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Discussion Starter · #1 ·
Hello, sir.

I have a question concerning an observation that I've seen again and again over the years. I'll ask your views and state mine as well.

As you may remember, in the '60s and '70s, Jeff Cooper and others proposed that the SWC was THE defensive bullet of choice.

Sounded plausible and I cast thousands of H&G #68 bullets for handloading as I was too poor to buy either "store bullets" or factory ammo.

Anyway, doing some informal expansion tests, I began to note that the #68 didn't do all that much more to wetpack than ball and in plastic gallon jugs of water, the effect was rather like ball. These forty-five SWCs impacted at about 1030 ft/sec.

I noted on small game, that this load didn't do any better than ball, mostly on jackrabbits.

I had similar experiences with various SWCs in .357 as well even though driven to much higher velocity.

The one exception: The big 250 gr hardcast .45 Colt SWC whether made by Lyman, H&G, etc.

This bullet, when loaded to about 950 ft/sec caused water jugs to react as though hit with a fast JHP and they showed a better "stopping" effect on varmints.

I suspect, but cannot prove, that this is due to the fact that both the sharp (if hard cast) shoulder and rather large flat nose causes considerably more disruption at right angles than do similarly shaped bullets of smaller diameter, possibly below some critial diameter, and more than the swaged versions as they seldom have sharp edges.

Your views would be appreciated.

Best.
 

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I'm not David, but perhaps he won't mind if I throw in my two cents worth here.
Remember that when Jeff and others advocated SWC's there were NO reliable hollow point handgun bullets available. I tried .45 200 SWC's at 1,000 fps and was underwhelmed on even small animals (one bpbcat in particular).
More recently, high speed X-ray photography has shown that the "cutting shoulder" of the semi-wadcutter only cuts paper targets-- it never touches flesh. The tissue is pushed out of the way by the shock wave in front of the bullet nose. Therefore, all of the damage is done by the flat nose of the bullet, not the so-called cutting shoulder.
This is why the blunt, wide nosed SWC like the one for the .45 Colt does more damage than the H&G68 or similar designs which have a smaller, sharper nose (meplat), for better feeding characteristics.
Back in the 1930's, Charles Askins wrote that the .44/40 was the best stopper of any handgun round available at that time. This was typically a 200 grain flat nose at 950 fps, but with a wide flat meplat.
 

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Discussion Starter · #3 ·
Hello, Mr. Givens. Sure sounds right. I've played quite a bit with high velocity varmint rounds from rifles (another passion) and have seen well-designed JHPs do miraculous, varied things in living tissue, but had never researched out this question.

I sure appreciate your taking the time to respond.

Best.
 
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Stephen,
I think that Tom did a good job of explaining one possible aspect of the history behind the Cols comments.
And this is certainly a very good question, to properly compare the varied shapes and sizes of SWC and other bullet shapes and the permanent wound or crush cavities created in living tissue we need to start at the outside and work our way into and through the cavity.

First, we know that to penetrate the outer layer of the body (the skin) we need a minimum velocity of 191ft/sec. and this action requires an equal amount of energy to penetrating 20cm of muscle tissue.
We can use Journee’s formula to calculate the mathematical equation, 2.13m-kg-cm wherein 2.13 is the energy area.

Using a 158gr lead SMWCHP +P round we know that the round has an average velocity of 884ft/sec from a 4” test barrel upon penetrating the outer skin of the torso we know that the 158gr round will now lose approx. 16% of it’s velocity upon contact with the outer layer of skin as it passes through the epidermis and enters the body.
If we use 742ft/sec as our remaining velocity we can see that the bullet still has sufficient velocity to over penetrate the torso if only muscle tissue is encountered.

To understand why it does not, we need to return to the action of wounding itself; we know that the location wherein the bullet makes contact with tissue will be penetrated given sufficient velocity achieved. This action does not cut the tissue per say or rotate or corkscrew into the body. The bullet causes direct blunt trauma to the contacted tissue in the form of abrasion, quite often the abrasion causes micro tearing of the tissues. This abrasion resembles the form of a ring approximately caliber size around the entrance wound itself. The initial bullet shape that contacts the skin is actually irrelevant as the abrasion ring will be only concentric (round) or eccentric (oblong) depending on the degree of angle to impact with the skin. Thus a sharp edged bullet and a smooth bullet both create an abrasion ring and entrance wound of equal size. This is true of all bullet shapes, the existence of radial tearing or larger micro tearing is caused by velocity not shape. All skin abrades at a uniform rate except for the palm of the hand and the sole of the foot. Skin placed over a hard surface will tear at an increased rate and skin placed over soft tissues will tear at a slower rate. Now that we understand that it is the process of abrasion that cause the initial wound we need to look at the exit wounds into issue to begin to understand why bullets of various shapes lose energy at a faster rate than others.

The exit wound leaving the tissue will be smaller than the entrance wound as the bullet now posses less energy/velocity than it did when it contacted the tissue to form an entrance wound unless the bullet has deformed.
The bullet can deform for several reasons but the first is that the bullet has begun to tumble as it was destabilized over the wound track. The second is that the bullet is of soft construction and the weight of the projectile combined with the resistance to the tissues encountered was greater than the projectiles surface hardness and structural strength.

It is interesting to note that the bullets construction and weight must be sufficiently matched with the surface strength of the materials and the intended velocity of the projectile within the desired rate or range of travel through the wound channel.
The third reason is that the bullet has encountered an existing structure of sufficient hardness to cause either a separation of the bullets construction or a massive deformation of the bullets surface area exceeding the initial diameter, this process of deformation is often referred to as “expansion”.

When the bullet contacts the exterior layer of skin it will begin the process of abrasion once again and due to the decreased velocity and the increased diameter the abrasion ring will separate becoming less visible (in most not all cases) and this will lead to markedly increased micro tearing resembling a star or satellite shape. In some cases if the skin is in contact with a heavy or hard surface it will become abraded in a more uniform manner and display an inverse abrasion ring resulting in the appearance of raw or hanging tissues as in an open wound.

It is often speculated that this appearance is caused by the intense heat of the bullet cauterizing the wound but this in fact a fallacy. At no time is the bullet ever hot enough to sear the tissues encountered as it is easy to note that bacteria and organic materials that were present when the bullet was loaded and fired remain present both in the wound and on the recovered bullet, these bacteria remain both healthy and viable and can be fully cultured from the recovered bullets this is why infection rates are so high in gunshot wounds.

We know that a bullet of equal weight will lose velocity at an increased rate as initial impact velocities are increased. So the shape of the bullet is a secondary factor in wounding to velocity and weight.

Once we have penetrated the skin we know that the bullet begins to stretch the tissues that are contacted, the existence of sharp or prominent edges provide an advantage only when the edges are aligned against the tissues, and this produces a higher rate of micro tearing and cellular compression. The greater the cross sectional diameter of the bullet will increase the radial area of the wound due to the compression of the tissues over the surfaces pronounced edges. In this manner we know that the “ideal” bullet will offer a square or even octagonal impact surface with pronounced edges.
The existence of these edges on all sides will produce a wound equal to and greater than the initial diameter as the bullet continues to yaw and tumble through the tissues.

Wounding not withstanding, we know that our square bullets do not perform well aerodynamically and they would create some interesting feed/functioning challenges.
These challenges can be bridged slightly in the feeding aspect of the revolver allowing the relatively flat shape with the pronounced shoulders or edges to the almost full caliber up to and including the .45 Colt round.
The smaller caliber bullets although they are still consistent with our “sharp” edged desire are effective over a decreasing arc dependent on the size of the projectile.

In auto pistols this advantage is negated by the fact that the bullet must have tapering edges and a shape conducing to reliable feeding/function. We know that as these edges become less pronounced the bullets “shape” advantages decrease rapidly producing a wound that is now only equal to the initial entrance wound/abrasion ring unless the bullet is deformed or begins to tumble.
We know that our bullets will not expand in muscle tissue alone duet o the relatively poor velocity of our handguns and at our given velocities we must now depend upon structural failure whether controlled as in controlled expansion or complete as in total fragmentation.
We know that a uniform controlled expansion to the largest diameter with the greatest number of pronounced or sharp edges is the most advantageous as the bullet will generate a larger wound track all things being equal and this allows the bullet to contact the greatest number of tissues and organs.

*I will editorialize here for a moment, and comment that I do not care to debate the effectiveness of the “light/fast” versus “heavy/slow” nonsense. When I shoot a living creature I have already made the decision to use deadly force and I intend to kill that creature whether it be during a hunt or in defense of my life.

To do this I require my bullet to create a large wound track through as many tissues and organs as possible, this bullet may or may not need to pass through bone structures or intermediary obstacles. Depending on the time allowed and my response times I may only obtain one single opportunity to use my firearm and I am very much opposed to said firearm failing as I currently enjoy being alive and until someone can convince me otherwise that being dead is a “good thing” the idea does not appeal to me.

So please do not respond with theories of hypersonic waves and temporary pulse cavities that will magically damage all surrounding organs and tissues that were stretched for 1/10th of 1 millisecond over a distance equal to 1/25th of the major organ structures of the animal that currently needs to become deceased as quickly as possible. *
End of editorial comments.

I hope that I have answered your question and I hope that the other persons reading this post will think about what I have written and then go out and test their own equipment.
Test to ensure that your ammo does what you believe it will, since neither the gun and marketing press nor the ammo companies can test the ammo on human predators we must all rely on stimulant testing.
You can repeat this testing and you can go hunting, decide for yourselves what you need and work towards that goal.
 

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David has covered the subject well as usual!

I will add just a little to reinforce.

There are some folks who seldom see their name in print but who actually go about shooting a lot of stuff, including cape buffalo, with repeating handguns and they have some interesting things to say.

Their theories seem to confirm what Steve has observed and back up what both Tom and David have explained. They beleive there are 2 parts to handgun bullet effectiveness, given equally good hits:

1. Penetration, your bullet has to reach the intended organ (big surprise). They are not much into expanding bullets but remember they are shooting big stuff.

2. The diameter of the meplat (the "flat") combined with the actual velocity of the bullet through the target organs. Note I did not say the "square of the velocity"... they are not much into kinetic energy.

While we don't need 4 feet of penetration, these guys may be on to something.

BTW, I found out 30 years ago that you could load the 255 gr. Keith bullet sized to .451 in the .45 ACP and it will feed in most of them.

I have actually shot as many of these through a .45 auto as I have the H&G 68.

Carry on,
Jim
 

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Along the same lines, check out the pix at:

http://www.firearmstactical.com/tactica ... cle422.htm

Looks like a Phillips head screwdriver.

From the site:

"The Devel cartridge uses a solid, non-deforming and non-fragmenting bullet
constructed of sintered copper alloy particles. The projectile is
manufactured by Sinterfire Corporation, and the cartridge is loaded for
Devel by Black Hills Ammunition Corporation.

The projectile was designed by Charles Kelsey, and is conceptually based on
the THV brass alloy soft-body-armor-piercing cartridge (Figure 1, inset)
produced in France by Sociiti Frangaise des Munitions (SFM). The unique
concave (reverse) ogive of the THV bullet cleaves soft tissue as it
penetrates, and as these tissues flow across the ogive they accelerate
laterally and are energetically propelled radially outward off the bullet's
shoulder. This action produces a large diameter temporary cavity.

The contours of the Devel projectile consist of a flat asterisk shaped
meplat and a fluted ogive comprised of five convex ridges and five concave
chute-like channels. Ordnance gelatin tests (Figure 3) reveal the dynamic
effects of the concave ogive surfaces produce a large diameter temporary
cavity, approximately 3= - 4 inches, similar the reverse ogive THV bullet."
 
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