy another visit, armed with at least a rudimentary vocabulary, strategic conceptual questions, and a better attitude. In the mental

gymnastics of the day, a random thought had contained the word ‘path’. Up until now he had felt like a hamster on its little Ferris wheel making it spin round and round. He figured ‘path’ was a pretty good word, and he might even be on one.