Quantifying the effects of large bore handguns

[Prosser]

Let's start with this statement by CraigC:

""I automatically disregard the arguments of those who remain stuck on kinetic energy in a discussion about big bore revolvers. For it is easy to assume that they do not have a true understanding of how these big, heavy bullets work. All it takes is five minutes looking at ballistics tables to understand that if the lowly 45Colt blackpowder load consisting of a 255gr cast bullet at 900fps and producing a measly 450ft-lb's of energy will kill any deer that walks just as dead as a 165gr .30-06 with vastly higher energy figures, then maybe something else is at work other than energy. Which, as I stated, is FAR too dependent upon velocity. Something which the big sixgun does NOT have an abundance of."

I've wondered about a way to quantify the effect of big bore revolvers. It seems that what ever the effect, it seems to accelerate geometrically in caliber from .40" up. The .475, 500's and .510s seem to kill WAY more effectively then they should. Same seems to be true of the .41 and .429.

The best explanation I've heard is the heavy for caliber bullets are longer, and since they yaw and roll as they pass through the target, the increase in bullet diameter and length increases the effectiveness geometrically.
This sort of jives with the increase in a cylinder's external contact surface being geometrically related to increases in diameter and length.

The final factor is the increase in bullet weight has a relationship to speed through the target. The higher the weight, the less it reduces speed as it goes through a liquid medium. This is sort of a reverse measurement of
KE. The heavier bullet penetrates at a higher speed, and maintains that speed through the target. The consequence is the yaw and roll are increased due to the increase in resistance, transfering more energy to the target, and creating a larger wound channel then the caliber might explain.

One other observation:

While I agree with the effectiveness of CraigC's comment/observation, and that combination has always been my idea of the threshold for effective
rounds, the heavier calibers do have serious Kenetic Energy, but it is caused by bullet weight, and this seems to have a geometric effect on energy figures, as does velocity.

Don't really know how to plug the variables into an equation that can factor all of this, and give a comparable value.

Taylors KO theory, though designed for rifles, seems to sort of give reasonable results.

Kind of wish there was something other then the guys on the ranch yelling,

"Damn! That .500JRH hits like a .375 H&H rifle!"

Or:
"We can't explain it, but the 525 grain LFN's at 1100 fps from BuffaloBore
hit and kill like Thor's Hammer!"

What I'm trying to do is build some sort of awareness that there is a HUGE difference between a .429" magnum, and a .510" caliber, even though the actual measurement is tiny.

One other thought.

When you hit a fluid surface you have severe penetration problems as the impact point increases geometrically. In other words penetrating the surface tension/skin of an object with
a needle is far easier then doing so with a .500" bullet. The amount of energy required to break through a surface of fluid increases geometrically as the diameter of the contact area increases.

I suspect deacceleration also increases geometrically as the contact point surface increases. In other words as the surface contact area increases, the amount of force required to get through
the fluid, and maintain speed requires geometrically increasing energy to breach the barrier.

I keep thinking of the sabots designed with tungstun spikes to breach armour fired from cannons. 5000 fps for a spike maybe a 1/2 inc in diameter, or less, that relies on a narrow contact point to breach the barrier,
but a large wound is created by the yaw and roll of the 6" spike once it enters the target.

 

[MikeJackmin]

Imagine a simple test - we want to see which rounds is most effective at killing deer, a .45 Colt, or a .40 S&W. We go visit a convenient venison ranch and are given permission to shoot as many animals as we like. Our plan is to shoot several deer, once each in the chest, and see how much time passes before each deer meets his reward with all four hooves are in the air.

Here's the question: how many deer do you have to shoot before you can have confidence in your results?

Here's part of the answer: some of the deer we shoot are going to get hit on a rib; others will not. Some will be struck in the heart - some will have leg or shoulder bones broken - some will have exit wounds - others will not.

How many important variables are at play? We need to know, and control for each one, or our results will vary by the luck of the draw. Otherwise, if your first group happened to have twice as many heart shots as your second group, the results will be all over the map.

Even if we just limit ourselves to nice clean lung hits, they vary, too. A low hit is much bloodier than a high hit - and sometimes, the skin slides over the entrance wound and covers the hole, while other times it does not. Sometimes a major vessel is ruptured, and other times you mostly just hit air. Sometimes the blood floods the lungs, other times it goes somewhere else. That's just off the top of my head - so how many variables are really at play, even just here?

At the end of a correctly designed test, you'd presumably have your answer. You be able to invite me over, allow me to select either a .40 or a .45 at random, and then use it to shoot the prescribed number of deer. When I was done, you'd be able to look at the results, and correctly guess what caliber gun I had used.

That's a lot of deer.

If this seems improbable, bloody, and difficult, you might reach the same conclusions I have have:

1) It's really, really hard to do a meaningful test - so hard that nobody has ever published one, so

2) We don't really know anything about what the results would look like. Nobody does.

That doesn't have to stop us from guessing, of course. We take the limited data we have, we try to extrapolate from first principles, and we do the best we can. We can explain our guesses in terms of velocity, hydrostatic shock, crush zones, blood and air displacement, neurologic effects, or whatever else we can dream up, but in the end, without real data, it's all just well-intentioned guessing and speculation.

Having said all that, bullet yaw might be an important factor. It might, or might not, work better than bullet expansion, and it might, or might not, travel in something other than a straight line, which might or might not be helpful, too. If I remember right, most bullets tend to tumble in flesh, because the shape that makes them stable in air tends to make them unstable in denser media. Maybe long, thick bullets don't tumble as well as more compact ones? It's possible.

 

[Prosser]

I don't even think it's that simple.

It's more like:

Initial impact effect on nervous system and superficial nerves.
Penetration effect on organs.
Expanding
Hydrodynamic shock,
etc.

I suspect our lack thereof is pretty amazing.

 

[JERRY]

a bowling ball will knock down pin at 27 mph. so will a baseball at 95 mph.

 

[Dr.Rob]

I've seen a pistoloero who is a great shot and handloader spend a whole day tracking: dawn to dusk after shooting and wounding a Russian Boar sow. In the course of the day he shot her SIX different times. Can't imagine a .30-06 at the same distance failing to reach the vitals.

No ONE anecdote is true for all situations of course.

Know your limitations with any caliber and platform. Sometimes your 'Hammer of Thor' is a mild annoyance to live game.

 

[Hammerdown77]

One thing I've seen in reports from penetration tests at Linebaugh seminars is that one cast bullet at X velocity might have, say 35" of penetration through wet newspaper, whereas that same bullet going 200 fps FASTER has significantly LESS penetration. These are typically LFN or some other hard cast lead bullet with a big meplat.

The explanation for that is there's a certain velocity for a given projectile at which the material through which the projectile is moving cannot "move out of the way" fast enough. In other words, the resistance to penetration by the projectile in the medium increases dramatically. Think of the analogy of doing a belly flop off the side of the pool, vs. doing a belly flop off a high dive. You might even get nose deformation of the bullet, or mushrooming, which will cause it to penetrate even less.

There's a certain velocity range at which a given bullet design will penetrate most effectively. In big bore handguns, it's often not what you would expect.

I recently bought a 500 JRH. The numbers on paper are impressive at the top end. 440 grainers at 1350 fps and more. But Buffalo Bore and now Grizzly Cartridge Co. make a round that uses that same 440 grain bullet moving at a leisurely 950 fps. All accounts by those who have actually shot large game, including Jack Huntington himself, claim this round penetrates like no other. Seems counter-intuitive, though. Clearly, that's the velocity range in which this bullet can move tissue out of the way very effectively.

 

[336A]

I think a lot of questions can be answered in this excellent article
http://www.beartoothbullets.com/tech_notes/index.htm

It is IMHO that Mr. Stanton is on to something due to the outcome that this hunter achieved here with a load that is in line with what Mr. Stanton was describing. http://www.rugerforum.com/phpBB/viewtopic.php?t=69822&highlight=magnum

 

[Prosser]

Mr. Stanton seems to have come to the same conclusion that the US Military
and Ross Seyfried have evolved to. The .45 Colt load, 260 grain bullet at between 950 and 1200 fps is enough for anything in the 48.

Big hogs and bears might be an argument, but the 45 Colt load was originally designed for warfare where horses where a huge part of the combat situation.

To counter my own discussion:

Dropping an animal in it's tracks maybe better served by a lesser initial impact.
Brings to mind the guys that tree bears, shoot them with a .22 they don't even notice, and let them bleed out. Perhaps the lost elk in the hunt link might be due to the 30-06 getting the adrenal gland pumping, and or the brain going into
fright-flight reflex. I've heard deer go 100 yards without a heart, after getting nailed by a well placed 30-06 bullet.

1350 fps seems to be the magic number for the hog boys on another forum.
With big bullets the impact and resistance do create a mushroom effect on the big bullets, limiting penetration. One wonders if with a 425 grain bullet at 1350 fps that isn't a good thing?

Somewhere I have a letter from John Linebaugh where he was using a Mountain gun in .45 Colt for a food gun, as was his wife.

They used 260 grain Keith style cast bullets at 1100-1200 fps and they just worked on deer, or anything else.

Last time I talked to him he had moved back to Wyoming, as have bears.
He was thinking about building a light, .338 OKH, IIRC for a carry gun.

 

[Prosser]

The numbers on paper are impressive at the top end. 440 grainers at 1350 fps and more. But Buffalo Bore and now Grizzly Cartridge Co. make a round that uses that same 440 grain bullet moving at a leisurely 950 fps. All accounts by those who have actually shot large game, including Jack Huntington himself, claim this round penetrates like no other. Seems counter-intuitive, though. Clearly, that's the velocity range in which this bullet can move tissue out of the way very effectively.

I wonder about this.

look at the results for the .454 Punch bullet at 1600 fps:
http://www.handloads.com/misc/linebaugh.penetration.tests.asp
49 inches.

I think this kind of shoots a hole in the slower velocity better penetration argument.

The reason LFN bullets don't penetrate as well is they deform at velocities
between 1200-1600 fps, to varying degrees. This may not be a bad thing
since with heavy cast bullets a bit of expansion might be nice, since it increases the wound channel.

Here are 425's at 1350 fps shot into a buffalo:


With punch bullets you can shoot them into sand, clean them off, and reload them, pretty much. Watched someone do this with a .500 caliber punch bullet. VERY tough bullet. It's going to smash through any bone, and not deform, hence the deep, straight penetration.

 

[336A]

One of the variables that must be taken into consideration as Mr. Stanton eluded to is the meplat size of the bullet in question. For example, the famous SSK 310gr 44 mag bullet has a long respected history of making big beaties taking permanent dirt naps. The meplat of this bullet is identical to the famous Lyman 429421 Keith bullet.

Those Belt Mountain Punch bullets are nice indeed however they are way to expensive for me. A comparison between the Punch bullets and cast bullets can't be fairly made since they're of vastly different construction.

 

[Prosser]

The argument for cast bullets is they just WORK, period, unless someone screws up the casting.

 

[marcclarke]

http://www.amazon.com/Bullet-Penetr...2907&sr=8-1&keywords=duncan+macpherson+bullet

The equations have been worked out, measurements made, and published.

 

[gamestalker]

An example would be an atelope I shot with a .270 win using a 130 gr. PSP at 3150 fps. I had a perfect kill zone shot that in fact blew the heart to mush, yet the antelope ran for about 500 yds. before stopping and then falling over. The projectile went through and through taking with it most of the heart organ. In other words, that animal was running dead.

GS

 

[AKMtnRunner]

I think there's only so much energy that can be transmitted away from wound channel through tissue. I mean that once the tissue turns to mush, the blast "ripple" loses most of its energy wave. However, with a larger circumference of a big bore, the bullet's energy is spread out more and has a better chance of staying under that mush threshold to send out more blast "ripple".

I wish someone would test terminal ballistics with tiny SACKS of fluid like paintballs. That would be fun.