"Overpenetration" and rifle rounds--the myth that won't die

[Cosmoline]

I once again ran into the myth that an intermediate cartridge out of a carbine cannot be used for home defense because it will penetrate houses and fly three miles. Who keeps spreading this nonsense? A properly loaded .223, 7.62x39, .30-30, .32-20, .357 etc. out of a short rifle or carbine actually poses LESS of an overpenetration concern than a handgun. The reason is simple--velocity. A carbine can get the bullet moving much faster than a standard handgun, and it's far easier to govern its performance on impact. A smaller HP round can be made to both do devestating damage to a human target but fall apart quickly on impact with soft framing materials and sheetrock. At lower handgun velocities it's much tougher to do this. HP rounds don't always open up and can get clogged. They can end up penetrating very far, certainly through many rooms of a house.

As has been pointed out here and elsewhere over and over and over again, the hard data on penetration explodes the myth of overpenetration for intermediate rounds.

Here's a thread re. the .223 with good data showing a max of 14" gel penetration for suitable rounds.

http://www.thehighroad.org/showthread.php?t=146306

And it's well known that the lighter .30-30 SP's penetrate about 13 inches and the heavier ones get to about 17" or 18"

 

[whm1974]

If you have the right bullets for those caliber then you may be right. 223 and 30-30 wouldn't be that hard to find proper ammo, but a lot of 7.62x39 HP doesn't expend at all or very poorly.

I notice there is some decent SD ammo for the M1 Carbine.

-Bill

 

[226]

Detailed Information Regarding Penetration Of .223 Ammunition

 

[MTMilitiaman]

Acknowledging that water jugs aren't human tissue (neither is geletin), my experience with the Wolf 122 gr HPs for the 7.62x39 is that they fragment violently. I recently went through a collection of 5 gallon buckets by filling them up with water and lining two of them immediately infront of each other, and in front of a bucket filled with sand. The FMJ flattened and yawed, as previous experience indicated it would, and was recovered in the sand bucket. The HPs, however, were a real surprise. It totally came apart on impact, basically turning inside out. A few peices of jacket was all we could find. It never even made it to the sand bucket. Both JHPs tested in the 10mm Auto made it to the sand bucket, so at least in a liquid medium, it would appear to be safe to suggest that the 7.62x39 so loaded is safer for home defense than the pistol round.

http://www.thehighroad.org/showthread.php?t=207700

And then there is always the Box O Truth...

 

[USSR]

It doesn't matter what cartridge or even what gun it is. It's simply a factor of velocity and bullet construction.

Don

 

[OldSchooler]

How about a 12ga with an ounce of #7 shot? By all accounts leaves a nasty wound (gasp) and breaks up on walls/sheetrock. Or is that 'Mythbuster' stuff too?

BTW, I read somehwere a while back that two sounds frighten home invading perps more than any others:

1. A LARGE barking dog
2. The sound of a pump shotgun being cycled into action.

 

[telomerase]

BTW, I read somehwere a while back that two sounds frighten home invading perps more than any others:

I don't have any statistics, but it seems that the sound of .223 rounds going off would have to beat either puppies or a sleepy homeowner short-stroking a pump.

Cosmoline's point is valid. Lots of people out there with .45s that are a lot more likely to exit their house than 55-grain .223s.

 

[MachIVshooter]

True that .223 and similar rounds have proven less likely to fully penetrate residential structures than many popular handgun rounds, but move up into larger calibers with more heavily constructed and just plain heavier bullets, and all bets are off.

 

[MTMilitiaman]

How about a 12ga with an ounce of #7 shot? By all accounts leaves a nasty wound (gasp) and breaks up on walls/sheetrock. Or is that 'Mythbuster' stuff too?

BTW, I read somehwere a while back that two sounds frighten home invading perps more than any others:

1. A LARGE barking dog
2. The sound of a pump shotgun being cycled into action.

I don't like the idea of using birdshot for defense. I've had it fail to stop ground squirrels at ranges I have in my house enough times that I am skeptical of its ability to stop a meth'd up body builder with a machete. And that is with a 26 inch barreled turkey choke.

A large barking dog is fine. Pumping a shotgun for dramatic effect is just as stupid when you do it as it is when Steven Segal does it. It gives away your position and lets the bad guy know you're armed. This might seem like the whole point, but it doesn't seem like a good idea to me considering you know neither about him. I'd rather keep the element of surprise until I know more of what I am dealing with. And I always felt that an unloaded firearm, esp an unloaded firearm designated for defense, was like a hammer without a head. It makes no sense to me, but then, it is entirely possible that my family does things differently.

 

[_N4Z_]

strokin' it! :-o

Many years ago, circa 1988, while stationed at Ft. Sill (living in Lawton OK), I had the occasion to "stroke" a pump to scare a bad guy.

I was home late from the field (2am) and was up playing Nintendo when I saw a head go past my window between the houses. Peeking out I saw a car in my neighbors driveway that should have not been there. She was out of town and I was feeding her cat. So.... grabbed my shoes, grabbed Mr. Rem870, and went out the back door. Snuck around the front where I found the dirtbag digging at her doorjam with a screwdriver. He was so intent on the task at hand that he didn't know I was there until I chambered a round. He went stiff and spent the next 15 minutes face down on the ground till the PD came to get him. Had he thought or moved poorly he would have recieved a face full of #4 and then a couple slugs if needed (was all I had). I would have been in deep poo too, but I was younger and that's what happened.

So that little trick can work, and did for me, but I wouldn't recommend it now.

 

[MAKOwner]

I take it the box of truth tests didn't make it to this board from AR15.com?

www.theboxotruth.com

The theory of the handgun rounds penetrating more sounds good, but most of the tests performed left the issue a little clouded at best. (I would argue it indicates that rifle rounds may indeed penetrate interior walls better especially if they hit some 2x4s and such along the way). Pretty much everything blew through the walls in the first tests (as many as twelve wallboards), although 5.56 yawed heavily making it a little inconsistent in flight path, and in some the tests where they spaced the walls out it had pretty heavy trajectory fluctuations... The sheetrock didn't cause the standard 5.56 rounds to fragment however. The rifle rounds blew through the pine boards significantly farther than the handgun rounds (5.56 again not fragmenting while going through 12 freakin boards), and the water jug tests seemed to break about even although some of the heavier rifle rounds did penetrate several more water jugs. The water and sand tests were about the only materials some of the rounds fragmented in, I don't think the ball 5.56 even fragmented in the water test though the JHP did.

He made a pretty good general conclusion in one of the tests I believe, something to the effect that anything that will reliably stop an attacker will penetrate the heck out of interior walls...

 

[Cosmoline]

We all know about the box o' truth. What tests are you referring to specifically and what point do you think they make?

 

[Outlaws]

The best physics data to date on this subject.

 

[U.S.SFC_RET]

Cosmoline
Why in the world would someone prefer a pistol if they had a carbine like you mentioned instead. In the Army a pistol is about useless unless the enemy is up close. The knockdown power (energy transfer) between the two can't even be compared.

 

[Cosmoline]

Beats me, but a lot of people will choose a short gun over a long for home defense. I've never been in the military, but I've tried hitting enough moving things with handguns to know how hard it is. I like *LONG GUNS*. Long guns hit what you aim at. Long guns fill the pot. Long guns should protect the home.

I blame Hollywood most of all for this. Too many people have seen too many action movies and taken them to heart.

 

[1911user]

A pistol can be easily used with one hand while the other carries a child, holds a flashlight, etc. Inside a house IS close range. Unless one has training on moving inside a confined structure with a longarm then moving about with a pistol makes it harder to be disarmed. The noise/blast is less with a pistol although both are loud especially indoors. A pistol is certainly a good choice for home defense use. There are other good choices each with their own downsides.

 

[Cosmoline]

Unless I lived in a tunnel, I would never choose a short gun over a long. The short gun is what you use until you get the long gun. I've shot too many living things with rifles and missed too many with handguns to have any doubts on the matter.

 

[mljdeckard]

Long guns are primary. Sidearms are BY DEFINITION, backup. The only reason we carry handguns everywhere is it's not practical to carry long guns, and it frightens the horses. ANY time you have the time, grab a long gun instead of a pistol.

However,

In the military, I used only 62 grain, steel core FMJ. This round is designed ONLY for penetration. And it does. Will 55 gr ball penetrate less? Sure. But this is STILL a hyper velocity round, which is highly unpredictable. I have personally seen this round follow bones, follow skin, etc. I went hunting mule deer once with some 'friends of friends', and one of them had been intimidated by larger rifles, so his friends encouraged him to get a .223, (Utah law only requires a center-fire rifle, no energy or caliber minimums. I would never advise someone to hunt large game with that round.) He did hit a deer, with a 55 grain soft-tip, and it pinholed, didn't expand. Fortunately, he put it right through the lungs, broadside, there was a .22 caliber hole entry and exit. ALL bullets are unpredictable in one way or another. And in real life application, Murphy's law applies. You're not going to stand mom behind ANY target and shoot it with ammo "guaranteed not to over-penetrate." Any 223 is going to be more likely to over-penetrate than a .45 230 grain hydra-shok moving 875 feet per second. And if the .45 DOES overpenetrate, it will be going a lot slower than a .223 that over-penetrates. There are exceptions to every 'likihood', but these are the extreme ends of the range pool.

My primary is a shotgun loaded with 00. My backup is an M-1 carbine, loaded with soft-points. (This round is less powerful than a .357 magnum, and the rifle size is something my wife is comfortable handling.) My walls are sheetrock, and I have 4 kids. Over-penetration is something I think about a LOT. Look at it this way, if you are looking for a hyper-velocity round, for MAXIMUM penetration, you will be using NATO steel core. Changing to a hollow-point and hoping for the best isn't my idea of minimizing over-penetration.

For anyone who wants to use a 5.56 for HD, I will STRONGLY recommend, use dedicated ammo. (Sub-sonic hollow-points.) And MAKE SURE the gas setup on your rifle will cycle them reliably first. For AK ammo, use American, commercial personal defense loads, nothing Russian.

 

[OldSchooler]

So what have we learned?
Something is better than nothing, surely is one lesson we can take away. I much prefer a long arm as opposed to a short one.
A handgun bullet and a rifle caliber bullet MAY penetrate into the next room, house, neighborhood seems to rise to the surface, too. Okay, compromise: I'll use BB shot or buckshot.
If no one minds, Ill keep the shorty shotgun and avoid the "stroking" of it for dramatic effect (never my intent - however one must do so to get it into action). The dogs stay, as well. Heck I'm feeding them they may as well be useful.

Thanks for the info.

 

[MTMilitiaman]

For anyone who wants to use a 5.56 for HD, I will STRONGLY recommend, use dedicated ammo. (Sub-sonic hollow-points.) And MAKE SURE the gas setup on your rifle will cycle them reliably first. For AK ammo, use American, commercial personal defense loads, nothing Russian.

My first deer was killed with a Ruger Mini-14 and the 55 gr SP behaved much in the same way as you described. I never once allowed that to confuse me into believing I would have had better results if the bullet had been going slower. Someone history regardless as pretty intelligent, a man by the name of Newton, told us that for every action there is an equal and opposite reaction. This means that all bullets, even the steel cored ones, are more likely to break up or deform at higher velocitues, because the target hits the bullet in effect just as hard as the bullet hits the target. Bullets don't go so fast they "zip right through" without expanding. A bullet that doesn't expand or deform at high velocity, say, 3100 fps, is even less likely to expand or deform at lower velocity, say 1300 fps. So claiming that a sub-sonic JHP is more likely to fragment than the same bullet driven at higher velocity shows an incredible lack of understanding in basic physics.
Now the slower bullet will have less momentum, which indicates less potential to penetrate. But even if this is so, it is unlikely that the bullet will penetrate much less, if at all, than the full velocity round if the full velocity round fragments, tumbles, or otherwise loses mass and/or increases frontal diameter.
If a bullet has shown itself to be unreliable in performance, then it is up to the user to change bullet designs. Bullet construction is very important for these purposes. But for all cases, with no exceptions, a bullet is always more likely to deform or fragment, or otherwise lose shape or mass, at a higher velocity. That is what being a physical law means. If your desire is to limit penetration through these methods, then your best bet is to increase velocity, not decrease it.

 

[Bartholomew Roberts]

Buckshot penetrates as well as any handgun bullet in most of the examples I've seen. Birdshot doesn't penetrate very far at all if you feel comfortable shooting at a lethal threat with something that won't penetrate several sheets of drywall (which even the lowly .22LR will do).

mjdeckard, I don't think your advice makes any sense. MTmilitiaman has made excellent points with the problems regarding your suggestion of subsonic hollow points for .223.

Any 223 is going to be more likely to over-penetrate than a .45 230 grain hydra-shok moving 875 feet per second.

According to this chart the .45 Hydrashok penetrates 16.6" in bare ballistic gelatin. Here is a chart of 8 different .223 loads from Federal. Not one of them (including both bonded-core bullets designed to penetrate and FMJ) exceeds 16.6" in bare gel. Some of them penetrate no deeper than 5.75" and probably do not penetrate enough to be used as self-defense loads.

It is important to remember that some bullets do behave more unpredictably and that rounds like M855 or M193 can fail to yaw or tumble as often as 25% of the time. In those circumstances, you will see more penetration than you want and the bullet may exit the 18" gel block. On the other hand, the ballistic tips, match bullets and some soft points can be very consistent in performance.

 

[MTMilitiaman]

If no one minds, Ill keep the shorty shotgun and avoid the "stroking" of it for dramatic effect (never my intent - however one must do so to get it into action).

Unless it was loaded to begin with. Then all you have to do is click off the safety

But hey it is your bacon. Protect it however you see fit.

 

[SaxonPig]

I'm not a ballistician or a physicist but even I know that a center-fire rifle bullet will penetrate further and deeper than handgun bullets (maybe comparing a .223 to a .454 Casull is an extreme). Note that the vests sold to cops are usually guaranteed to stop nearly all handgun ammo but as soon as a rifle is involved the warranty is voided.

I recall one tragic case a few years ago of a cop being killed by a 170 grain SP from a Model 94 Winchester. Not the most powerful rifle in the world yet it had no trouble defeating a vest that routinely stops .357 Magnum and .45 ACP pistol ammo.

Maybe I'm wrong but I believe that the average CF rifle bullet does indeed pose a much greater risk of penetrating interior walls than does the average handgun round.

 

[karaya]

How about frangibles? The producers promise that their miracle bullets will disintegrate on any hard surface.

 

[Ron Brooks]

But....

How many of the fragible ammo producers will stand behind a sheet of sheet rock, or even plywood and let you shoot their ammo at them.

Ron