It was inevitable that this topic should come up again in my blog writing. “How so?”, you might ask. Just because: 1) I want to talk about it again; 2) It needs further clairification in my view; and 3) “New” and “better” bullets are constantly being promoted in outdoor magazines, plus in promotional videos with well-known gun writers using them.
This will be a very short refresher course only. Some time ago I wrote extensively on my results from various tests of .458-caliber projectiles, with photos. This will be a repeat performance with added commentary.
The MEDIA used: I believe it’s obvious that results will be determined in large measure by the test medium employed. I’ve used a natural earth bank background of fine silt, gravel and stones – then dug out the bullet remains. Also, I’ve simulated that in a plywood box of a like mix. And bullets have been dug out of the the 100 yard berm of natural earth behind the targets, which included thousandths of fragments of bullets mixed with the soil. Then various pieces and types of wood have been used along with a variety of paper medium. Finally, some bullets have been retrieved from the corpses of animals. All have a story to tell.
IMPACT VELOCITY: One should not underestimate this vital factor. The same bullet from the same rifle and load may have a different story to tell at various ranges on the same animal. Promotional material from bullet manufacturers most often want us to believe that regardless of range or impact velocity – within prescribed MVs – their bullet for BG will get the job done if the shooter does his/her part! There’s some truth there, but NOT the whole truth! At diverse ranges there will be distinct impact velocities and momentum, which affects bone and tissue variously, but also, bullet expansion is directly affected as well as retained weight. Then penetration will vary as well as cavitation depending on how bullet structure endures and reacts to assorted pressures and stresses.
“The more it cavitates the less it penetrates” – a quote from somewhere that gives a general principle. But of course, there are exceptions to general principles. Energy is carried by the bullet and is transferred to the medium either in large cavitation or deep penetration, or an expression of both depending on bullet profile and construction. Either way, it should be numerically quantifiable in a comparative context to have intelligent meaning for the shooter or observer. Normally, that is by wound volume. Wound volume is critical, but location is more critical!
So how do we quantify wounding before the fact? Estimation could be done in at least one of the following ways:
1) Kinetic energy (KE) at impact – historically, an accepted method but largely rejected today by experienced hunters and shooters.
2) A compilation of mass X velocity X caliber/7000 = the KO formula, or some variation of that theme.
3) The TE formula = KE at impact (KEI) as a separate function before multiplication with Sectional Density (SD) X cross-sectional area of bullet (CSA) = TE (Terminal Effect) This gives added significance to KE through the introduction of both the sectional density and cross-sectional area of the bullet.
For example: 2000 ft-lbs of KE from a 500gr/.458-cal at impact in a vital area on a game animal. Of course, depending on the BC (ballistic coefficient), MV and range, 2000 ft-lbs (or any other KE number) will be determined. It turns out that the impact velocity of that 500gr/.458″ that produces 2000 ft-lbs of kinetic energy would be 1342 fps at 248 yards when started at 1850 fps with a BC of .300. (In the region of my hunting, spring or fall.) Remember: MV, B.C. and range will determine that. That can be calculated. You will need a ballistic program available to calculate this. Then multiply (separately from the KE formula) 2000 x .341 (SD) x .165 (CSA of a 500gr/.458 cal) = 112.5 TE.
Here is a comparison with a .30-06 making 2000 ft-lbs of kinetic energy at bullet impact on large game: a .30-cal 200gr (Partition or any other 200gr, .30-cal) will produce the following TE, and range will be determined by MV and BC. In this particular case it’s: 2000 x .301 x .074 = 44.5 TE @ 336 yards when that 200gr Partition is started at 2688 fps (Nosler’s results from a 24″ test barrel) and .481 BC. (In our typical conditions for spring and fall). At the same range (336 yards) the 500gr load above would have a 91.6 TE at 1211 fps and 1628 ft-lbs. 1211 fps from a 500gr has 43% more momentum at impact and about 2x the TE of the 200gr, and 2.23 times greater in CSA! That explains the distinction between the two even though 1850 fps MV for the 500gr is only 80% of the maximum possible from a 24″, .458 Win Mag.
I chose 2000 ft-lbs, an arbitrary number for large game of approximately 1000 lbs because that was recommended in a previous era by a Conservation Officer in a training program for new moose hunters. And 2000 ft-lbs at IMPACT from any BG rifle! Also, around the same time (about 40 years ago) I read an article in a prestigious hunting magazine that said about 2900 ft-lbs from a BG rifle was recommended for brown bear at impact! That was an era when kinetic energy (KE) was king! Since then I’ve learned a few things on my own and through more reading and research – like results of tests by CO’s in Alaska for various cartridges suitable for brown bear. They gave a value for each depending on bullet performance. It turned out, in that particular study, that the .458 Win Mag was number one! Why? Their results were based on KE at impact, weight retention and penetration.
Yet nice pictures of expanded premium bullets at various impact velocities in a magazine add is no guarantee of like performance in game at various ranges due to several variables. An elk hunter with much time and experience under his belt in a variety of conditions already knows that – as one example. There are 400 lb elk and then there are 800 lb elk. They may be the same species but are not the same animal! He or she “experienced” elk hunter already knows they must be prepared for the 800 lb elk at any angle and range! So it is with moose and such other African, Australian or Asian game that may greatly differ in size and circumstance.
ANGLE of Impact: Nearly 100% of professional testing uses calibrated ballistic gel or water. In a highly controlled environment it’s relatively easy to produce perfect “mushrooms”. Bullets entering controlled materials from directly on at 90* will rarely show distortions to the bullet or tumbling. But give the same bullet a 30* to 45* impact angle and let’s see what happens! Add a few heavy bones to that mix and the “rules” fly out the window!
Following are some pics of bullets that were significantly distorted enough to “change the rules”:
1) A 350gr TSX/.458 cal that impacted the test setup at about 2400 fps. It penetrated the hard cover books and dry magazines without expansion until it came in contact with the edge of a 1.75″ softwood plank. It was lost somewhere in the earth background for about a year when found by using a metal detector (see pic). Contrast that with the other 350gr TSX that stopped just inside the last panel of the second box after having cleanly penetrated two 1.75″ softwood planks.
< Left to right: 1)the 350gr TSX that remained inside the second box; 2) a never fired 350gr TSX; 3) the 350gr TSX that was retrieved a year later under soil; 4) a 300gr TSX/.458 fired from the same Ruger No.1 in 45-70 LT at an impact of 2600 fps into a media of books and dry magazines. The force of that 300gr TSX, that only penetrated 8.5″, drove the remaining 10 inches of dry magazines through the back end of the cardboard box, ripping that panel loose, and scattering magazines across the snow behind! The full box of media was also slid about a foot backwards over the snow! In other words, don’t try to catch a 300gr TSX coming your way at over 2600 fps! There’s a great deal more to be learned from bullet testing than kinetic energy and penetration only! A large part of those events involving the 300 TSX was caused by the bullet’s momentum.
2) A 286gr/9.3mm that killed a bear but tumbled in the process and ended up going backwards:
<The “wings” bent forward are proof of that bullet travelling backwards at some point after initial expansion and losing it’s front core. The shot was frontal chest as the bear faced me from about 68 yards. It was in tall, uncut grass with only it’s head and a very short part of it’s neck visible. I aimed just below that for the heart. The bear disappeared at the shot in the tall grass. When I got down from the tree stand and walked to where the bear should have been, it wasn’t there! I did a quick scan of the area and found him dead at the bottom of an embankment about 20 yards away. He was a relatively young bear with little fat, and measured six feet from nose to tail.
The bullet worked at +2600 fps MV and around 2500 fps impact velocity, but should have given better penetration in my view. It fell from the right flank in skinning the bear next morning. The fact that the bullet tumbled was somewhat concerning to me, but it retained 73% of initial weight at 210 grains. So everything isn’t just a neat package according to “the book”.
Unseen OBSTACLES: What happens to bullet “A”, that has “proven” itself multiple times according to promotional material and some “clients”, when it hits, sideswipes or glances off a twig, small branch or other unseen impediment in flight to the target animal? Well, the truth is that almost anything unexpected could happen from not hitting the animal at all, to the bullet hitting where it wasn’t aimed, to a “key-hole” impact, to… you name it! What about shooting through brush? Obviously, we see those results!
The question is: Are some bullets and calibers better at staying on coarse than others? Are heavy bullets better than lighter ones per caliber if hunting in wooded or brushy conditions?
I’ve had a few experiences – and I’m very happy that they were few! But sooner or later it will happen to most hunters who hunt in those conditions. Are there bullets that can “bust brush” and kill the animal behind it? Etc.
All of my hunting over the past sixty-plus years has involved some brush or trees to heavily wooded forests! The one exception is the small game hunting of groundhogs in open pastures. But even then, woodchucks have a habit of digging burrows and travelling from place to place in hedges and tree lines that mark out pastures and property borders. So it’s not always “clear sailing” in the pursuit of those critters!
Despite many articles that have sought to prove that NO bullet or caliber is immune from deflection when the bullet hits, strikes, glances off of some obstacle on it’s path to terminate a game animal, many of us still think that a heavy bullet from a large caliber rifle at relatively high velocity will reach its mark on a relatively large game animal. Why so?
First off, let’s examine some bullets. Are long for caliber bullets inherently less stable? Of course, agreed, a lot depends on MV and rate-of-twist. But it is generally agreed that some of today’s long monos in particular calibers need a faster-than-normal twist ratio to not only maintain stability in flight but most importantly to maintain stability during penetration! I buy that for a number of reasons, not the least being some personal experience as well as the expertise of some others for whom I have high regard. Then too, some professionals who build rifles and/or bullets have made recommendations to the same effect. For instance: Why does a 7-08 Rem need a 1-9.5 twist rate barrel? It’s really quite simple: Someone, somewhere just might decide to use one of those long 175gr beautiful bullets with the sharp nose in their 7-08! And, moreover, since the MV of that bullet will not be “beautiful”, it will struggle to maintain balance even in “thin” air as the velocity drops! But that same 175gr will prove its worth at 3000 fps MV! So: MV, caliber, rate-of twist, bullet weight and length, SD, impact velocity and angle of impact all are players in bullet stability to begin with!
I notice that, according to African YouTube hunting videos, most hunting is in relatively thick veld. And often shots are taken, at the direction of the PH, on animals (sometimes big and dangerous) where and when I’d never take a shot on a game animal! In other words: on animals partially obscured by thick brush or trees! So shooting has to be very precise in firing through a tiny hole through the bush to hit a vital area of the beast! Under such conditions, either you shoot or go home empty! And usually heavy bullets for caliber are loaded.
I once shot a bear using an original 200gr X-Bullet. It was a “trophy” quality bear but the sequence wasn’t pretty! The bear was lost in the darkness and a followup the next day by three of us produced this: pinpricks of blood, a 2″ strip of fur and hide, and many hours of trying to track the bear down, which ended in frustration. On my own, I went back to the scene the following day and discovered a small hardwood sapling about an inch thick had been hit by that bullet and lopped off about fifteen feet before it hit the bear somewhere other than intended. And I’ve good reason to believe that the bullet tumbled in hitting the bear. The rifle cartridge was .35 Whelen, and a 200gr only has a sectional density of .223 for a bullet that was about 1/3rd longer than the Hornady 200gr SP. Barnes doesn’t anymore make a 200gr TSX in .358-cal. I’m convinced that a roundnose Hornady of 250 grains at 2500 to 2600 fps would have served better even if it hit that sapling.
Would a 480gr/.458-cal of suitable construction be a better choice for large and potentially dangerous game in Africa, in the conditions previously discussed, than a well constructed 350gr? The 480 has an SD of .327 and the 350 has an SD of .238. Which would defeat light brush better when started at their “normal” MVs?
Bullets RETRIEVED from game: This has been lightly discussed above with a couple of photos. But there’s little doubt in my mind that, while I like testing in media, bullets retrieved from animals have a story to tell that’s totally unvarnished. Here’s a pic of some North Fork 300gr solids. The one on left from an elephant shot by Bob Fritz using his .375 H&H.
And another taken from a grizzly shot by “Yukoner” Ted in the Yukon using his 9.3 x 62. It’s a 270gr custom from B.C.
And this from my first bear: a 400gr Speer from a Marlin .45-70 at 1865 fps MV and about 1535 fps impact. It retained 90.5% of unfired weight. A “premium”?
And still this from a bear shot by a friend using his .35 Remington and a handloaded 200gr CorLoc:
Full-PENETRATION: The bullet from this bear was not retrieved as it went cleanly through taking out lungs and heart before exiting between chest and left front leg leaving a blood trail that no one could miss! The bullet was a 250gr Accubond from my 9.3 x 62 at 2700 fps MV and impact velocity at about 2540 fps/3580 ft-lbs.
So “bullet testing” results are verified by ALL of the above “witnesses”, and not simply by shooting some into a box of “media” at a fixed distance and MV!
Simply stated: We review and carefully examine ALL verifiable “witnesses”, including our own results, to determine what bullet appears more than adequate, or even best, in consideration of most probable variables, for the proposed BG hunt!
I wouldn’t fuss over bullets for varmints or medium game – almost any of today’s “suitable” bullets will “kill” varmints and small to medium game IF one can “shoot”! “Premiums” are NOT needed — so don’t wast $$$ on what you don’t need!
So also cast bullets will do this and more:
‘Til the next…