Over Penetration Guidelines

[dwever]

Returned from 5 years in Alaska back to Alabama. Sold my PC S&W .460, and got the .357’s out of storage.

For EDC I am running Federal Premium Personal Defense Ammunition 357 Magnum 154 Grain HST JHP. My concern is, at 1,340 fps (615 ft. lbs. of muzzle energy), is that a recipe for over penetration?

Of the three smaller .357 Magnum revolvers, the Korth 3” Mongoose really has superior DA, so it is getting the most time. All S&W’s tuned by TK Custom.

 

[rockquarry]

How do you measure "overpenetration"? Can it be defined? I suppose it's better than underpenetration. This seems to be more textbook theory than a problem.

 

[rwsmith]

I look at two tests....

Between Paul Harrell with his chrono and 'meat target' (with the high tech fleece backstop) and Lucky Gunner with their heavy cloth and gelatin tests (they list velocity), I can pretty well see which ammo expands reliably and limits penetration.

I honestly think that penetrating (being a self defense problem and not a hunting scenario) requirements assigned by the FBI are a bit too much for citizen self defense. 12" to 18" in a front facing attack is pretty big for a majority of people, so I look for ammunition on the lower end of that range with very good expansion.

 

[Alk8944]

If you are compelled to shoot an adult human of average size that load will certainly be capable of penetrating through-and-through, as will any .357 Magnum load! Most standard handgun calibers are capable of through-and-through penetration of an average human, including the .22 Long Rifle under some situations. Over-penetration is a completely overblown concern! The greater concern is shots that totally miss the intended target to strike a bystander.

If you are that concerned the answer is to carry standard pressure .38 Special ammunition instead of any .357 Magnum load.

I strongly suggest to anyone who is concerned about over-penetration, or any subject related to defensive use of firearms, watch Massad Ayoob's series of videos found on You Tube. Mas. is a recognized authority on the subject and speaks the truth, unlike the vast majority of You Tube posters that are full of "baloney" or whatever stronger word you care to substitute!

 

[LVSteve]

Between Paul Harrell with his chrono and 'meat target' (with the high tech fleece backstop) and Lucky Gunner with their heavy cloth and gelatin tests (they list velocity), I can pretty well see which ammo expands reliably and limits penetration.

I honestly think that penetrating (being a self defense problem and not a hunting scenario) requirements assigned by the FBI are a bit too much for citizen self defense. 12" to 18" in a front facing attack is pretty big for a majority of people, so I look for ammunition on the lower end of that range with very good expansion.

You must have skinny gangbangers where you live. With some of the dubious man (and women) mountains I have seen in this town over penetration is unlikely to be an issue. Throw in a little meth or crack and I'm thinking 7.62x39 as a starting point.

 

[dwever]

Maybe overblown in my mind. Years ago worked a dog shooting where two trespassing domestic pits were dispatched with a single 7mm rifle round which of course is a completely different conversation. The farm owner did not go to jail.

 

[rockquarry]

Maybe overblown in my mind. Years ago worked a dog shooting where two trespassing domestic pits were dispatched with a single 7mm rifle round which of course is a completely different conversation. The farm owner did not go to jail.

Good for you. Much better than fixating on something of little practical worth.

 

[Claymore33]

Worried about over penetration ? Try .38 SPL + P

 

[Bald1]

Is the concern about what’s beyond the target? Or the bullet passing through without depositing all its energy in the target?

 

[Doug M.]

Over penetration can be, but shouldn't be, a problem. Missing is a far greater problem, and placement is the first consideration if you have to shoot a human aggressor. (Or an animal.) Adequate penetration is not an option, and if you look at the detailed study of the FBI's 1986 shooting in (suburban) Miami, under penetration was an issue. Their experience was an impetus for the ballistic studies done by Fackler, at al (IWBA) and continued by Dr. Roberts. Among other lessons: if you expect a problem and can't be elsewhere, pistols are not the answer. Long guns are.

The penetration standard in calibrated ballistic gel is not a direct correlation of the amount of penetration needed on a human - it is a means of having a consistent measure, just like running times in fitness tests are an expedient manner of testing oxygen uptake. If you have to shoot from the side, the round must penetrate the arm complex to enter and penetrate the vitals (high center mass).

Me? I usually carry an auto-pistol, and I chose them based on my performance. If I carry a revolver, my usual preference is a medium velocity lead SWC, such as a standard .38 in my M66. I can and have qualified with full power magnum loads, but objectively, the odds of good placement and rapid repeat shots are far better with the .38s.

I have on many occasions cited to the Patrick and Hall text (3rd edition). The ballistic lessons provided are not directly applicable outside LE, but they are a closer fit than most misinformation. Perfect penetration is when the bullet stops and falls in the clothing on the far side just after exiting the chest. It's a rarity, or a fantasy, and not what I consider. One needs to know the proper targeting on a human aggressor and place rounds there consistently.

 

[robertrwalsh]

Every time I see this question I am remind the of "actual, field testing" of this notion. Back when dinosaurs still roamed the earth and the NYPD moved from .38 special to 9mm they contemplated on this. The department (for political reasons) demanded that the troops be issued 9mm military ball. In the first year they had three overpenetration shootings which killed two people and injured one. If I recall correctly one of those deaths was another police officer. After that first year the "politicians" in the department changed their mind and listened to their own tech people and went with the "evil and horrible" hollow-point ammo. Theory is nice. Actual field experience, even a small number of incidents, is IMHO at least as useful and maybe more so. In any event you should go with what you feel comfortable with. Personally when I am packing a revolver in the city (as opposed to bear country) I go with .38 special +P load.

 

[rwsmith]

You've got.....

You must have skinny gangbangers where you live. With some of the dubious man (and women) mountains I have seen in this town over penetration is unlikely to be an issue. Throw in a little meth or crack and I'm thinking 7.62x39 as a starting point.

You've got FAT meth heads where you live?? I guess I'm not used to the Appalachian variety.

 

[rwsmith]

Paul Harrel showed....

Is the concern about what’s beyond the target? Or the bullet passing through without depositing all its energy in the target?

He showed that both 9mm and .380 FMJ went clean through his meat target with plenty of oomph to spare. Bullet choice is all important.

 

[rwsmith]

I'd definitely....

Is the concern about what’s beyond the target? Or the bullet passing through without depositing all its energy in the target?

Be more concerned about what's on the other side.

 

[rockquarry]

He showed that both 9mm and .380 FMJ went clean through his meat target with plenty of oomph to spare. Bullet choice is all important.

Shooting live game and pieces of dead meat aren't really valid comparisons. This sounds YouTubish but may be close enough for some.

 

[rwsmith]

This is true, but....

Over penetration can be, but shouldn't be, a problem. Missing is a far greater problem, and placement is the first consideration if you have to shoot a human aggressor. (Or an animal.) Adequate penetration is not an option, and if you look at the detailed study of the FBI's 1986 shooting in (suburban) Miami, under penetration was an issue. Their experience was an impetus for the ballistic studies done by Fackler, at al (IWBA) and continued by Dr. Roberts. Among other lessons: if you expect a problem and can't be elsewhere, pistols are not the answer. Long guns are.

The penetration standard in calibrated ballistic gel is not a direct correlation of the amount of penetration needed on a human - it is a means of having a consistent measure, just like running times in fitness tests are an expedient manner of testing oxygen uptake. If you have to shoot from the side, the round must penetrate the arm complex to enter and penetrate the vitals (high center mass).

Me? I usually carry an auto-pistol, and I chose them based on my performance. If I carry a revolver, my usual preference is a medium velocity lead SWC, such as a standard .38 in my M66. I can and have qualified with full power magnum loads, but objectively, the odds of good placement and rapid repeat shots are far better with the .38s.

I have on many occasions cited to the Patrick and Hall text (3rd edition). The ballistic lessons provided are not directly applicable outside LE, but they are a closer fit than most misinformation. Perfect penetration is when the bullet stops and falls in the clothing on the far side just after exiting the chest. It's a rarity, or a fantasy, and not what I consider. One needs to know the proper targeting on a human aggressor and place rounds there consistently.

Missing is MY problem that I am duty bound to improve the best I can. The expansion is the ammo manufacturer's job. Nothing is sure, but I'll take the best odds on what will and won't work right.

No, gel isn't a perfect substitute, but it's the best constant simulation they have and authorities use it. How the testing is done makes a lot of difference, too. In fact, Lucky Gunner uses the clear gel for most of their testing which is not quite the same as the organic gel that is used in 'official' testing. That's why I like the 'meat targets'. They are very close to real world scenarios.

You can take a LOT away from the big shootings the FBI and police were involved in. But again, I think that most SD situations are going to be at very close range and most likely head on. Even if I do have to make a side on shot at some distance, the ammo I choose should handle the job and I don't have to pull the trigger just once. I can accept ammo that is just over the 12" penetration if it has consistent expansion characteristics.

In an SD situation outside my home, I'll HAVE to use a pistol. In the house I have 9mm carbines that I'd pick if given the chance.

I know a little about anatomy, but center of mass or the head are my targets. If I have to shoot low, still center of mass.

 

[rwsmith]

It seems like the best out there...

Shooting live game and pieces of dead meat aren't really valid comparisons. This sounds YouTubish but may be close enough for some.

..unless you are going to shoot live subjects. What do you guys expect. Really?

What's wrong with something being on Youtube if it's seriously well done? 'Youtubeish' sounds like an unfair slight. Sure youtube has a lot of bullcrap, but I avoid it.

 

[StrawHat]

Maybe this is not the way what most shooters think. I am not sure what the average thug weighs but the average of the white tailed deer I have shot is right around 175 pounds. I like complete penetration for my hunting loads, from any angle.

My edc revolver carries the same load my hunting revolver does.

Now, I have used it to harvest deer. But so far, thugs have avoided me.

Kevin

 

[rwsmith]

Since I don't use .357 ammo for SD.....

... I checked the Lucky Gunner site. Speer Gold Dots 125 grain and 158 grain are off the scale after 30" of penetration!!!

If I want to use it I'll save my money and use FMJ instead of Gold Dots.

Funny thing is, most of the ammo tested performed well and stopped in the 12" to 18" range. I would have expected .357 Mag to tend more to the top end if not over penetrate.

 

[Pisgah]

Overpenetration is vanishingly rare as a problem in gunfights. It's missing your target that is the biggest threat to innocent bystanders.