Thursday, May 28, 2009

Terminal Ballistics and Hunting

© 2009 Albert A Rasch
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Terminal Ballistics and Your Hunting
(Or why I like big bores so much.)

Weatherby Eurosport in 30/06,
my light rifle.

One of those things that I’ve never understood is how someone could spend hundreds of dollars on a rifle, spend the same and sometimes more on a scope, and then pick up a box of the least expensive ammunition they can find. Not that there is anything intrinsically wrong with such an approach, but when a hunt can cost you thousands of dollars in incidental costs, what’s twenty more dollars?

With that in mind I thought I would discuss terminal performance.

What a bullet should do:

There are two ways that a bullet works, either by punching a hole through a vital zone or disintegrating inside and destroying the same. The fact is that given sufficient disruption of a primary system, death will occur, therefore a projectile works by stopping or damaging a vital life support system and causing death by suffocation, shock, or central nervous system shut down.

A bullet should reach its target unerringly, penetrate and do what is desired of it. Varmint hunting prefer to have the projectile blow up inside the target and expend its energy within. Medium and big game hunters vary in their desire for controlled expansion. Bullets shouldn’t be expected to do everything regardless of circumstances. At close range some bullets just won't hold up. At long ranges some won't do what they're designed to do.

For handloaders, there is one bullet that qualifies for the do-all-to-end-all. (In my opinion anyway!) That would have to be the big-bore hardcast LBT style bullets. Close range to long range they make a hole and keep on going. Just ask the buffalo runners of yesterday.

Design:
Image Credit: Tonyolm
270 Winchester FMJ, Pointed Soft Point, Ballistic Tip

Today the trend is towards deep penetration and retained weight. Originally, the Nosler Partitions, and now the Swift A-Frames, and the Failsafes are the yardstick by which all other bullets are measured. I will get to solids shortly. Since I am predominantly a hog hunter, I can speak with some confidence as to what works and what doesn’t. If we limit our discussion to larger pigs of 225 lbs or more, the need for quality bullets becomes apparent. I have observed that at about 150 lbs hogs start to develop the shield and by the time they are about 225 the shield is now a hardened gristle deposit.


Imagine, if you will, a hollow-pointed bullet hitting that. The expanding bullet drives into this dense, inelastic material. The bullet expands rapidly in this material and loses velocity. At some point it starts to shed pieces and loses mass. Without additional mass driving it from behind, penetration slows dramatically. In all probability it never penetrates past the gristle layer. What you get is a surface wound, little to no blood trail, and no hog.

160gr Soft Points
The reason the 30/30 has taken so much game, is that it throws a 150gr softpoint at a moderate velocity. It hits, expands, and the long bullet shank goes on its merry way. If you shot the same bullet out of a 30-06, at the same ranges as a 30/30, it might not hold together. Too much speed and not enough jacket strength. So it is also important to match the projectile to the cartridge parameters.

A non-partition softpoint doesn’t expand, as much as it is disrupted by the initial impact. In this case, mass directly determines penetration. The heavier the softpoint, the more likely it will penetrate deeper. The original Barnes made its money with its softpoint line. Heavy for caliber bullets (How about 600gr 458s and 250gr 308s!), driven at moderate speed disrupted well, retained 80% of their weight and drove deep. The only problem the Barnes Soft Points ever suffered from was over-expansion and the commensurate deceleration, which limited penetration, and on very large game sometimes the softpoints failed to smash through bones.

XP3 Bullets
Now if you will, try the same scenarios with a Failsafe or XP3. The momentum afforded by the encased base allows the bullet to continue through the gristle and bone, and drive into the vitals.

Solids work by penetrating deeply and displacing tissue. Certain designs are meant primarily to drive through bones or large masses of flesh and muscle, like the Woodleigh Sledge Hammer, Barnes homogenous, and the AGS by Speer, which I understand is the best solid commercially available. These bullets are designed to drive deep, drive straight, and smash their way through anything intervening. In the hands of an excellent shot, a solid will reach the target it is intended to. “Karamojo “ Bell used solids almost exclusively in his .265 and .275 for all the game he took, dangerous or otherwise.

The latest take on solids, is the LBT style hardcast lead bullets. They are heat treated to make them tougher than they would otherwise be. They penetrate deeply, creating massive wound channels. They are accurate within their own parameters, and are available in number of calibers from 30 to .510. I use them in my 45LC and 458WM.

It has always been my preference to lean in the direction of greater penetration. Since I’ve always been suspect of my abilities, and hope to never lose an animal, I plan for the worse, and only take shots that I am certain of.

Shock:
The Weatherby line up.
In the late fifties and early sixties Roy Weatherby thought that if he could push bullets fast enough, the “hydrostatic shock” of the projectile moving through the muscles and tissues of an animal would be sufficient to cause instantaneous death. Two things worked against Roy’s theory. One, bullets at that time could not withstand the then phenomenal speeds at which the Weatherby rifles/cartridges shot them. Secondly, hydrostatic shock doesn’t work on large elastic masses. On the minimal mass of a prairie dog, it will, on hippos, no. It has been conclusively proven that bullet placement, not energy, is what kills. In the end it is the hunter’s ability to accurately place a bullet in the right spot that determines whether he is successful or not.

Stopping Power:
Image Credit: Jobe Roco
Classic, Old School Stopping Power!

Stopping power is directly related to the caliber.

Stopping power is directly related to the caliber.

There, I’ve said it twice. In other words, the bigger it is the more likely it will settle hash right then and there. As long as it has enough velocity to penetrate and all other things being equal, the larger the cross section, the more powerful the knock down capability. Empirical evidence suggests that weight, velocity, and the cross section of a bullet, determines its ability to knock down, that is to stun or immediately kill an animal. Pondoro Taylor and Hatcher both devised formulae and tables to estimate the knockdown power of any given projectile. They both weigh in heavily in favor of the bigger bores.

If you peruse the cartridge tables, you will notice two things, one, the big bore cartridges are slow, and two the projectile weights are high. When velocity is low you need mass and frontal area. Again empirical evidence suggests that when you are confronted with a mad Brownie, a 45-70 is better than say a 338WM. Otherwise why would so many Alaskan bush pilots prefer the Guide Gun and the Alaskans? The answer is the ability of a slightly souped up 405gr, .458cal solid bullet being able to traverse, end for end, an 800lb bear, smashing everything in its way. Wound channels are commensurately large in proportion with frontal cross section. As caliber goes up, the area goes up exponentially. A 30caliber bullet has a frontal area of .074 square inch versus .165 sq in for a .458, more than twice the area.

Image Credit: Keefs
Martini-Henry 577/450

Penetration:

You can never be certain as to what conditions will be when you have to put a bullet into the vital zone. The ability of the projectile to penetrate through any intervening meat, bone or viscera, into the vital zone is directly related to construction and design. Range and impact velocity also are variables to contend with. The lines are blurring slightly when one has to choose between a light quick bullet and a heavier slower one. Due to the better qualities of the newer bullets, it has become easier to drop in weight, add velocity and be confident of retained terminal weight. The 30-06 loaded with 150gr Failsafes shoots as flat as a Remington 7mm Magnum and will retain almost all of its weight. But retained momentum and energy are diminished substantially as the bullet weight goes down.

How should you decide? I am convinced that 90% of all game is taken inside of 100 meters. In the end all that matters is whether a bullet penetrated and did sufficient damage to kill quickly. If I was hunting Florida whitetails exclusively, and limited my shot to reasonable ones, I wouldn’t hesitate to use any of the commercial soft points. I would only choose the brand that gave me the best accuracy. Florida deer are small, and considering I do most of my non-hog shooting with a 30-06, there is no real need for a deep penetration. That’s a personal preference; at the ranges I am capable of shooting to, you could cut the end of the bullet off with bolt-cutters, and it would still hit the target close enough to point of aim. But if I were going to Africa (plains game), or to Arizona for elk, even white tails in Texas, I would use nothing less than Winchester Failsafe/XP3 or Remington Swift A-Frames. I would limit myself to shots inside of 150 yards, where I could be absolutely sure of where my bullets hit. I would familiarize myself with the game animal until I could visually dissect it and know where every vital organ lies. I’ve killed enough pigs to be almost certain of every shot’s terminal trajectory on them. “Karamojo" Bell did this with much success when meat shooting North American game in Alaska, and then in Africa where he made his fame shooting elephants for ivory. But even though I can visualize where the pig’s heart, spine, and liver lay, occasionally I am still surprised. Recently I took a shot at a small hog, aiming for the box made by the eyes and ears. Imagine my surprise when I recovered him and found that instead of a frontal head shot, I had made a side brain shot.

450gr LBT's
If you are picking your shots, and not picking fights or trying to stop them quickly, then it is reasonable to use any cartridge and rifle combination that is suitable for the game at hand. For instance, I think I am a reasonably capable shot with my Weatherby 30-06. Anything inside of a couple of inches is in eminent danger of being ventilated at 150 meters or less. With that in mind, I would not hesitate to use it with 180gr A-Frames against brown bears, and here is the operative phrase, if I had to. But I think I would feel better with my 458WM. At 100 meters I can keep all my shots within 3 inches. 450gr hard cast LBT type bullets at 1800fps, will double lung any grizzly, bust both shoulders, or traverse the grizzly end for end.

And If things somehow got ugly and I have to end a fight, I’ll be confident that between the 458 and I, we can swat one down flatter than a stray aluminum can on the expressway.

Regards,
Albert A Rasch
The Hunt Continues...

16 comments:

Wild Ed said...

Albert this goes against conventional wisdom but I have become a fan of the balistic tip varmint bullet for feral hogs and deer under 125 pounds. My daughter shoots a .223 and a 55 grain Nosler balistic tip right behind the shoulder on our Hill country deer. The bullet goes in and does not exit. All in the chest cavity is jello and they drop like a rock. I have had the same experience with feral hogs to 225 pounds with the same round. You must place the bullet but it works like a charm if you can shoot. ET

Phillip said...

Is that a vote for go big or go home?

I certainly don't disagree that bigger can be better, especially if you're shooting at something that might really eat you (hogs are a minor concern... it could happen, but it's not real likely). I'm generally happy shooting pigs with the -06, but I have to say the .325wsm speaks with authority.

By the way, the cast bullets were a rage here in CA with the handgun hog hunters, but with the lead ban we're dealing with a whole new critter. My handloaded Barnes for the .44mag are costing me somewhere in the neighborhood of a dollar and a half per shot. Haven't used one on a hog yet. Seem to do the same thing... drive deep and hold together without a ton of expansion.

Good stuff, Albert. I'd love to grab myself at nice .458 and the ducats to shoot it regularly. Until then, though, I'll just keep looking at that #1 in your picture up there and drooling.

Phillip said...

By the way, I used ballistic tips on hogs for a while. They're super accurate in my -06, and they killed the hogs stone dead... but the amount of lost meat was unacceptable. Never again.

hodgeman said...

Great post Al,
At one time as a neophyte deer hunter I bought multiple boxes of 30-06 115gr Silvertips on big discount at a wholesaler (wonder why?). No idea what the velocity was but I'm sure it was well over 300fps in my 26" barreled rifle.

I discovered quite by accident that on behind the shoulder lung shots those things killed deer like lighting bolts from Thor's hammer. Groudhogs would evaporate before your very eyes. I think I had killed 12 or 13 whitetails before someone finally told me I was doing it all wrong...never did get an exit wound. Never needed to track anything either, but I was lucky- a shoulder shot with those little bombs would have meant a long tracking job and a potential non-fatal wound.

The Weatherby reputation was built on high velocity and too soft bullets. In the right place they just smoked game like the finger of death. On a close shot they often experienced bullet failure resulting in a reputation for wounding. I think bullet technology has finally caught up with Weatherby velocities though.

Lately I've been messing with 180 TSX Barnes at 3000 fps or so out of a .300WSM. Should give "hydrosatic shock", an exit wound AND hold together. It also shoots flatter than griddlecakes for tundra shooting.

For more tangly terrain a bore you can cram a pinky in gives you a lot of comfort though. Might have to pick up another one of those...

tom said...

You might wish to read this as there are too many valid points made in it for me to make here in semi-agreement with you to put it in a comment. It's a long read but worth it.

These are my vote for "ultimate solids".

[To a particular hunting blogger who will probably read this, feel free to ignore this as I already know you have a blog of your own and we disagree on bullet performance and more people read your opinions than mine. I still stand by my opinions.]

Wild Ed said...

Tom I do not want to get a big head by thinking you are referring to me but I will be the first to say that I do not disagree with you and Albert about large calibers. I just do not hunt in country where it is needed and I will be the first to admit that after two shoulder surgeries I have a real problem with recoil. I am not ready to turn in my man card so I shoot light and fast small calibers with high shock bullets. They are not for everyone but work for me and the girls. I think if someone can handle the recoil and can shoot the big guns accurately they should absolutely use them. If I hit game in the shoulder socket with what I shoot I would have a tracking job and most likely need another shot. If you or Albert hit something there it will still go down. I can not take a glancing head shot with a 223 on a hog but need to be able to hit it in the base of the ear or behind the shoulder. A large caliber can hit it most anywhere and put it down for keeps. I say shoot whatever you are the most comfortable with and go hunting. In fact either one of you guys can back me up anytime. :)

tom said...

I wasn't referring to you. Somebody recently told me my new found preference for A over B projectiles was wrong and pointed out in his post about how my views are irrelevant because he is a "famous blogger" in number of hits and I'm nobody because I have less readership and comments on my blog...probably because I have a tendency to be blunt and subtle as a sledgehammer as I write my blog for me and people like him aren't my editor...Comments are often turned off, as well, as I got tired of moderating things where people tend to send lots of useless advisements.

Sorry, it wasn't you and for sake of propriety I shan't say who it was. He'll know who he is.

I killed a near 800lb zebra with a 55gr .223 SP with a head shot at long range once. You've got no quarrel with me. One of my .223 Contenders I just Ackley Improved and I forsee it getting a lot of use on game up to the size of white tail.

No quarrel 'tween us.

FWIW, I'll probably end up with bad arthritis from my hand cannon hobby. Doctor has warned of that and possible tearing my rotator cuff and/or upper back injuries, but they're fun, dangit!

tom said...

Semi-Relevant story:

Friend from gunsmithing college is a RSA national (he came here to study at gunsmithing school and then went back and opened his shop, one of the few people who amounted to anything out of my class).

He's a reserve policeman in Kwa-Zulu Natal and they had a rogue elephant. He was asked to come out and second for the duty policeman on dispatching the ele. Lead man made 3 or 4 proper head shots with .375 H&H Barnes solids, as I recall, and the ele was angrier but nowhere close to dead. As big as their heads are, their brain is only about the size of a soccer ball in all that bone. Chris seconded him with his .458 Lott with a GS FN 500 grainer in the brain region and the ele fell like a house of cards. One shot, game over.

The .375s had made it barely into the very outer portions of the cerebellum, the .458 GS went through the middle and out the other side of the brain.

tom said...

Oh, for Albert's amusement, I just found 5000 factory primed Eley manufacture cases of .500 Eley for a good price on offer and I don't know if you've looked at the CVA APEX yet (Sort of an ENCORE-alike with switchable barrels but sturdier, so they say) and they are selling them without barrels just like T/Cs if you like, and Bellm and perhaps somebody you know :-) have been using Bergara barrels lately (factory was set up by Shilen in Spain, nice stuff) which is who CVA is using to make APEX barrels...can you see a project coming together that won't quite rival my .458 Lott No. 1 but will definitely punt a large bore bullet out at a decent speed?

It takes a Tom to take a new 21st century firearm design and plot and orchestrate the stuffing of a late 19th century cartridge in it, aye? Reamers on the way...

Bet it'll knock a hog over.

tom said...

By the way, just for Esses and Giggles, somebody here needs to memorize this:

The erratic penetration of the premium non-bonded bullets at high velocity (>2800 fps) not observed in the other three clases, including a slight trend in some cases toward increasing penetration depth, results from the loss of expanded frontal area; either broken off petals in the case of monolithics such as the Barnes X-Bullet or else eroded frontal cores and fully peeled back jackets in the case of bullets like the Nosler Partition and Speer Grand Slam. Obviously, these are generalizations based on a single bullet weight and caliber and specific bullets will vary, but these trends are strong in this data sample.And I honestly did give away piles of Nosler Partitions for that reason as they were not reliable on HOGS in spite of the "famous man's" view. Silvertips actually work better in my non-humble experience. I'm nobody so ignore this if you are the person this is directed at.

I suppose I should use lower velocity or perhaps use the bullets and boolits that work for the velocities I aim for...being as it's my hunt and my job to track and dispatch wounded animals that the Partitions made me hike after? I like stuff that works every time and I like it best if the possible single point of failure is my shot placement and/or error, not whether or not a projectile may mis-perform and I'm willing to pay a buck a piece for projectiles that work, sometimes more.

Everything's a compromise but I don't get on an airplane with a .30-30 and an air rifle and a single shot shotgun with a Damascus twist barrel and 2.5" 12 bore chamber, although I could. Some people in history hunted warthogs with spears, I like a .375 or better with GS projectiles. Call me nutty, if you will, won't hurt my feelings.

native said...

Well Albert,
From my personal experience (and for myself) I have always been a believer in "Big Arrows with Heavy Draw Weight" and "Big Guns along with Heavy Bullets".

If only for the simple fact that I have never been a super shooter!
Some days I am right on and can drive tacks, then other days I just can't seem to hit the broad side of the proverbial barn.

A heavy piece of equipment seemed to be best in the way of insurance to make sure that the tracking was kept down to a minimum, and ( to a certain extent) no matter how poor my projectile placement was.

The State of Cali. has made sure that we use only 30 caliber or larger on big game by making it a mandatory requirement.
And by also placing restrictions on minimum bullet weight and broad head size, and draw weight as well as arrow grain weight, and how large the open upon impact broad head types must fully open up to.

My set up was a finger drawn (large brace height) 100lb. draw weight Hoyt Pro Vantage along with large,and fixed broad heads.
Total arrow weight was never less than 500 grains (if memory serves me right) because I have a long draw length and never used an over draw system.

All of my big game rifles are never under 30 caliber and bullet weights are never under 150 grains with most all at 180.

Some people seem to prefer a smaller bullet (95 to 115 grains) because of meat damage from the larger ones, along with the flatter trajectory that comes with the lighter bullets and arrows.

For myself, I did not like the lighter bullet or shorter lighter arrows.
Too many variables such as high cross winds being one of them.

So in my long winded way I guess that I am one of those old school guys who believes in dropping an animal where he stands with big artillery, as opposed to two days of tracking, because of using too light of equipment.

Having said all of that, I have seen people who were just simply excellent shots, and would consistently drop animals where they stand with light equipment because of excellent projectile placement.

I however, do not fall into that elite category!

Anonymous said...

For someone like me who is still learning about ballistics this post is very useful.

Albert A Rasch said...

Hey fellows,

Thank you for all the comments.

In a way, a wrote this as a start for discussion, and in another as a way of light heartedly saying, "That 375 is your varmint gun, right?"

Of course I exaggerate a little bit when I say that, but I, like Native, don't consider myself a "marksman" in the field. And even that is a bit misleading.

Even though I can shoot very well offhand, (I practice a lot.) My first shot will always be off of a rest. I've never practiced a shot at moving game nor do I wingshoot. (As Phillip can attest to! Remember Miss Darcy at the Media Day?)So I assiduously avoid those shots.

On the other hand, I've killed a fair number of hogs in the field with nothing more than a Ruger 10/22 and High velocity solids that I modify for proper penetration. Plenty have gone down from my 30/06 with Swift A-Frames. So my preference for the big bores is more along the lines of Tom in so far as "I have them, so I use them, and I like it! And it doesn't hurt that its already bigger than a thirty caliber expanded."

The key point though is one's competency. I read in the sixties about an Eskimo that regularly killed Polar bears with a .22 short by hiding behind a mound, sticking his fist up past the edge, squeaking like a mouse, and shooting the bear in the head when he stuck his nose over the edge. That was his business, that's how he made a living. I know a guy that uses a Savage in .223 and kills every hog he shoots at. But that is part of his job as the "Groundskeeper/Warden/Gamekeeper/Gillie/Guide of the ranch he works at.

If you want to shoot, by all means do so, but be good at it. Take the time to learn to do it well, and be proper, thoughtful, and ethical in your shots.

So...

Uhmmmm, hat .325 is a varmint gun... Right?

Best to all,
Albert

tom said...

My varmint gun is my BFR with the .45-70 wheel in it, not the .450 Marlin wheel as that would be overkill :-)

I took a varmint with it once because it was handy at the time. Expensive way to shoot squirrels though...but proper shot placement saved the meat. Not real sharpshooting as it was only about a 15 yard shot and I had all the time in the world.

Photographic evidence and no, I did not recover the bullet so I have no idea on expansion but it was probably pretty minimal until it hit a tree or rock or something some time after getting supper.

tom said...

Oh, for amusement as to what large bore is:

Truesdell in his tome "The Rifle and It's Development for Big-Game Hunting" lists hunters by caliber and area where they hunted. Long out of print but interesting if you can find a copy.

Truesdell lists only hunters who wrote books or were mentioned in some detail in books of others.

The list of hunters who used Muzzle loading rifles of Large Bore, from 4 to 18 Bore has 32 hunters.

Truesdell lists a total of 17 hunters who used Large Bore Breech Loading rifles from 4 to 16 bore.

Truesdell lists the .577 rifles as Medium Bore and lists four hunters who used the .577s as their primary hunting rifles on DG.

tom said...

Mea Culpa, I just looked and amazon has it listed as new and used so I guess it's back. Interesting book.