I'm sorry, I don't mean to flog a dead horse - please bear with me. . .

I tried to explain to my friend about the difference of hunting with a heavy, slow bullet vs a light, fast bullet, but I'm not happy with how I described it.

I know next to nothing about the subject. Here's what I said:

A heavy, slow bullet is preferred to a fast, small bullet when hunting large game since a heavy, hard cast bullet with a large meplat (how do you pronounce that word? mee-plat, may-plat, may-plate?) will penetrate furthur, causing more damage to the animal deeper into it (possibly through it) for it to bleed out, vs a smaller bullet going faster, explosively expanding on impact with perhaps a rib and doing lots of damage but very shallow, not doing much to the internals.

Bassicly, a big ol' bullet will kill more reliably than a ultra-sonic little bullet.

Am I right? The two cartiges I exampled were a .30-06 and a .45-70


Thanks for clearing this up

I think you got it pretty good. On small game the difference won't be as noticable, EXCEPT that the 45/70 does a lot less damage to the meat. In large game, like rhinos, the 45/70 still penetrates thru and thru, while the 30-06 is less than optimal. As a dangerous game stopper, say riled up brown bears or moose or cows even, the heavy for caliber large meplat round will destroy bone without stopping, deflecting, or destroying itself. OTOH, I know an Alaskan who has killed more than fifty brown bears with a 30-06. I say it isn't a good stopper, but it is still a good killer in the hands of a good shooter.

Not quite sure how this is momentum verses energy? The .30-06 and .45-70 loaded to 1895 pressures both have similar powder charge weights, so similar stored energy level is in those charges. Efficiency of translation of that powder energy into bullet energy will vary some in the two, but I suppose one could make it a sort of broad rule of thumb that when two bullets have the same energy, the one with greater momentum will generally be able to do more damage. There's an assumption in that about all else being equal, which it often is not.

I'll move this to the new ballistics forum for others to pick up on.

Interesting...we talk about momentum and energy as if they are as real as our next door neighbor. They are abstract mathematical constructs that conform to the behavior of matter...like shadows cast on walls.

A 45-70 hole in an elk from a 400 grain bullet is not abstract at all...it is the direct result of a big bullet making a big hole.

Same w/ a 308 hole. Dead is dead as well.

We argue about these mathematical constructs, but it's the hunk of metal contacting the vitals that kill, not mv or 1/2mv*v.

That's why are arguments are circular and cannot be resolved..they are only the projections of reality.

ok...one more shot of tequila and to be...

How about you solve the problem all together ? A big bullet, going fast :D Throw that bullet from the .45-70 in a .458 Win Mag or .458 Lott and push it to .30-06 velocities. Problem solved :)

and don't forget that you actually could load the 0-6 with some very good hard ( or strong ) bullets that would do about the same job....I personally think that bullet design and construction are to a great extent MORE important than diameter (caliber) or speed-velocity .... witness the little old 7x57, loaded with proper bullets for the job at hand, will (and has) killed elephants dead..... Jack O'Connor took everything on the North American Continent with the .270 ..... I will grant you this much : a big bullet makes big leaks....a big bullet also "Thumps" harder .... I am a believer in Taylor's Knockout Theory .... bigger and heavier is better as a rule IMHO, until you got to the ridiculous point... wherever that is.... ;)

P.S. Tang...methinks you are in need of a .460 Weatherby ... :D

How about you solve the problem all together ? A big bullet, going fast :D Throw that bullet from the .45-70 in a .458 Win Mag or .458 Lott and push it to .30-06 velocities. Problem solved :)

Ah, but bullets that perform very well in the .45-70 can come apart at higher velocities and perform poorly from faster cartridges. Bullet construction and fluid mechanics have more to do with terminal performance than some of the Newtonian equations. (But I do like big FAST bullets. ;) )

http://www.rathcoombe.net/sci-tech/ballistics/wounding.html

Interesting...we talk about momentum and energy as if they are as real as our next door neighbor. They are abstract mathematical constructs that conform to the behavior of matter...like shadows cast on walls. . .

No more or less so than that the linguistic construct describing the person living in the adjacent dwelling as the "next door neighbor" conforms to the existence of that person and casts a shadow of that person in the imagination whenever we speak the words. AFAIK, the ultimate usefulness of constructs of any kind is unaffected by recognizing them for what they are. If we want to analyze or predict or compare bullet behaviors, it would seem to me prudent to continue using the established system of physics. The alternative would be the rather impractical and daunting task of creating a whole new one. Either that or we make one cartridge using every possible kind of bullet and fire it at every possible velocity and see what they do? That might be more fun. :D

hmmmm.... I'm not entirely sure that I really understood all I know about what I just read of your last post .... and I'm not sure I'm gonna live that long Nick ... ;)

I have this discussion at least once a year with someone. I always use the .22-250 to .45-70 comparison. Both have near the same energy, one with a 50 gr. bullet at 3800 fps, the other with a 405 gr. bullet at 1350 fps (Trapdoor load). Both give roughly the same energy at 1605 and 1639 ft-lbs respectively.
Which rifle do you want in your hands when old Griz decides you are on his lunch menu?
That usually settles it with very little arguing because regardless of where you "think" you stand on the issue, one knows intuitively which rifle is going to yield the better outcome (for you, not the bear!).

Well, that trapdoor load has almost 2.9 times more momentum than the .22-250 load. So it seems to follow my rule of thumb that when two bullets have the same energy the one with more momentum will usually have more damage potential.

Seems this discussion devolves to big bullet verses small bullet. With handguns a 45 caliber bullet makes a hole big enough that the lesser calibers aspire to create, and the 45 didn't expand.
I'd be hard pressed to choose between a 45-70, 444 Marlin or a 405 Winchester to hunt the world with using cast bullets or jacketed. I'd not attempt rhino, elephants with these calibers, most everything else would be open. My 375 Whelen would fall into those chosen but I've not go a lever action in that caliber, yet.

Jim

I have related this story as my best experience on the high velocity light bullet vs the slower heavier bullet:



Was on a dove hunt in TX last October. Mid day others wanted a nap, but me and a another hunter decided to skip the nap and set-up for hogs over a water hole during the mid-day.

We had a group of 20 trying to get in - Had shot 2 of them the first time they tried. About 90 minutes later they started to come in again but stopped short. All but one turned arround and when away. The one came in. My buddy whispered for us to both shoot on his count to 3. He counted - he shot - My safety was on http://www.marlinowners.com/forums/Smileys/classic/angry.gif

When he shot, I could not tell he even hit it with the 7-08 Ruger and 140 bullet - No jump, no squeal, just started to turn and walk away. I got my safety off, shot it, KNOCKED IT DOWN and it did not get up. When we collected our hogs we found 2 good shots had hit that hog within 2" of each other and both exited. His shot was good and would have killed the hog w/o mine, however we would have had to do some trailing.

PS: I hit it with twice the bullet! - A 286 Nosler Partition from a 9,3x62!

Sorry Ray, but, maybe it knocked the hog down because it was the second good shot. I've seen that happen with two shots from the same gun. First has little effect, second acts like the hammer of Thor.

I do hope that everyone understands that no bullet that can be shot from a shoulder held gun can knock over an animal like a linebacker would. The laws of physics are actual laws, and, unfortunately there are way too many variables in all these very limited sample, anecdotal stories.

Now, no one can dispute the power of an appropriately constructed, large caliber, heavy bullet for killing large game animals. No dispute.

No one will dispute the potential for well constructed bullets of suitable caliber driven at high velocity to produce spectacular results. No dispute.

If I had to stop an attack from a dangerous animal, I would prefer the heavy, large, slower bullet. If I had to shoot an animal at over 250 yards under any normal hunting conditions, I would prefer a smaller, faster bullet.

Momentum and kinetic energy, and bullet weight and construction, as well as bullet diameter and deformation all contribute in very complex ways to the ability to humanely kill a game animal. But no bullet has what a physicist would call "knock down power".

I once saw a fellow demonstrating hard body armor shot point blank with a .308 while standing on one foot. He never lost his balance. So you are correct about the bullet momentum not directly knocking game much larger than a rabbit over. I think knock down is generally credited to nerves triggering muscles to contract. Sometimes an animal seems to be knocked down, and other times it just drops like a sack of flour that fell off the back of a truck. Sometimes it stands there or walks a few steps like it is in shock or denial before it falls over. Other times it bolts before collapsing. All results from good hits.

I think the interest is more in how fast the stop occurs. Faster is considered more humane. Shot placement first, bullet power second is the general rule I was taught. No doubt the flatter shooters are easier to get good placement with at long ranges, so choosing the best bullet for the job is not always as simple as picking the one that has the most effective terminal ballistics.

and don't forget the percentage of adrenalin the animal is carrying at that particular instant the bullet hits it.....

we do a good job of using a reasonably sized, reasonably heavy bullet, going at a reasonable speed, and place it in a reasonable place, and every once in a while, the completely unexpected happens, the animal runs off like we didn't even hit it ! ..... killing is not an exact science, and no matter how we try to compartmentalize it, strange things still happen fairly frequently..... in over 50 years of hunting, it still never ceases to amaze me......

No more or less so than that the linguistic construct describing the person living in the adjacent dwelling as the "next door neighbor" conforms to the existence of that person and casts a shadow of that person in the imagination whenever we speak the words. AFAIK, the ultimate usefulness of constructs of any kind is unaffected by recognizing them for what they are. If we want to analyze or predict or compare bullet behaviors, it would seem to me prudent to continue using the established system of physics. The alternative would be the rather impractical and daunting task of creating a whole new one. Either that or we make one cartridge using every possible kind of bullet and fire it at every possible velocity and see what they do? That might be more fun. :D

That physics is great...got us to the moon and back. BUT, I'd argue there are many more variables involved in predicting precisely how a bullet will behave upon entering a critter.

Bigger is better, faster may be better, too. How big is big enough?...depends on those variables. A 22LR might do the trick w/ energy to spare.

I'll always take my chances with things that seem in the overkill category. Better to have too much gun, than not enough gun.

Say you are out deer hunting, but in the waiting a giant trophy 7x7 Elk walks out at 250 yards and you are standing there with your trusty .243. Wouldn't you feel more confident if you had a .300 Mag ?

This argument is like Lambchop's show ending song. This is the one that will never end, it just goes on and on my friends.

yep, in this one, I have to agree with Elmer, "Too much gun always beats the alternative" .....

Sorry Ray, but, maybe it knocked the hog down because it was the second good shot. I've seen that happen with two shots from the same gun. First has little effect, second acts like the hammer of Thor.
.....

Well OK...But that 9,3x62 has knocked over everything else I've shot with it, too!

I'll always take my chances with things that seem in the overkill category. Better to have too much gun, than not enough gun.

Say you are out deer hunting, but in the waiting a giant trophy 7x7 Elk walks out at 250 yards and you are standing there with your trusty .243. Wouldn't you feel more confident if you had a .300 Mag ?

This argument is like Lambchop's show ending song. This is the one that will never end, it just goes on and on my friends.

Well, if I had the elk tag in my pack, I would be carrying the .300 for sure. If I had no elk tag, and a .243 was my deer rifle, I'd be carrying the .243.

While you are better off with too much gun than with too little, there is no advantage to too much gun over perfectly adequate guns. THAT concept is something I have come to believe after many years of watching things shot with many different calibers in many different situations. It is the only argument I have with large, powerful rifles. I just don't see any advantage over "adequate" rifles.

Now, my views on what is adequate have also changed with all that time. By adequate, I now mean "able to take any reasonable shot at any reasonable range and expect a humane kill from a reasonably good shot". That means I do not consider the .243 adequate for all deer hunting any more. On the other hand, nothing "bigger" than a .30-06 is needed on deer, ever.

The other part of my opinion stems from the fact that I just don't enjoy recoil, so I don't want to absorb any more than I must to provide the power necessary. That's why I own a .300 Win. I think it is the smallest round that is completely adequate for anything that walks N.A. I'm just not interested in Kodiak Brown Bears, so it fits my completely adequate criteria just fine.

I also think that the vast majority of shooters are better shots with lighter recoiling rifles. Some can learn to ignore recoil, but it takes a lot of shooting to do so, and constant practice to stay on top of recoil effects.

So if you want to get kicked, that's OK with me. We won't go into the possible pathology of masochism at all ;) but I think it is important to any newer hunters to understand that there is "what is necessary", and then there is what is just "doing it for the fun of it".

Sask I do agree with you 100%. I do enjoy the recoilers, and yes, it does take practice for me to keep a flinch down. As Bob once said, it is a great feeling to be able to make a hard kicking rifle, shoot tiny groups.

As far as "adequate". For deer, I would take a 7mm-08 if that's all I was going to pursue. But I do have plans to take Elk and Bear as well. Maybe I'll never make it to Kodiak Island, but I would love to. I would never reccomend a new shooter to grab up a magnum anything. I tell new shooters to start with a .22 LR, then move up to a .223 or .22-250, or MAYBE a .243 or .257 Bobby. I don't push my insanity on anyone...lol


I've been at this for years. Since I was about 10, I've been shooting thing's bigger than people thought I should be, but it was a joy to me ! :D

I'm with Saskshooter as well. I used to use a .35 Remington (200gr) for a long time, it was perfectly adequate for my whitetail hunting, then I wanted a 'real' gun and got a .30-06 and used it a long time with 180gr and later 150gr to lessen recoil. It didn't kill the deer any deader and I actually didn't shoot any further than I did with the .35. In an effort to preserve range (because I did start hunting fields more) but dropping recoil, I got a .270 Winchester and used it for a few years with 130gr. Recently, I'm now down to a .260 Remington, which I expect I'll use from now on (unless my wife is going with me and she can use the .260) because it's fine for whitetails and hogs (140gr bullet for penetration). I still have my .30-06 and two .270s and I intend to use the .30-06 for elk soon if I'm lucky enough to go on a hunt (180gr Partitions should do the trick nicely at the ranges I expect to shoot). If I ever go further up north for bear (unlikely, hunting bear hasn't ever interested me) or moose, I'll very likely go with a medium bore like a .338 or .35/.350, not sure which right now, but the .338 Winchester Magnum probably fits the bill fine (for the 250gr Partitions, the short action .338s like the Federal and Marlin Express don't seem to be able to use the 225gr or 250gr without losing powder, the .358 Winchester, while looking very nice from other posters here, seems to haev similar issues with weights that give SD in the .300+ range), although I'm not eager to feel that on my shoulder ;) Alternatively, a .35 Whelen or .350 Remington Magnum with heavy bullets (250gr+) but those will kick as well. I'm not a big recoil person, either :) So, I'll probably just not hunt moose or bear :p

Shane,

Your progression logically graduates you to the .243. Lots of deer have been taken with it, and wives and youngsters like it just fine.

Yes it does, and I considered it when I was getting my .260 recently. The only real issue is that I also want it for a hogs so I wanted a bullet with fairly high SD and the 140gr .260 has good SD. And, it's just me being wierd, but .243 is just a touch too small for me. I know the .243 kills just fine and I know several people who use them with good results, but I'm just not ready to go there yet :)

I will suggest that in my experience, neither momentum nor kinetic energy predicts how quickly a critter gets knocked down. Seen too many contradictory examples - of either - to use them to predict big-game taking abilities.

You and Leverite are both spot on about that. There certainly have been lots of knockdown formulas published that have garnered both supporters and detractors, and none of them works consistently as far as I know? But if you want to determine how well a bullet will penetrate a barrier, or how far it will be blown off course, or how it will behave in nice consistent ballistic gelatin, you can make predictions that work out pretty well. Then you get to decide for yourself how much those results really matter to your purposes? For hunting and self-defense, I am confident a .50 BMG will be rated highly by any knockdown formula ever devised and that it can pretty well back that up, but I wouldn't want to have to carry one on a safari or make a snap shot with it.

Great thread. Very well written posts (a couple almost poetic).
OK. I've read them all. I'm no nearer an understanding of the difference between momentum and energy as applied to bullets than I was when I started. I understand that they are often confused, one for the other.
More info or a link, please.
Thanks,
Pete

Pete
Energy can be potenial to do work or actual work being done. Momentum is the work that energy does.
The gun powder stores energy (potential) and is released by the primer going off, imparting potenial energy to the bullet. The momentum of the bullet is worked on by air resistance and gravity, reducing the momentum slowly, relatively.
When the energy is used up the momentum is gone.

Jim

Great thread. Very well written posts (a couple almost poetic).
OK. I've read them all. I'm no nearer an understanding of the difference between momentum and energy as applied to bullets than I was when I started. I understand that they are often confused, one for the other.
More info or a link, please.
Thanks,
Pete

Momentum is mass times velocity.

Kinetic Energy is one half the mass, times velocity squared. Neither "applies" to bullets, specifically. They are just physical properties.... basic Newtonian physics.... which have long been claimed to predict various wounding / incapacitation theories.

Very crudely, kinetic energy is closely related to wound channel volume. Momentum is more closely related to wound channel length. Kinetic energy is "shock and awe"; momentum is penetration. Very roughly.

Mass is very important in calculating momentum; velocity is critical in calculating kinetic energy.

The truth is that both are required to produce lethal wounds, and there are arguments to be made in favor of either as the most important factor in "killing power" of a cartridge.

An arrow has a lot of momentum, but little kinetic energy, so it needs to kill by cutting. It uses its momentum to get penetration and its sharp broadhead to sever arteries and veins to produce bleeding and death.

A bullet uses its momentum to penetrate tissue, but does not cut at all. If it is properly constructed (expanding) it will transfer its kinetic energy to the tissue it penetrates and create a wound channel larger than its diameter through a very complex set of physical reactions that include hydrodynamic shock effects, and the bullet's own controlled destruction. That wound channel will disrupt organ function, and create bleeding and death.

Solid bullets tend to transfer little kinetic energy to the surrounding tissues, but use their momentum to penetrate deeply creating a long, very thin wound channel. Expanding bullets are able to cause much larger wound channels using their kinetic energy, and kill more quickly because of that wound channel volume.

something else to consider :

the rotational "speed" of the bullet.... the faster (higher velocity) the bullet goes, the faster it rotates, and I believe that the more the tip comes apart when - slightly after, it hits the animal. this can be pictured as the teeth coming off a circular saw blade thats spinning ....producing (sometimes) the "that thing looked like it swallered a grenade" effect. this happens frequently with varmint bullets, less so with the hunting bullet. I believe that if you get a "regular" or "standard" style of hunting bullet going faster than it was really designed for, this efffect can be achieved with some regularity ..... what do you think ??

I think the bullets hitting with more energy than they were designed for can cause them to more like shatter as opposed to a controlled mushroom. I think this is what some folks with .243s see with close range shots and some bullets, particularly when the bullet hits a bone but the same bullets at further range, even hitting a bone, perform quite well (the bullet has had time to slow down and bleed some of that energy off by the time it hits so it doesn't fragment as bad). I've also heard similar results, but the opposite, for 7mm-08. The theory I heard is that since the 7mm RM is so popular (and has been for so long), 7mm bullets are designed more for those energies and the 7mm-08 basically behaves like a down-range 7mm RM. Sometimes the bullets don't expand as well as you'd expect they should even at closer ranges with the 7mm-08. I've never used any 7mm, so I dunno if any of that is true or even close to true... I just like to read stuff :)

yep Shane, thats what it looks like to me also, the tip-front third shatters and spits out in kind of a circular pattern, shedding pieces as it goes, makes one whale of a wound channnel....

OK we are getting back into claims that either method of measurement will predict performance in the field. Folks, that just isn't true. Oh and get it out of your heads that bullet expansion is required. Sometimes it is helpful and sometimes not.

Here's a nice example that shows how flipping silly all of these formulas and claims are, because it will debunk both sides at the same time.

Saturday my wife shot a good sized pig, let's call it 150 lbs. Estimated as the pieces of the carcass that we took home weighed a bit over 80 lbs (left out the head, guts, hide, and legs below the knee/elbow joint). Anyway, she shot it with a 6mm Rem and a 100 gr. PSP factory load. Let's estimate that the impact velocity was 2800fps with a 100 grain bullet. Kinetic Energy = 1,741 per the Beartooth calculator, and momentum would be (100gr) * (2800fps) = 280,000 grain feet/second (divide by 7000 to get this in the usual pound/feet-sec units but it doesn't matter as the units in this example will be the same).

Pig died on the spot. Except for some spastic kicking, it did not move.

Case #2:

A few years ago I shot a pig with a handload of a 400gr. Speer bullet in a .458 Win Mag at a measured 2,150fps muzzle velocity. Impact velocity on a small pig was estimated at perhaps 1,800fps, for a KE of 2878 and momentum of (400gr) * 1800fps, or 720,000, same units as above.

With nearly twice the kinetic energy, and between 2 and 3 times the momentum, do you know what that pig did? It rolled over, got up, and ran off, much to my complete astonishment. Oh and guess what, it weighed in the neighborhood of about half what the one my wife shot Saturday.

RAN OFF! Now, granted, it was an easy blood trail... appeared to have been made with a paint roller for about 50 or 60 yards, with chunks of internal organs mixed in.

But the darn thing ran off. And no, my wife did not hit the brain or spine when she shot hers. Both animals had chest cavity wounds.

Anyway when the people who believe in formulas can explain that one, I'll be all ears.

The obvious answer is that Elmer Keith < Jack O'Connor ;)

It's easy Mike, it means we should hunt Grizzly with a 6mm :D

The obvious answer is that Elmer Keith < Jack O'Connor ;)


.270 Jack was nothing more than a blow-hard glory hound, who happened to be lucky. He had no compasion for the animals he totured to death using that sub-standard rifle.

Easy, big fella!

The point of my post was that every single "formula," "theory," or whatever you want to call them would have predicted the exact opposite. Every formula out there rewards either kinetic energy, momentum, bullet mass, bullet diameter, or some combination of all of the above, as being "better" for hunting.

My take on the various formulas is that they mostly were invented by gunwriters who simply derived a set of numbers that matched their own preconceived notions of what hunters should already be using.

In other words, they are just mostly made up and can't be relied on to predict much of anything.

Easy, big fella!

The point of my post was that every single "formula," "theory," or whatever you want to call them would have predicted the exact opposite. Every formula out there rewards either kinetic energy, momentum, bullet mass, bullet diameter, or some combination of all of the above, as being "better" for hunting.

My take on the various formulas is that they mostly were invented by gunwriters who simply derived a set of numbers that matched their own preconceived notions of what hunters should already be using.

In other words, they are just mostly made up and can't be relied on to predict much of anything.


I think the most simple answer Mike, is just use common sense. Anybody with enough IQ to be shooting a gun, should be able to judge how much gun they need for any given animal.

I've seen a deer hit by a car...huge momentum and big energy transfer...likely higher than from a 50 BMG hit (sorry, haven't done the calc).

Deer survived and ran off. So, these abstract numbers don't tell the whole story.

IMHO, bullet performance is more important than any other factor. A lighter bullet that can be counted on to perform...e.g. Barnes TSX, Nosler Partition, etc. can kill more surely than the heavier, FMJ bullet at an equal or higher velocity that has more momentum and more energy.

DOn't we all really know what works and what doesn't? Why dwell on these numbers other than for predicting bullet trajectories.

While it is absolutely true that the numbers are not the whole story, you can't ignore them because it is, in fact, momentum and kinetic energy that make it possible for bullets to kill anything. The problems of numbers not matching results is not in the physics; the problems come from all the other variables that exist in real life hunting. The energy the bullet carries must be translated into tissue damage of some lethal sort, and that process is very complex. Any attempt to make it simple by just looking at the numbers will fail.

I absolutely pay attention to the numbers, but I do not base any decisions about what to use based solely on any specific numbers. I read ballistics charts and everything I can on terminal ballistics of hunting rounds, and I carefully examine every animal I shoot to see the effects.

Years of that have created the opinionated *** you're reading now. ;)

The abstract numbers do not tell the whole story, but they are an essential part of the story, and understanding each part is the only way to get the whole picture.

The problems of numbers not matching results is not in the physics; the problems come from all the other variables that exist in real life hunting.

Let me take this one part of your post and expound on it a bit. When we get results that are opposite of what the "numbers" would suggest, does that not imply that the "other variables" are (by far) the most significant part of the equation?

I will agree that the numbers are in fact very handy for predicting trajectories... that is one thing they do very, very well. But for predicting game taking ability, they are loose correlation, at best, with so much overlap between the extremes that we fool ourselves into thinking that we can make exact predictions.

Believe me I used to get all wound up about various formulas, till I saw a few really squirrely results from the field.

I think the most simple answer Mike, is just use common sense. Anybody with enough IQ to be shooting a gun, should be able to judge how much gun they need for any given animal.

Ah, you'd think that, but when people get very contradictory (and sometimes very bad advise) from the mainstream shooting press, it's a wonder things turn out as well as they do. Face it - cartridge development could have stopped 100+ years ago, and it wouldn't hinder our results in the field much at all. I generally hunt with a .35 Rem (1906 introduction) and could do very well with anything invented around the same time, or before, the .30-06. That's a hundred years of trying to think of reasons for new guns and cartridges! With that in mind it sort of explains (to me) why the gun press is so full of B.S., by and large. They simply haven't had much "real" news to report in the interim, save for better and more reliable optics, non-corrosive primers, compound bows, and handgun hunting (where legal). And maybe stainless steel guns... and a few bullet types (Nosler, Barnes, european equivalents, etc.). I'm sure there are a few other things I have missed but you get the idea. Oh, for shotgunners, how about one-piece plastic wads, and screw-in choke tubes......

You gotta admit it's a tough job to stretch a paragraph's worth of content for a century!!! :D

This has been an interesting thread, but I confess, I've must have seen it a hundred times on various boards and often multiple times on the same board.

We've been hunting deer for so many years in the US that we have acquired a lot of great info about cartridges. I do know a couple of things: 1) people tend to shoot more accurately with lighter recoil rrifles - maybe that's why the .243 does so well despite the fact that it is "inadequate" for deer. 2) ballistics can be useful, but they don't tell the whole story - 30-30 and 35 Remington case in point. They've been taking thousands of deer year after year. 3) large, heavy for caliber, non-expanding, flat point, wide meplat bullets impacting in the neighborhood of 1500 fps penetrate beyond all paper expectations and create a larger wound channel than their diameter would suggest. - same bullets can also damage less meat.

It mostly means that we have many choices of excellent rifles and calibers despite the technical issues we tend to argue over.

Have a great one fellas!

Finn Aagaard > (Elmer Keith + Jack O'Connor) :D

Let me take this one part of your post and expound on it a bit. When we get results that are opposite of what the "numbers" would suggest, does that not imply that the "other variables" are (by far) the most significant part of the equation?

I will agree that the numbers are in fact very handy for predicting trajectories... that is one thing they do very, very well. But for predicting game taking ability, they are loose correlation, at best, with so much overlap between the extremes that we fool ourselves into thinking that we can make exact predictions.

Believe me I used to get all wound up about various formulas, till I saw a few really squirrely results from the field.

I think we mostly agree, but I do think the numbers mean something ... just not what many think they do. Kinetic energy is a good measure of the potential of the round to produce a specific volume of wound channel. The complication is that a specific volume can come from wide and short, or narrow and long, and the factor that determines which of the two it is, will be bullet construction and sectional density. Another complicated factor.

Whether you need wide and short, or narrow and long wound channels depends on the game being shot and the presentation angle. So, even though kinetic energy means something, it must be understood and interpreted while accommodating many more variables.

Two shots from the same gun, with the same "presentation" angle, into two deer of about the same weight, from the same distance, and at the same phase of the moon, will create two different results. But that doesn't mean that we should ignore kinetic energy or momentum in our considerations about what is or what isn't an adequate cartridge for specific game. It just means terminal ballistics is a very complicated field of study.

Lots of people have trouble with complicated ideas, so they try to reduce issues to simple equations about energy. Energy is actually what makes bullets kill, but it is the complicated variables involved in the application of that energy that hunters need to understand.

When we get results that are opposite of what the "numbers" would suggest, does that not imply that the "other variables" are (by far) the most significant part of the equation?

Not necessarily by far the most significant, but significant enough. I agree, though, that the equations we should be using have far more variables than just velocity, bullet diameter, and bullet weight, which is what we always try to simplify the equation to be dependent upon thinking they are the biggest so they are all that really matter. The thing is, lots of those less significant variables can add up sometimes to change the outcome.

In reality, there may be dozens of variables (if not hundreds or even thousands) that have some significance to what happens. A bullet passing through a deer's body is a very complex set of equations... different densities of organs, the boundaries between the organs and what angles they are, bone densities and bone shape with the angle and point of impact by the bullet, etc. if you want to get as exact as you can about it. And that doesn't even include stuff we probably can't even measure, like mental state and what hormones are flowing where, etc.

We try to simplify what happens down to what we think the three biggest variables are (velocity, diameter, and weight) but that can ignore a lot of other less significant variables that can gang up on us and trump one or several of those. We can think about hitting bone vs. passing between the ribs, etc. but it could even come down to things like if the animal is breathing in at the time and has its lungs full of air vs. it having breathed out (air is compressible, fluids aren't, so lungs full of air might mitigate hydrostatic shock more than having a lot less air when breathed out, I have no idea, really, just throwing ideas out).

So, ignoring bullet placement, sometimes velocity, diameter, and bullet weight are enough to overshadow anything else, sometimes it isn't and all those other things can add up to make it look like we were thrown a curve when, really, we just didn't take all the other stuff into account (not saying that we could even possibly take it all into account, just that we didn't). We want the equations to be simple using things that make the most sense because it's easy to understand. The problem is that it isn't simple, so while we try to approximate by using fewer variables, we will end up having these outlier cases where we shoot a small hog with a big gun but it runs away but we shoot a big hog with a small gun and it falls like a sack of dirt and we're left wondering why.

I think we mostly agree, but I do think the numbers mean something ... just not what many think they do. Kinetic energy is a good measure of the potential of the round to produce a specific volume of wound channel. The complication is that a specific volume can come from wide and short, or narrow and long, and the factor that determines which of the two it is, will be bullet construction and sectional density. Another complicated factor.

Whether you need wide and short, or narrow and long wound channels depends on the game being shot and the presentation angle. So, even though kinetic energy means something, it must be understood and interpreted while accommodating many more variables.

Two shots from the same gun, with the same "presentation" angle, into two deer of about the same weight, from the same distance, and at the same phase of the moon, will create two different results. But that doesn't mean that we should ignore kinetic energy or momentum in our considerations about what is or what isn't an adequate cartridge for specific game. It just means terminal ballistics is a very complicated field of study.

Lots of people have trouble with complicated ideas, so they try to reduce issues to simple equations about energy. Energy is actually what makes bullets kill, but it is the complicated variables involved in the application of that energy that hunters need to understand.

There are those ultimate devotees of energy who assert that for optimum performance, the bullet should come to rest against the inside of animal's offside hide, or the energy is wasted!

Pure BS...I'll go further and state that energy doesn't mean squat by itself. A 180 grain FMJ at 2800 fps can drill a small hole clean thru a beast and it will do minimal damage. And a 165 grain Barnes TSX at a slightly higher velocity (but, with the same energy and less momentum) can also pass clean thru the beast and rip the innards apart.

Most all hunting bullets have ample energy to spare to rip guts apart. It's the bullet design that creates the damage.

OK, I will have to very bluntly disagree that kinetic energy has anything to do with wound channel volume. Not only can I disagree, heck I've even got pictures proving that low KE bullets can give very large wound channels..... After shooting a few critters with very low KE handgun loads, the wound channels were not proportionatly smaller to what the higher KE rifle bullets make. In fact there was very little difference at all. Bison, hogs, deer, and whatnot. Handgun hunting can open your eyes a bit to question some of what we've been fed over the years.

Second, bullets do cut tissue, just a heck of a lot faster. It depends to a large degree on the bullet but they do physically cut and displace tissue. Is it exactly the same at the cellular level as an arrow? I don't know but it's got to be somewhat similar. Again, more obvious once one moves from jacketed rifle bullets down to cast handgun bullets. If bullets didn't cut tissue and cause bleeding, how come the critters are full of blood in the chest cavity when I'm gutting them out????? Cast bullets with a blunt nose will cut very clean holes through critters, and sometimes expanding jacketed bullets will too. The difference is that bullets will also cause trauma beyond their diameter evidently by the shock wave traveling ahead of the bullet nose, caused by tissues being compressed.

OK, I think some people are missing the point about the significance of the different variables. Let's look at it another way. If we want to calculate the circumference of a circle, we use the constant pi times the diameter. Let's say that instead of using a tape measure or calipers or whatever, I estimate a circle to be 3" in diameter. Maybe I just eyeball it or maybe I think one of my knuckles is an inch or so and the circle is 3 knuckles across. Anyway I'm pretty sure the diameter is greater than 2" and less than 4."

Now, due to the battery operated calculators and computers we have, I can get a value of pi to a great degree of accuracy. Pulled this off the internet, pi = 3.14159265358979323846 to 20 decimal places.

3.14159265358979323846 * 3" = 9.42477796076937971538."

Wow, now I know the circumference of that circle to twenty decimal places!!! Or do I?

Actually, I don't really know it to more than one significant digit, because one of my measurements wasn't accurate to more than one digit (the estimated 3" diameter), even though my value of pi was presumably quite accurate.

In this example it is no more accurate to say the circumference is 9 inches, vs. 9.42477796076937971538 inches.

In my experience the KE and momentum numbers and the like are about 15 decimal places deep, and nearly irrelevant.

Remember, when you are trying to prove something in the mathematical sense, all it takes is one counter-example to nullify the proof.

The author of every ballistic formula out there has to qualify it and give exceptions and explantions for this, that, and the other when the formula doesn't hold up. They all do! "Oh, it only applies to this bullet or that bullet. The shot angle has to be (this). The bullet can (or can't) strike (fill in the blank). Animal needs to be alert / not alert. Bullets needs to expand X amount (or not at all). Animal should be breathing and / or heart should be on certain part of the cycle. If all that's true then my formula works great and I can prove it's the only one you'll ever need!!!!"

See what I'm getting at? If you have to qualify all the exceptions and real-life examples that don't meet your scenario, then I think that the formula is dealing somewhere between the 10th and 20th decimal places, when we only have the ability to measure roughly to one or two significant digits.

I really do like hearing how the "rules" don't apply to archery because arrow "kill differently." How about we turn that around? When a bullet causes just as much internal bleeding as a broadhead, I'm confident that it will be just as fatal as a low-energy, low-momentum arrow, despite the fact it has way too much KE and momentum?

Hey, I like that.... it's gonna be my new pet ballistic theory! And I'm pretty sure no one can prove to me that bullets that cause as much internal bleeding as an arrow are less fatal....

Over to you :D

Well... what you've demonstrated is that we can't even agree on what we *think* are the most significant variables :) Some think it's velocity, diameter, and bullet weight. Others think those don't matter at all (then what does?) I think it gets back to about the only thing we can agree on... bullet placement is the most important factor.

For anyone who wants to read about it some more.

http://www.chuckhawks.com/energy_transfer.htm

http://en.wikipedia.org/wiki/Hydrostatic_shock

http://www.angelfire.com/art/enchanter/terminal.html

http://rkba.org/research/fackler/wrong.html

I think there is an optimal balance for this - a ship weighing many thousands of tonnes drifting towards you at 1 fps will have ENORMOUS momentum, and an electron traveling near the speed of light will have ENORMOUS kinetic energy, but neither on their own will kill you - there's a happy medium.

Also, empirically derived formulas (ie - derived through experimentation) are extremely complicated. I just finished writing a final exam on thermodynamics (gah i hate thermo!!) and some of the equations are NASTY long, and those are just for convection coefficients, not plotting bullet paths.

Scientists (of any kind) have a tendency to explain things they can understand and ignore things they can't. Thus it is with terminal ballistics --> it gets ignored since it can't be easily explained.

All these posts have a grain of truth to them, and I think we're arguing about something we can't win at.


In the end, all the formulas in the world don't match real experience.

Ok, I think we're getting derailed - the origional question was if I described the difference in performance (and some reasons there of) between a slow, big bullet and a small fast bullet. I think I got my answer.

Thank you all for your replies, but I didn't want this to turn into a big argument. I had assumed this was talked about before and I just missed it, and had no intention on starting a debate (not that those arn't good once in a while ;) )



Recap:

1) More important than either energy or momentum, is shot placement.

2) Energy and momentum are attributes in Newtonian physics, and while they are necessary for bullets to kill game, they are only small peices of the puzzle.

3) Experience shows that unexpected things happen expectantly often.

4) Common sense and experience are better judges of so-called "knock-down power".



Thanks for all the input.

Ok, I think we're getting derailed - the origional question was if I described the difference in performance (and some reasons there of) between a slow, big bullet and a small fast bullet. I think I got my answer.

Thank you all for your replies, but I didn't want this to turn into a big argument. I had assumed this was talked about before and I just missed it, and had no intention on starting a debate (not that those arn't good once in a while ;) )



Recap:

1) More important than either energy or momentum, is shot placement.

2) Energy and momentum are attributes in Newtonian physics, and while they are necessary for bullets to kill game, they are only small peices of the puzzle.

3) Experience shows that unexpected things happen expectantly often.

4) Common sense and experience are better judges of so-called "knock-down power".



Thanks for all the input.

#5...(REALLY #1) Don't waste time or money on crummy bullets.

Not a bad recap..... oh, and yes, we argue about this from time to time! :rolleyes:

The other thing that occurs to me re: the various formulas..... if you go on a deer hunting trip, and shoot several deer with the exact same load / rifle / shot placement, wouldn't the various formulas predict identical results (whether good or bad) since the KE and momentum are the same?

Having said that, I can recall a trip with 3 deer taken, under nearly identical conditions, with the same rifle and load, and big surprise coming up here.... all reacted quite differently to the shot. One DRT, one ran a short ways, and one ran a really long way.....

If there is no consistency in a scenario like that, then I don't know why on earth we'd give the least thought whatsoever to using some formula to compare completely different guns, cartridges, shooters, animals, and circumstances.

Having said that, I can recall a trip with 3 deer taken, under nearly identical conditions, with the same rifle and load, and big surprise coming up here.... all reacted quite differently to the shot. One DRT, one ran a short ways, and one ran a really long way.....

Yep, I bet --> hence #3

Not a bad recap..... oh, and yes, we argue about this from time to time! :rolleyes:

The other thing that occurs to me re: the various formulas..... if you go on a deer hunting trip, and shoot several deer with the exact same load / rifle / shot placement, wouldn't the various formulas predict identical results (whether good or bad) since the KE and momentum are the same?

Having said that, I can recall a trip with 3 deer taken, under nearly identical conditions, with the same rifle and load, and big surprise coming up here.... all reacted quite differently to the shot. One DRT, one ran a short ways, and one ran a really long way.....

If there is no consistency in a scenario like that, then I don't know why on earth we'd give the least thought whatsoever to using some formula to compare completely different guns, cartridges, shooters, animals, and circumstances.

Mike, I've had the same thing happen, or close anyhow, .... I have learned that if I hit a rib going in, (I almost always do Boiler room shots) things come to a quicker halt by far... now all I gotta do is figger out how to always hit that rib.... ;)

Thank you all for your replies, but I didn't want this to turn into a big argument. . .
If you think this was a big argument, you haven't been paying attention. ;)

Let me break ballistics out into its three constituent parts: internal, external, and terminal ballistics. It is pretty impossible to argue against physics as a good predictor for the first two. We see examples of it all the time. You could maybe even argue that the role of momentum in exterior ballistics is so critical to bullet and gun design that the tools needed to achieve good shot placement, the item we all seem to agree is most important, would be more difficult to come by without knowledge of it. In that sense momentum is important to the subsequent terminal ballistic event via delivery precision, but just not nearly as useful in analyzing the terminal ballistic performance itself.

And maybe in the end it is actually possible to create an accurate stopping power formula, but the reason it doesn't seem to be so has more to do with how inconsistently the results data are gathered? If every deer hunter had a stop watch that triggered on first impact and stopped when the game dropped, we would likely be able to find out which rounds worked best for the average hunter to stop deer with at different ranges. We might then derive a stopping formula that would rank the cartridges accurately as a reflection of that data? However, there would be such immense overlapping scatter in the results that the difference would be hard to distinguish over a fairly wide range of ammunition.

Then we have the matter of who the average hunter is? You might need a 4D matrix that additionally ranked hunters by both marksmanship and years of experience? I would expect the data on the better shots would show best results from somewhat heavier rounds than the average shot did best with. That is because the better shots will control the big recoiling guns better. However, you would probably have also to apply an adjustment based on years of experience to compensate for the greater likelihood buck fever in the inexperienced hunter would throw his marksmanship off.

The bottom line would be a formula or at least tables that would let the hunter select a cartridge that gave him some added probability of making the most rapid stops possible for him, but it wouldn't be much more probability than quite a number of other rounds would give him. More importantly, the scatter would mean that the formula or table wasn't much good in any particular instance, even if the rounds it selected did offer some advantage in killing rapidity over an average of, say, 30 or more deer taken.

Multiply bullet diameter times sectional density and momentum and kinetic energy at impact times the shooter's years of experience times his NRA target classification divided by the years difference between his age and 40 or so. Whatever it turned out to be, it wouldn't be pretty.

Very good, Nick. Don't forget you'd need partial differential equations to model bullet expansion vs. deceleration and wound channel volume for expanding bullets. :)

http://en.wikipedia.org/wiki/Partial_differential_equation

Brings back some memories of college math - and not all of them good!!! :eek: :eek:

By the way the bullet I dug out of the pig weighed 68 grains or so (with most of the "crud" boiled / scraped off). Very impressive for busting through 8 or 10 inches of very solid and dense muscle and fat, and an inch or so of bone (gonna ignore the travel through the chest cavity as that was mostly lungs).

There's something to be said for cheap Remington factory ammo! I may load up some Partitions or Triple-shocks for that gun but right now it appears to be a good combination.

By the way the bullet I dug out of the pig weighed 68 grains or so (with most of the "crud" boiled / scraped off). Very impressive for busting through 8 or 10 inches of very solid and dense muscle and fat, and an inch or so of bone (gonna ignore the travel through the chest cavity as that was mostly lungs).

There's something to be said for cheap Remington factory ammo! I may load up some Partitions or Triple-shocks for that gun but right now it appears to be a good combination.

Mike, maybe you should try a .460 Wby Mag with some 500gr Swift A-Frames. Since energy seems so important to some, that should carry enough to flip the piggy end over end like something from a John Woo movie. 7500 ft/lbs of muzzle energy should be adequate for a small pig :D

Heh... as much as that would probably recoil, I'd actually believe it would be true ;)

That's one of the annoying things about movie firearms physics... you see someone shoot someone else and the target goes flying... well... if a firearm could do that, then it would have equivalent recoil and the shooter would probably also go flying! :)

I know a guy who shot some pigs with a .50 BMG single-shot and I think 750gr. Hornady A-Max bullets. He actually hit one too far back and it ran a little ways, fatally wounded though.

If you hit one through the shoulders with that combination, plan to spend some time looking for the pieces, though! :eek:

I know a guy who shot some pigs with a .50 BMG single-shot and I think 750gr. Hornady A-Max bullets. He actually hit one too far back and it ran a little ways, fatally wounded though.

If you hit one through the shoulders with that combination, plan to spend some time looking for the pieces, though! :eek:


That must be how "Bacon Bits" were invented! The stuff you are supposed to sprinkle on a salid?

Now I know of a "justifiable reason" to buy a 50;).

Cheezywan

Mike,

That's one of those things you see mentioned over and over, that bulk Remington bullets perform beyond expectations (based on price). I used to use bulk 165 grain flat base Remington softpoints as a less expensive alternative to 168 grain Sierra MatchKings for offhand and sitting rapid practice. I didn't need to change the load for short range practice, so my setups for the match ammo stayed the same. I don't recall there being any flies on them.

Differential equations will be something Thegrandenigma is more than familiar with if he was taking thermo. They are required to model thermal effusivity, among other things. When I took differential equations, the professor was published in the application of them to social problems. He gave us problems like, if two streams flowing at this and that number of gallons per hour contribute to a reservoir of some volume in gallons and having an evaporation rate of a certain number of gallons per hour with any remaining excess overflowing its dam, and at 2 pm on Monday a plant starts adding a pollutant at some number of gallons an hour to one of the streams, at what day and time will the pollutant concentration reach its equilibrium concentration in the reservoir? I don't recall him posing us any bullet deformation problems, though.

Recap:

1) More important than either energy or momentum, is shot placement.

2) Energy and momentum are attributes in Newtonian physics, and while they are necessary for bullets to kill game, they are only small peices of the puzzle.

3) Experience shows that unexpected things happen expectantly often.

4) Common sense and experience are better judges of so-called "knock-down power".


Thanks for all the input.


tge, There's a possibiliy no one has mentioned yet:

The effect of hydrostatic shock transmitting through the body to the brain!

I remember reading a study of a buff "cull" hunt in Africa. Seems someone got curious about why some of the buffs fell DRT and yet others ran and ran and ran. So, autopsies were performed.

Autopsies reveled that the DRT were either spine shot or heart shot but that a large percentage of the ones that ran were heart shot too???

<O:pThey determined that the DRT heart shot buffs died from brain hemorrhages - Not the heart shot itself. Theory was that the heart was in the pressure pulse of the heart beat when hit facilitating the hydrostatic shock to be transmitted to the brain???

<O:pDon't want to start-up more debate - Just think this theory is interesting and, if true, could apply to other species and thus could explain some of the different reactions when hit!!!<O:p</O:p

Oh great, Ray. Another variable. ;)

Actually that is interesting. I've always heard that getting punched in the chest at the wrong phase of valve operation could kill you, but can't verify it from personal experience. Same with a bullet striking soft body armor over the heart at the exact wrong moment, but I expect that's about heart damage being done in both cases, and not pressurizing the brain. Nonetheless, I don't see why a pressure wave up the carotid artery should be impossible?

How'd you like to have the job of doing the autopsies? "Betty, grab that horn and help me roll 'im over on the table, will you, please?"

Ray there might be something to that. The pig my wife shot, the bullet went through the top of the heart.

I once shot a small pig with a cast bullet reload using a .45 Colt revolver. The bullet punched the bottom of the heart and it just tipped over and started kicking.

Then again I've hit stuff through the heart that ran.

It seems to me that one can ignore most of the math with the use of some "common" (often rather uncommon...) sense and proper bullet placement.

Fatal wounds are the result of permanent effect upon vital organs or organ systems. This can be accomplished with ANY projectile that will cause the above to fail.

I have killed antelope with a .243 and a 300 RUM. The .243 antelope was definately less dead. Both hit the ground before the respective rifle came out of recoil.

I've yet to meet a critter that would openly discuss newtonian physics. Human critters are the only creatures with a preconceived notion of the correct attitude and stance to assume when shot.

Death itself is not subjective. The time it takes for an animal to succumb to fatal injury often is. (non CNS)

The only shot that appears to follow any reliable "hammer of Thor" rules are CNS shots. They work the same every time, regardless of any equations, theories etc.

Hydrostatic shock? Yes. Don't forget fragmentation. Results are quite similar.

I enjoy using various calculators to approximate trajectory etc.

Here's a couple of equations that I have found that work well:

Proper shot placement = death.

CNS shot = instant death.

I am by NO means the most intelligent or experienced member here.

Formulas and equations can predict with boring accuracy the flight path, terminal velocity, energy, momentum etc. ad nauseum.

I have yet to find the "usefullness" of these figures as they relate to flesh and bone, with the exception that they are not bulletproof.

With these formulas, you can without much discussion, know for a fact what is happening during the atmospheric flight portion of a projectile. You won't find any empirical evidence opposite this. Try that for terminal ballistics and the water becomes muddied quite quickly.

Shoot well and let others' arguments be speculative conjecture.

Eric

As I suggested earlier, scatter in results make it difficult to see effectiveness differences through the noise over a fairly broad range. Applying physics to terminal results is therefore always going to give you fuzzy gray as far as predicting any individual event. For dangerous game, it seems to me Jeff Cooper's admonition to use the heaviest round you can control fits the common sense criterion. It would be nice if the math could neatly tell us which heavy is actually "heaviest" in terminal terms? But we aren't even there yet.

I got a tour of a ballistic lab facility that did government contract work. They had a 17,000 fps gun used to simulate meteorite strikes and a 12" bore air cannon used to test aircraft windshields for bird strike resistance, and a number of other interesting toys. The engineer showing me around told me about testing he'd done shooting steel rods into concrete. Up to a certain velocity threshold, it worked well. Higher velocity, however, was less successful. The fast rods would bend in the concrete, with the tip hooking hard enough to turn back on itself and thus fail to penetrate the concrete as far as the slower ones. I want to say that threshold was right around 2500 fps, but it was too long ago to remember.

What is similar to the above is Randy Garrett's description of comparing 500 grain Hornady solids fired at different velocities into wet newspaper (IIRC) at one of the Linebaugh shoots. Hot .45-70 loads out penetrated still hotter .458 Win mag loads with them. Again there seemed to be a maximum velocity threshold for penetration. I have often wondered if that threshold was due to forces attempting to turn the faster slug like the nose of a steel rod fired too fast into concrete, thereby creating a higher drag profile, but I don't know? Since water can compress up to about 5% at that bullet impact force, it may also be some kind of rebound drag increase due to high initial frontal pressure? It would be interesting to model on computer, but would not be a trivial undertaking to get right.

The first time I took a class at Gunsite ('92) I may have seen an example of this in practical application? No way to tell from just one incident, but the example has an unexpected result. Two of Cooper's students had gone hunting Sincerus caffer on the dark continent and brought back and shared the movie. She was shooting a .404 Jeffery. He had a .460 G&A loaded with that same 500 grain Hornady solid mentioned above. She shot a buffalo on an island from standing in a canoe. The recoil actually knocked her out of the boat, though she somehow managed to keep the gun from submerging in the shallow water along with most of the rest of her. Her buff was DRT. His buff took 4 rounds from the .460 G&A to kill, plus a make-sure shot, and had required tracking the wounded beast into thick brush. Much adrenaline was involved in that. He had a closeup shot of one of the Hornady slugs that had hit the buff in the skull and defflected and was was bent the in middle to what appeared to be over 60 degrees.

High velocity ballistics does some odd and unexpected things from time to time, and maximum effective power likewise involves some mysteries.

What is similar to the above is Randy Garrett's description of comparing 500 grain Hornady solids fired at different velocities into wet newspaper (IIRC) at one of the Linebaugh shoots. Hot .45-70 loads out penetrated still hotter .458 Win mag loads with them. Again there seemed to be a maximum velocity threshold for penetration. I have often wondered if that threshold was due to forces attempting to turn the faster slug like the nose of a steel rod fired too fast into concrete, thereby creating a higher drag profile, but I don't know? Since water can compress up to about 5% at that bullet impact force, it may also be some kind of rebound drag increase due to high initial frontal pressure? It would be interesting to model on computer, but would not be a trivial undertaking to get right.


unclenick,
Interesting topic, thank you for sharing your experience.

With regard to Randy Garrett's .45-70 vs .458 test (very impressive)......the .45-70 used a flat nosed hard cast bullet and the .458, a round nosed solid. A flat nose bullet typically penetrates fairly straight whereas a round nose, not so much so. Randy's bullet was also heavier. So, at least in my mind, it was kind of an apples vs oranges test.

Based on some penetration testing I did with heavy bullets in the .30-30 a few years ago, I found that if a cast bullet was hard enough to resist deformation, the higher the velocity (up to the max I could go), the greater the penetration in wet newsprint.

For my tests I used Lyman's 311284 made from w.w.+ 2% tin. I machined a .20" flat on the end of the nose and then heat treated them.
They weighed 220 grs. and, thus, had a sectional density of .33. By comparison a 500 gr. .45 caliber bullet has a .34 s.d.

I placed 48" of wet newsprint @ 50 yards. As it turned out, I should have had a bit more. Pushed by H414, the 220 gr. bullet launched from my 336A Marlin's 24" barrel crossed the chronograph, placed 15' from the muzzle, at 2,043 f.p.s. The bullet had a hardness of 30 b.h.n., and after impact, completely penetrated the 48" stack of wet newsprint and the 1/2" piece of chipboard backing.

At 20 b.h.n. (h.t.w.w. annealed) and the same 2,000 f.p.s.+ velocity, the bullet stopped after 40" of penetration.
Another 20 b.h.n. bullet at a lower 1,626 f.p.s. penetrated less ....35".

Elmer Keith indicated that 2,400 f.p.s. muzzle velocity was ideal for African game......obviously with the properly constructed solid.
He just may be right........................

John

John,

Thanks for that excellent information. It never ceases to amaze me how well the hard cast flat points do.

I am curious if you know for sure that Garrett made the penetration comparison between the solid and the cast bullet at some point, though? Garrett's post in these forums a few years back and the write up on his web site indicate he compared the same solid in both guns.

Very interestingly, if one takes the Hornady 500-grain .458 diameter solid bullet and compares the penetration that results from impact speeds varying from about 1500-fps to 2500-fps, one finds that the higher impact speeds produce the least penetration. When driven to about 1500-fps (as the 45-70 will do) one finds that such solids produce nearly 6-feet of penetration in wet newspapers. When the same bullet is driven to about 2100-fps (as is characteristic of the 458 Winchester Magnum) one finds that the penetration is reduced to about 4 to 4 and 1/2 feet. When one tests the same bullet at 2300-2400 fps (as is characteristic of the 458 Lott) one finds that the penetration comes up nearly 20% short of that produced by the 458 Winchester. And when one tests the same bullet at the blistering speeds characteristic of the mighty 460 Weatherby Magnum, one finds that the penetration achieved is the most shallow produced by the various 458s.

The thing that I wonder about is that the Brits had a century of experience with very large game. They could have stopped at 1800 fps in their stopping rifles, but they didn't.

Bye
Jack

I don't know. Rereading Garrett's information, I have to think that penetrating 4 feet instead of 6 feet is probably adequate in most instances (assuming that represents actual tissue penetration). The other question is how well they penetrate after first breaking through bone? That would subtract some velocity from the bullet up front, though you would expect it also increases deformation. No telling who would come out ahead, then, without trying it out? I believe I read that experiment has been done also at Linebaugh with some rounds, but don't know if the comparison Garrett wrote up was tried that way?

Penetration is essential, but it is not, by a long shot (cute?) the only factor in bullet performance on game. FMJ bullets will penetrate very well, but are seldom suitable for hunting.

One of the main reasons that high velocity can actually decrease penetration is other bullet effects like cavitation and hydrodynamic shock, which are more related to velocity than mass, start to consume the energy (both momentum and kinetic) the bullet contains. Once the bullet has NO momentum or kinetic energy, it is stopped, and both momentum and kinetic energy can be changed into "wounds" of various types. Slow moving bullets produced different kinds of energy transfer to the target, with different types of damage as a result. Less cavitation effect often allows for penetration to increase. Smaller longer holes in things rather than shorter fatter holes results.

The best bullets will be those that produce a balance of penetration, cavitation, and hydrostatic shock that "fits" the game animal being hunted. Elephants need more penetration than white tails, so different bullets will be needed. As animals get as big as elephants, penetration may become the limiting factor for any shoulder fired cartridge, and solids may become the ideal.

On a white tail, one can sacrifice penetration and utilize the "explosive" effects of cavitation and "shock" by allowing the bullet to dissipate momentum and K.E. faster through controlled expansion. The effect can be overwhelming to smaller animals like deer, and chest shots with fast expanding bullets can be devastating. The same approach with elephants doesn't work as well, of course. We can't shoot bullets with enough energy to make devastating chest shots on elephants because the recoil would be too much from shoulder fired guns.

Once saw an experiment on a sandbag perched on a saw horse. Shot with a .30-06 (don't remember the bullet but it was long ago and likely a typical "hunting" bullet) and a broad head tipped arrow from a compound bow. The rifle made the bag "puff up" a bit, some dust escaped, and it penetrated about half way. The effect was quite unimpressive, actually. The arrow completely penetrated the sand bag and almost exited.

Does that prove the .30-06 is less potent as a killer than an arrow? It talks more to the differences in effect of Kinetic Energy and momentum than to "effectivness" on game. Both are completely effective if the nature of the physics involved in their respective performance is understood, and applied correctly.

But in the end, there is no escaping the numbers, and it is not surprising that slower bullets may penetrate farther than high velocity examples in specific tests. Bullets are, in the end, pure physics. It gets very complicated once an expanding bullet enters a living animal, but it is still pure physics, and, if we could ever include all the variables, still understandable in terms of math.

But it is not momentum vs energy at all. Both momentum and kinetic energy are essential for a bullet to work, so it is important to understand both concepts in terms of what creates them, how they affect game animals, which of them are appropriate for the game you are hunting, and how to get those effects from the bullets you are using.

You can have it all, though, at least for critters smaller than elephants. To see a 2" wound channel lengthwise through a deer or pig from a .44 or .45 cal handgun bullet, with the appropriate hard and flat nose will make a believer out of anyone.

So here's a question for those still thinking in terms of energy / momentum "requirements" for harvesting game:

If a 90 lb deer is running through the forest (OK, shot out of a cannon, maybe) at 150 MPH which is a little over 200fps if I did the conversion right, and runs into a 500 grain broadhead that is still and suspended by something insubstantial (such as spiderweb silk), what is the momentum / energy of this collision, and what is the result?

Interesting image in my head right now.

In terms of pure physics, it makes no difference to the outcome whether the deer or the arrow is moving; only their relative motion is important. If the deer hit the arrow at the same velocity that the arrow would have hit the deer, it makes no difference whether you shot the deer, or shot the arrow. Their relative velocity is everything.

We can ignore the fact that both are on the surface of a rotating sphere going about 1000 miles/hour, that the sphere itself is hurtling through space at about 70,000 miles/hour around the sun, and that the solar system is already moving about 140,000 miles/hour around the center of our galaxy. All that matters is the speed of the collision between the arrow and the deer. At least as far as the deer is concerned, and as long as we don't collide with any other celestial bodies going the other way. ;)

Momentum and kinetic energy are all relative, as theories of relativity would suggest.

Yup, correct answer, well at least as far as I know. The reason I brought it up is to point out that there must be a collision for the momentum and KE numbers to have meaning. No collision, no trauma, no dead deer (or whatever). I think that gets overlooked quite often.

We can measure or calculate the KE and momentum, but they are only an artifact of the fact that two bodies collided, whether it be a deer and a bullet (or arrow), or a baseball and bat.

We can probably predict how far the baseball goes when it gets hit by the bat (assuming a solid hit, etc.), but the interesting thing is that we can't predict how far the deer will run when it gets hit. Guess, yes. Bound it, yes (say between 0 and 200 yards on a solid lung hit, probably covers well over 99% of scenarios). But predict it before it happens? No.

Rocky's post #18 in this thread is a great example of how useless KE and momentum are as predictors of incapacitation.

http://www.shootersforum.com/showthread.htm?t=57200&page=2

Take a low-powered cartridge (relatively speaking), shoot at something WAY far away, and see it tip over dead. Throws all the numbers out on their ear when this happens.....

I would still say they are useless in any individual case, but would bet averages over time will show the differences. It's the same data problem that Evan Marshall's studies of incapacitation have: you need a way to isolate the bullet from the shot placement to find out what portion of the effect is due to placement and what is due to the potency of the round? I remember his earliest published data years ago ranked the .44 Magnum below the .357 in stopping power because the few examples he had (maybe just one at the time; I don't recall) featured poor shot placement.

The other night I was watching the History Channel's Ultimate Warrior series. They were comparing the Mafia to the Yakuza in terms of fighting capability. One of the mob tools that came up for comparison was the ice pick. Skinny as it is, a properly placed ice pick driven by nothing greater than elbow grease can produce an instant stop. DRT. If we could work out how to place shots that exactly every time, high rifle power would only be for extending range, not terminal distructive performance beyond anything an ice pick can do.

Hey Nick, why not atttack the problem from another direction, and just simply have the animals grow a solid rib thruout the whole ribcage ? ....the bullets would then all start to expand early on and do their duty .... also, this would prevent some of the sudden movements they would normally make and give us more standing shots....it's win-win... whaddya think ?? ;)

That's actually an interesting point, as I've noticed that a bullet that goes through a shoulder first, usually takes out 3 or 4 ribs. A bullet just going straight into the ribs rarely takes out more than one going in, although I shot a pig through some brush and put a 165gr. Nosler Partition sideways through a pig at short range and took out 2 or 3 on the way in (oval-shaped entrance hole is a pretty good clue that the bullet didn't hit straight on!).

The last pig my wife shot with the little bitty 6mm Rem busted the leg bone, then took out 4 ribs on the way in. Whether it was the bullet or more likely the pieces of the leg bone we don't know.

I once shot a good-sized pig in the shoulder with a .30 180gr. Ballistic Tip. The hole through the rib cage was big enough to stick your fist in, I kid you not! Still that one ran about 75 yards and took an hour to find, while my wife's pig with the 6mm was a DRT.... go figure.... ?

Think bell curve. It all lies somewhere on the bell curve of DRT probability for each round.

That is a good point about the ribs. Or you could shoot a pre-expanded bullet from a 4 bore or some such cannon. It would be interesting to learn if a forensic pathologist could undo the jigsaw puzzle well-enough to tell how much collateral damage is due to spreading the impact out over some bone? It is bound to grow the diameter of the shock wave. Come to think of it, I bet Martin Fackler has done this already. I have a friend who was an early subscriber to his now-defunct Wound Ballistics Review. He might know the answers?

Fifteen years as a Paramedic and married to a deputy coroner for almost 10 years, countless trauma classes, autopsies, and lets not forget the hunting, have proven one important thing: shot placement trumps EVERYTHING.

Muzzle velocity, impact velocity, bullet construction, weight, diameter, all play part in wound ballistics. One can with these factors when known, determine wound channel characteristics. Especially in gelatin. Live flesh and the data is not as reliable.We all know this as the one guy who shot bullet "A" and it failed miserably... Even though we have shot the same bullet same cal. etc. without fail.

If a wound channel leads to or approximates vital organs or organ systems incapacitation AND/OR death will result. Often times the two terms are mutually exclusive and can be the determining factor in "the one that got away", or the one that had to be tracked for ...

If any given projectile has the capacity to disrupt and cease vital fuction it is lethal by definition. There are far to many GIs on foreign shores that validate the lethality of FMJ ammo. I am not saying that this is the ammo we should choose, however, it illustrates the point that shot placement is paramount and "collateral damage" is what it says. Unclenicks' icepick statement holds water. Having seen wounds of this type, there is almost NO damage other than the disruption of the vital system and that collateral damage is insignificant as far as wounds go. (The prisoners around here can be quite hard on each other.)

As hunters, I feel we are obligated to quickly and respectfully terminate our quarry. I would wager that all of us would prefer our animals to be DRT. The behind the shoulder shot is quite questionable in its ability to do this. Incapacitation and death result, however animals hit this way often take their own time to do so.

I have been using a high shoulder shot that has brought tracking and runners to zero. The systems involved in shots such as these bring the shock wave and CNS into play and result in instant incapacitation. I have noticed the collateral damage to the shoulder meat is often significant, but in my opinion, it offsets the possibility of losing the animal entirely. I would gladly give up the shoulder(s) than have the animal expire and feed coyotes.

I believe marksmanship is essential. I spend all year practicing this and honing my skills and handloads to take THE shot. I have weapons that exceed my abilities and I don't aim for a vital "zone". I aim for an exact spot. If I am uncomfortable, I wait until I am or I find another animal. I won't let myself guess or approximate.

The high shoulder shot will usually take out the top of the heart, lung, and one or both shoulders, and often the shock and or high hit will get the spine as well. It is quite effective as far as DRT goes.

Animals are incapacitated or killed by disruption of: plumbing (pulmonary/circulatory systems), control (Central Nervous System), or locomotion. The traditional behind the shoulder shot will take out plumbing. The high shoulder shot will take out the plumbing, control and locomotion all in one. Windage error is increased as the vital zone is extended laterally as well. A little too high and you have spine only. Too low and you have broken the shoulders. Either way, it is a "gear up" and fall down type of shot. Incorperating bone into the hit also ensures the bullet has some expansion.

Just my thoughts. Thanks , Eric

Mike, I've found the same thing to be true .... over the years, I have really tried to just shoot them back of the shoulder, thru the ribs, and if you hit a rib goin' in, they are pretty much not goin' anywhere, and you get a hole out the otherside you can stick your fist in ... this is with "Standard" flatbase Hornaday hunting bullets, usually 165's ....our family-hunting-bunch mostly all shot 0-6's, and I've had the oppurtunity to "autopsy" literally hundreds of deer and quite a few elk that had been taken with basically the same load, as Dad and I loaded for the whole bunch.... I always wished for a bullet that would start to expand a bit better on soft tissue, and still not come unglued if it hit that rib goin' in..... mayhap the answer would have been to use a 25-06 instead of the 30-0 and shoot a lighter bullet like the partitions at a higher velocity..... always wanted a 25-0 ( or a 250-3000 ina good bolt rifle) but never wound up with one ..... and as I've gotten older and more recoil sensitive, I've come to the conclusion that a 6mm will do anything I need done for deer, and have pretty much retired the 0-6 .....

Hydrostatic shock... temporary wound cavitation... projectile preformance.... all this equates to the killing or dead factor of the ammunition in question.

A large, slow bullet will not necessarily deliver more kinetic energy, felt energy or hydrostatic shock than a smaller faster bullet.

We could go into this, but it is extremely variable and math intensive requiring much data to be interjected into the equation.

In SOME cases a larger, heavier bullet will exhibit better qualities than a smaller lighter bullet and vise versa.(I can't believe I used that phrase)

Nosler Partition, A-Frames ect... this type of bullet does well, expanding readily in soft tissue but having a totaly encompassed base that drives the mushroomed frontal section into the vitals of the animal. At least in theory.

If a rid, bone ect. is struck, the frontal section may/may not shear off, but the encompassed rear section, although being of less weight if the shearing occured continues to project into the animal.

I wonder why I could never duplicate this prefomance.

Mike, I've found the same thing to be true .... over the years, I have really tried to just shoot them back of the shoulder, thru the ribs, and if you hit a rib goin' in, they are pretty much not goin' anywhere, and you get a hole out the otherside you can stick your fist in ... this is with "Standard" flatbase Hornaday hunting bullets, usually 165's ....our family-hunting-bunch mostly all shot 0-6's, and I've had the oppurtunity to "autopsy" literally hundreds of deer and quite a few elk that had been taken with basically the same load, as Dad and I loaded for the whole bunch.... I always wished for a bullet that would start to expand a bit better on soft tissue, and still not come unglued if it hit that rib goin' in..... mayhap the answer would have been to use a 25-06 instead of the 30-0 and shoot a lighter bullet like the partitions at a higher velocity..... always wanted a 25-0 ( or a 250-3000 ina good bolt rifle) but never wound up with one ..... and as I've gotten older and more recoil sensitive, I've come to the conclusion that a 6mm will do anything I need done for deer, and have pretty much retired the 0-6 .....

Yup... with our bunch, I've helped clean (literally) 100s of whitetails taken with .35 Rem, .30-30, .30-06, .308, .243, and a few others using PSP, SP, Paritions, and BTs, most of them taken with good ole Remington Green box Core-Lokt SP and PSP. They all do a find job of putting whitetails down. Hopefully this year I'll get to clean a few taken with a .260 :)