The Myth of "Over Penetration"

[Jeff Higgins]

No, you perverts, not that kind - we're talking firearms here. I started out posting this as a reply on another thread, but it started to take on a life of its own, so I figured I would give it a life or its own. Anyway...

"Over penetration" has got to be the most over used term of all time in the defensive handgunning world. I would be surprised to learn of a documented case where a handgun bullet went through the bad guy and went on to injure anyone else in a self defense shooting. I believe the chances of this actually happening are effectively zero.

In sharp contrast, there are far too many documented cases of failures to penetrate sufficiently to stop the fight. Too many good guys have lost their lives over this one. Over no more than marketing hype and disinformation.

"Over penetration" is no more than a bull shyte myth perpetrated by the ammo manufacturers and their cheerleaders in the gun press. It's marketing, pure and simple, directed at the less than savvy ammo buying public. They understand most folks will never shoot anything more threatening than a piece of target paper or a pop can, so they will never get to (or have to) see for themselves just how well their chosen brand of designer ammo performs on live targets.

Bottom line is, there is no such thing as too much penetration. The idea that a bullet design can somehow be matched to its intended cartridge to provide just the right amount of penetration, not too much now (but at the same time not too little), and somehow be made to stop when it reaches the vitals (but not before) is laughable. There are simply far too many variables. Size and weight of your adversary, what they are wearing, what angle you hit them from, and more all conspire to make it impossible to predict just how much penetration is "enough" vs. how much is "too much".

Add to that the fact that any particular designer hollowpoint is more than likely loaded in a number of cartridges that share the same bullet diameter and launch them at widely varying velocities (.38 Special and .357 Magnum, for example). How can the same bullet possibly perform to the same level of "ideal" penetration when one cartridge starts it at 800 fps, and the other starts it at 1,300 fps? They simply cannot.

In light of all of this, it is never a mistake to load up with ammo that provides maximum penetration for the caliber in question. This usually means the heaviest bullet the caliber will handle. It never means hollow points, no matter how pretty the mushroomed bullet in that ad may look, or how nasty the "wound channel" looks in ballistic gelatin. Neither represents real world bullet performance. It's all directed at the vast market comprised of shooters that will never never gain any first hand experience, nor be likely to meet anyone who has.

Like I've mentioned in other threads, I have never shot a human being and hope to God I never will. I have, however, long since lost track of how many game and non-game animals I've shot. Most with rifles, of course, but dozens and dozens with hand guns as well. A good number of those animals are about our size, some smaller, some much bigger. I've tried hollow points of various pedigrees, every one of which was touted as the "latest and greatest" of the time. Damn near every one of them failed to penetrate sufficiently to put the animal down quickly. Even .357 and .44 mags loaded to the gills, even on critters as small as coyotes. At least these kinds of animals run off when hit (some of them for miles...), so I was never put in danger by any of those failures. But, I'm here to tell you - I have seen some pretty heavily loaded hollowpoints from magnum revolvers simply go "splat" on the sides of mule deer, coyotes, pronghorns, and such, providing no more than an inch or two of "penetration".

In sharp contrast, the ones I hit with non-expanding bullets (typically my own hard cast semi wadcutters) at even moderate velocities go down very quickly. They go down quickly because the bullet goes all the way through, therefor reaching the vitals every time. That is what kills, and more importantly, incapacitates quickly. In my personal experience, a moderately loaded 250 grain hard cast semi wadcutter at, say, good stiff .44 Special or .45 Colt velocities (under 1,000 fps), kills far, far more effectively than a lighter hollowpoint going 500-600 fps faster. I've seen it myself on too many occasions.

Granted, my hunting experiences encompass revolvers only, as there really are no auto loaders that I feel make suitable hunting handguns. But the same principles apply. Probably more so, with the average auto loader giving up so much in terms of case capacity, and therefor bullet weight and velocity, to revolvers with similar bore sizes. With these "capacity challenged" chamberings, the auto loader becomes even more critical with regards to achieving enough penetration to be reliably effective. In these guns, nothing beats the heavy, truncated cone, flat point FMJ. The round noses are a distant second behind them, but the designer hollowpoints aren't even in the race. I won't even consider the damn things.

[masraum]

Originally Posted by Jeff Higgins

No, you perverts, not that kind - we're talking forearms here.

Wait, you are not or are talking to the perverts???

[Rick Lee]

Ok, so what's with those ballistic gelatin slabs that show a garden variety JHP penetrating 10-12" with heavy clothing in front of it? I also have never heard of an overpenetration issue in a defensive shoot. But I know my own center mass less than 12" thick and I'm kind of big and usually not wearing anything thicker than a t-shirt. Aren't those ballistic gelatin slabs made to simulate human tissue in thickness and resistance?

[masraum]

Interesting post. Surely something to think about.

[masraum]

Originally Posted by Rick Lee

Ok, so what's with those ballistic gelatin slabs that show a garden variety JHP penetrating 10-12" with heavy clothing in front of it? I also have never heard of an overpenetration issue in a defensive shoot. But I know my own center mass less than 12" thick and I'm kind of big and usually not wearing anything thicker than a t-shirt. Aren't those ballistic gelatin slabs made to simulate human tissue in thickness and resistance?

Something that I've always wondered about, if the gelatin is supposed to simulate flesh, is that a gut shot, or is that counting stuff like ribs, sternum, etc...?

[Jeff Higgins]

Originally Posted by Rick Lee

Ok, so what's with those ballistic gelatin slabs that show a garden variety JHP penetrating 10-12" with heavy clothing in front of it? I also have never heard of an overpenetration issue in a defensive shoot. But I know my own center mass less than 12" thick and I'm kind of big and usually not wearing anything thicker than a t-shirt. Aren't those ballistic gelatin slabs made to simulate human tissue in thickness and resistance?

Ballistic gelatin tests only do one thing - they demonstrate how ell bullets penetrate and expand in ballistic gelatin. That stuff in no represents a living, breathing person's tissue. A great deal of effort has been put forth to somehow correlate how a bullet behaves in that stuff to how it behaves in real living tissue, but has been so far unsuccessful. The stuff is too consistent, too homogenous. It has no fiber, has no bone, has no variation in density, and no variation in fluid content as flesh and organs do.

Advertising types love it, though, because of how nicely hollowpoints are formed into pretty mushrooms in it, and how "shocking" the initial wound channel looks in it. It makes the temporary wound channel look permanent and quite impressive, so the ad guys love to tout the "shocking" qualities of their particular hollowpoints. Problem is, one we get above about the size of a ground hog (rock chucks out here) and below the velocity of a .220 Swift or .22-250, "shock" becomes a myth as well. It just doesn't happen.

Death is caused by the permanent wound channel. Incapacitation is not caused by "shock" in anything near the size of humans. Incapacitation is most effectively caused by hitting the central nervous system, with causing rapid blood loss in second place. Entry wounds generally don't bleed anywhere near as much as exit wounds, and hitting anything important in either the central nervous or circulatory systems requires penetration. Not expansion.

[legion]

Originally Posted by masraum

Wait, you are not or are talking to the perverts???

This seems on-topic...

[Bill Douglas]

not that I would recommend it...

[johnnywishbone]

weatherby with a .257?

[Jim Bremner]

The 12" of penetration comes from needing to go in the arm, and into the chest.

It came from the Miami shootout if I've been told right.

[Bill Douglas]

Originally Posted by Jim Bremner

The 12" of penetration...

Show off.

[DanielDudley]

Shoot for the heart, Ramone.

[red-beard]

Jeff, I know you're going the right direction with this. There is another thing to consider beyond regular penetration. Exit through skin. Skin is tough. The bullet has already been reduced in speed by going through flesh. Exiting the skin means it is really slow. Hand gun ballistics are very different than rifle. The velocities are 1/2 to 1/3rd.

This is why I load my .380 with FMJ and my .45 with alternating Corbon and FMJ. If I had access to commercial semi-wad cutters, I would use those.

[Rick V]

230gr.fmj in my 45acp is my standard "friend"

[Tobra]

my concern is more for the shots that miss

trust and believe that cavitation matters, probably not as much as the size of the hole, but it does bad things to tissue

[Schrup]

10mm over penetrates my wallet.

[azasadny]

Jeff,
The other "myth" that drive me crazy is the "big gun = big recoil" myth! Heck, my little 15 year old daughter fired my Remington Rand M1911A1 .45ACP last weekend at the range with no problems at all. The gun is heavy, so I helped her support the gun, but she handled the mild recoil just fine. If you compare the recoil of a full frame gun to a mini, like my wife's Ruger LCP at 9.3oz, the Ruger has an uncomfortable recoil!

[UconnTim97]

Art,
You aren't kidding about recoil with the LCP. I usually only run two or three mags through it at the range to stay proficient. The +1 magazine extension helps a little.

[Mike C]

Originally Posted by Rick V

230gr.fmj in my 45acp is my standard "friend"

This works for me as well!

[Esel Mann]

Jeff, interesting insight on the ballistics gel being more/mostly a marketing tool.

Your point about it being too homogenous to be a good representation for the human body makes perfect sense.

Do the firearms/ammo designers (not the marketeers) use the same (b. gel) while carrying out the design process or do they use something more representative of the human body, for example pig to get a better handle on the many variables?