Shotgun Penetration based on shot size

.22lr

New member
All,
I am not nearly the writer I think myself to be, so please bear with me.

In a recent discussion on whether or not BB sized shot would stop a man effectively, many espoused the use of birdshot for self/home defense. I am NOT interested in stopping power, terminal ballistics, or any tests done with animals. What I am interested in is the belief that adequate penetration in a self defense is not only possible but probable with the smaller shot sizes, namely birdshot, AND that a miss with birdshot will somehow not penetrate building materials and is therefore safer. How do these two seemingly conflicting ideas exist in the same belief?

To reiterate (and hopefully alleviate any confusion the above paragraph may have caused)

1) My question is purely centered around penetration in self defense and building materials.

2) I have trouble with the theory that smaller shot, namely birdshot, will adequately penetrate for self defense, but then not penetrate the relatively flimsy building materials found in most homes (drywall).

3) Though I understand that the tactics used would alter/limit the damage of over penetration, I would ask that the discussion stay centered merely on penetration as it applies to self defense and penetration of common building materials.

4) If it is believed that a shot connecting with the target would have sufficient penetration to stop an assailant and that a missed shot would NOT penetrate building materials, then what are the distances involved? I will attempt to illustrate:
"goodguy>--->"distance X">--->"target">--->"distance Y">--->"wall"

Where the origin of the shot = "goodguy"
The distance from the origin of the shot to the target = "distance X"
The distance from the target to a wall = "distance Y"
The distance from the origin of the shot to a wall = "distance X" + "distance Y"

As this is the first topic I have started I hope that this question is on topic for this sub forum and stated in such a manner as my intentions are clear. If I have violated the theme of this sub forum or have stated my question in such a manner as to cause confusion, I would have no issue with the moderators deleting this post. Thank you all.

VR

Matt
 
.22lr Great Thread Idea Matt

Great Thread Idea Matt

I've been hunting more and reading less this past month, but I read your post this morning and I decided that the birds can wait a while. The only "fly in the ointment" as it were is Suzi my old springer is sitting next to me an rubbing against my leg and whimpering, we'll see how long I can last!

You have produced "I my small mind" a myth buster question. I have a couple of problems with it, so here goes.

1st - You said "I am NOT interested in stopping power, terminal ballistics" I BELIEVE what you are asking is a straight up problem in terminal ballistics and I can not see how to solve for X without it's use.

2nd - I won't get gory, but to be relevant you would need a man and a sheetrock penetration box at the same distance angle etc times 2 to get the right data. Not sure that there will be many volunteers for this.

Here are the things that you might consider;

The tests on sheetrock have been done, over and over. Most jurisdictions have caught a shotgun homicide case and have conducted in one manner or another a sheetrock penetration test with all manner and size shot.

I know I will more that likely hear from Glenn about flawed data , but in general my file folder says #4, #5, #7, #8 shot at 15 ft seems to penetrate 2 to 4 sheets of standard sheetrock. 00 Buck at the same distance seems to penetrate 7 to 9 sheets of standard 1/2" sheetrock. At 30 ft #4, #5 seemed to penetrate 1 sheet of sheetrock, #7 #8 penetrated 0 sheets of sheetrock, and 00 seemed to penetrate 5 to 6 sheets of sheetrock. Our boxes were built as standard interior walls with 4" of air space per sheet of rock shots were fired at right angles to the box. Most of the similar reports concerning this type of test seem to indicate like finds.

Now, that certainly is not a clear cut finding, however, in relationship to the second part of your question, effects against human beings, it is crystal clear!

You Said "What I am interested in is the belief that adequate penetration in a self defense"
This is where the water gets extremely muddy" Let me explain my point;

1st - observations of scattergun wounds on the surface area of the thoracic cavity and extremities of human beings are NOT a reliable way of understanding the morbidity of a victim. Unless you were there at the autopsy (I avoided those at all costs) or read the report and completely understood the details of a shooting scene, you will not be able to truly answer yes or no in most cases. Hits to the head are of course a different animal. So, what we on rare occasions witness may not be necessary reliable or correct when later looked at in a clinical setting.

2nd - Sheetrock fractures at a specific rate of pressure, human beings stop there actions "when ever they do". Some folks fall over at a grazing wound , some even after a heart shot take 30 or more seconds to stop there actions. On the slab at the morgue the classic look at morbidity is a model of penetration and vital organ damage. This is not in dispute, however, in answer to your question "adequate penetration in a self defense" there is more to it, basically how quickly does your enemy "stop his actions", that is why the wild variations of thought on this subject. And not part what you wish to discuss.

3rd - personally, I seek over penetrations of all my defensive rounds. I know that sounds bad!!!!! I kind of chuckle at those folks that believe that they can predict with some kind of accuracy just enough to get to the heart but not enough to go through. My best guess is if it shoots through, it was enough.

My answer to your question is

Where the origin of the shot = "goodguy"
The distance from the origin of the shot to the target = "distance X"
The distance from the target to a wall = "distance Y"
The distance from the origin of the shot to a wall = "distance X" + "distance Y"

with #4 thru #8 and 00 buck if X= 12ft, Y= 2ft, angle of shot at 90degrees, will produce enough penetration to stop a human, and will produce penetration of selected building material.

with #4 thru #8 if X= 12ft, Y= 23 ft, angle of shot at 90degrees, will produce enough penetration to stop a human, and not produce penetration of selected building material.

with 00 buck if X= 12ft, Y= 23ft, angle of shot at 90degrees, will produce enough penetration to stop a human, and will produce penetration of selected building material.
Is that cloudy enough for you?


Well, Suzi is about to chew my new boot laces, so I will close here, it will be intresting this evening to see how many critics jump in. Great thread Matt, it should make some folks think.

Good Luck & Be safe
 
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I think you have two very different issues unless I'm not understanding quite right. One deals with whether there is enough damage to stop a BG. The other is how much damage would occur after penetrating the wall, if it penetrates. The energy used to stop the BG can easily be absorbed by the sheetrock and other wall material. Distance can also matter, as the BG can be closer to you than the wall is, and with lighter shot in particular that can become an important factor. I don't think there is any simple formula you can use, as the size of the shot would change things, the distance would change things, the material (sheetrock vs sheetrock and heavy wallpaper vs sheetrock and paneling) and whether you are talking one layer (side) or two.
 
My opinion.

Perhaps I should have posted my view in the first post.

My view is that any firearm powerful enough to stop an attach against a violent aggressor, will also pose a deadly threat to others if they are only separated by building materials. I base this on observation on what happens when you combine a single man with too much time on his hands, a shotgun and leftover building materials from a family bathroom renovation.

I was really curious to see if many people believed that smaller shot, "birdshot" would be stopped by, or made harmless by building materials. My curiosity came from comments from some people who stated that they use birdshot due to concerns over other family members IN the home.

Oh and the physics of the above is something I have played with (not quite to the point of a computer model, excel was more than enough for my needs), the wife is away, and I was bored. Bored engineers are more dangerous than strung out junkies, my wife is a SAINT!

Thanks for the replys.

VR

Matt
 
To assume that one could fire a shotgun load of bird shot at an interior wall from a few feet away and someone on the opposite side of that wall would be safe would be very imprudent. However, because individual small shot have limited energy and limited penetrating power, as distance increases OR as multiple barriers are breached the ability to penetrate falls off quickly. At 7 feet a shotgun blast will turn an attacker's chest or a sheetrock wall to a holey mess but there is little danger to someone on the opposite side of the house (assuming for this scenario the shot direction transverses a multiroomed building) One the other hand a .357 magnum might penetrate every interior wall and an exterior wall and still be potentially lethal.
 
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