"Over-penetration" Don't even worry about it.

[Denny347]

I've never had an issue with over-penetration. Under-penetration on the other hand....

We still talkin' ammo?

Were we talking ammo?

 

[BehindBlueI's]

Misses and overpenetration are different and one doesn't relieve you of the second. That's like saying you can't prepare for a house fire and a house burglary. Different things.

Maybe you don't care about over-penetration. Maybe you're so awesome you'll know exactly what your backstop is and be able to work the angles, you won't get tunnel vision, you'll have time to scan the entirety of the situation and the bad guy will give you the time to do so. Or you could end up like the fellow recently who was confronted with a road rage situation, shot the bad guy, but had the bullet pass through to the female passenger as well. Criminally, he's fine. Mentally he no longer wants to carry a firearm because he's burdened by shooting someone who didn't need to be shot. I have no idea if he'll face anything on the civil side.

I've got some photos of pass through bullets on my phone. I've yet to have anyone killed by a pass through, but I've had a couple injured.

 

[Vigilant]

Misses and overpenetration are different and one doesn't relieve you of the second. That's like saying you can't prepare for a house fire and a house burglary. Different things.

Maybe you don't care about over-penetration. Maybe you're so awesome you'll know exactly what your backstop is and be able to work the angles, you won't get tunnel vision, you'll have time to scan the entirety of the situation and the bad guy will give you the time to do so. Or you could end up like the fellow recently who was confronted with a road rage situation, shot the bad guy, but had the bullet pass through to the female passenger as well. Criminally, he's fine. Mentally he no longer wants to carry a firearm because he's burdened by shooting someone who didn't need to be shot. I have no idea if he'll face anything on the civil side.

I've got some photos of pass through bullets on my phone. I've yet to have anyone killed by a pass through, but I've had a couple injured.

Way to go Den...wait you’re not him?

 

[singlestacksig]

https://www.cnn.com/2020/02/06/us/crossbow-pitbull-attack-trnd/index.html

"Investigators believe that the bolt struck one of the dogs, went through the door and fatally struck the neighbor who was attempting to barricade himself from the attack."

 

[Frank_N_Stein]

Speaking of over-penetration, we had a shooting Wednesday night where someone inside a house fired at someone outside of the house. I'm not 100% sure, but I believe the rounds were .40s. The rounds went through the wall, through a 1X4 privacy fence, and into the neighbor's house. I'm not sure how far into the neighbors house they traveled because I didn't go inside. Luckily, the neighbor wasn't injured.

 

[bwframe]

...you could end up like the fellow recently who was confronted with a road rage situation, shot the bad guy, but had the bullet pass through to the female passenger as well. Criminally, he's fine. Mentally he no longer wants to carry a firearm because he's burdened by shooting someone who didn't need to be shot. I have no idea if he'll face anything on the civil side...

Any idea if the shooter here could have chosen a better self defense round, that might have had a better chance of stopping in the BG?

 

[Liberty Sanders]

Misses and overpenetration are different and one doesn't relieve you of the second. That's like saying you can't prepare for a house fire and a house burglary. Different things.

Maybe you don't care about over-penetration. Maybe you're so awesome you'll know exactly what your backstop is and be able to work the angles, you won't get tunnel vision, you'll have time to scan the entirety of the situation and the bad guy will give you the time to do so. Or you could end up like the fellow recently who was confronted with a road rage situation, shot the bad guy, but had the bullet pass through to the female passenger as well. Criminally, he's fine. Mentally he no longer wants to carry a firearm because he's burdened by shooting someone who didn't need to be shot. I have no idea if he'll face anything on the civil side.

I've got some photos of pass through bullets on my phone. I've yet to have anyone killed by a pass through, but I've had a couple injured.

I had a lifetime of law enforcement experience with small diameter, high velocity projectiles, which is why since my retirement my carry guns have always been slow moving big bores.

Has defense ammo improved and decreased the likelihood of over penetration? So they tell me. But I'm a mighty old dog.

 

[Tactically Fat]

Every bullet that leaves the barrel of a gun has a lawyer attached to it.

 

[BehindBlueI's]

Any idea if the shooter here could have chosen a better self defense round, that might have had a better chance of stopping in the BG?

Not really. I don't have the level of detail I would have if I were still a detective. I'm a field sergeant now and just happened to be "incident command" which, for some reason, is a thing now. My gut instinct is no, because I *think* the one that hit the passenger also hit the intended target in the arm. Any duty caliber cartridge will pass through in that case, but will still expand so should do less damage to the next person that's hit. the one before that I don't know what kind of bullet was used but it definitely wasn't an expanding one. Through the driver's torso, through the passenger's hand, into the door panel, and fragmented there. About the best I can say is it was relatively soft lead from the deformation and it probably lost it's jacket either in the auto glass or in the first person's torso. Since I don't get crime lab reports, x-rays, etc. that's about the best I can tell you. Note in the first case the window was down, second the bullet went through the glass first.

 

[Route 45]

I had a lifetime of law enforcement experience with small diameter, high velocity projectiles, which is why since my retirement my carry guns have always been slow moving big bores.

Has defense ammo improved and decreased the likelihood of over penetration? So they tell me. But I'm a mighty old dog.

Penetration has little to do with velocity alone and everything to do with bullet design. The point of improvements made to modern defensive ammo, especially 9mm, was not to reduce over-penetration. Quite the opposite, actually. Improvements were made to increase penetration to sufficient levels while also ensuring expansion. 850 fps is not slow, and is plenty fast to push a 230 grain slug through 2 or 3 people if the bullet is not designed for optimal expansion.

 

[Brad69]

I still can't believe BBI isn't wearing his nice suits and dress shoes?
He is in uniform with the regular people.

BBI's
Got a good story about a .357 that went through a bunch of stuff.

 

[BehindBlueI's]

I still can't believe BBI isn't wearing his nice suits and dress shoes?
He is in uniform with the regular people.

BBI's
Got a good story about a .357 that went through a bunch of stuff.

Yes, and it's a lot less stress to be with the regular people. I do kinda miss my hats, though. I visited them in the closet just this morning.

Hard cast .357 magnum will penetrate a whole lot of stuff. Adult male's torso, security door, exterior door, interior walls, and finally stopped by a door header or brick fireplace, depending on incident. I'm not sure the fireplace one was hardcast, it splintered on the bricks and wasn't recoverable except as smooshed lead bits. I've yet to see Critical Duty stop in a human's chest, either, although I think a spine hit might stop it. They expand just fine. They just keep on trucking. I've got a photo of a hole in one side of a leather jacket and a star shaped hole on the other side, so it expanded as advertised in the mean in between. I like Critical Duty .357 for trail carry but am a bit leery of carrying it in an urban environment based on those observations.

 

[MCgrease08]

https://www.cnn.com/2020/02/06/us/crossbow-pitbull-attack-trnd/index.html

"Investigators believe that the bolt struck one of the dogs, went through the door and fatally struck the neighbor who was attempting to barricade himself from the attack."

I came here to post this too.

 

[Trapper Jim]

Penetration has little to do with velocity alone and everything to do with bullet design. The point of improvements made to modern defensive ammo, especially 9mm, was not to reduce over-penetration. Quite the opposite, actually. Improvements were made to increase penetration to sufficient levels while also ensuring expansion. 850 fps is not slow, and is plenty fast to push a 230 grain slug through 2 or 3 people if the bullet is not designed for optimal expansion.

Placement far more important than Penetration. Most bullets don’t penetrate until they hit something.

 

[BehindBlueI's]

PThe point of improvements made to modern defensive ammo, especially 9mm, was not to reduce over-penetration. Quite the opposite, actually. Improvements were made to increase penetration to sufficient levels while also ensuring expansion.

Well, no. There's no trick to getting more penetration. Push the bullet faster and make it hold together. That's not a tough nut to crack and is easily done. Even .380 FMJ will penetrate a very tubby adult's abdomen completely. All the common duty calibers, magazine fed or revolver, and many of the subguns will over penetrate with no bone strike and many will with bone strikes. You're looking at 24" pretty handily and that's enough to be lethal to the next person in line, so to speak.

The issue with earlier 9mm (and some .38/.357 loads) was it expanded too much too fast and didn't get sufficient penetration. This was because they were doing what they were designed to do. The notion at the time was 6-8" of penetration was sufficient based on a frontal shot into the heart. Which is fine if you've got a front shot into the heart. It becomes more problematic when, say, the path is through the shoulder. It wasn't that 9mm or .38 was incapable of enough penetration, it was that it was being purposefully limited. Then, as is pretty common knowledge the 9mm silvertip fails to penetrate far enough in Miami, people learn that front on shots into nearly bare-chested assailants aren't always possible, and the penetration requirements evolve to require roughly double the amount of penetration.

The post-Miami thinking was handgun bullets needed to penetrate in a given window and do so in a variety of circumstances. That lead to the FBI testing protocols as we know them today. With a non-deforming bullet you can't stay in the window because if you penetrate enough in auto glass (which is also a good predictor of bone strikes) then you'll over penetrate in bare gel. You only have a gas pedal to adjust with. Deforming ammo also gives you a brake when designed so as not to start deforming until in "meat" as opposed to in dry wall, auto glass, etc. Deformation has the added benefit of some extra tissue damage, but that's not the biggest gain. Barrier blindness is, along with reducing deflection. Even when it does over penetrate (and it can, nothing's foolproof and limb strikes especially won't stop them) the expanded round will penetrate less in the next "meat" in line since it's already expanded. Injury sucks but death sucks more.

 

[Route 45]

Well, no. There's no trick to getting more penetration. Push the bullet faster and make it hold together. That's not a tough nut to crack and is easily done. Even .380 FMJ will penetrate a very tubby adult's abdomen completely. All the common duty calibers, magazine fed or revolver, and many of the subguns will over penetrate with no bone strike and many will with bone strikes. You're looking at 24" pretty handily and that's enough to be lethal to the next person in line, so to speak.

The issue with earlier 9mm (and some .38/.357 loads) was it expanded too much too fast and didn't get sufficient penetration. This was because they were doing what they were designed to do. The notion at the time was 6-8" of penetration was sufficient based on a frontal shot into the heart. Which is fine if you've got a front shot into the heart. It becomes more problematic when, say, the path is through the shoulder. It wasn't that 9mm or .38 was incapable of enough penetration, it was that it was being purposefully limited. Then, as is pretty common knowledge the 9mm silvertip fails to penetrate far enough in Miami, people learn that front on shots into nearly bare-chested assailants aren't always possible, and the penetration requirements evolve to require roughly double the amount of penetration.

The post-Miami thinking was handgun bullets needed to penetrate in a given window and do so in a variety of circumstances. That lead to the FBI testing protocols as we know them today. With a non-deforming bullet you can't stay in the window because if you penetrate enough in auto glass (which is also a good predictor of bone strikes) then you'll over penetrate in bare gel. You only have a gas pedal to adjust with. Deforming ammo also gives you a brake when designed so as not to start deforming until in "meat" as opposed to in dry wall, auto glass, etc. Deformation has the added benefit of some extra tissue damage, but that's not the biggest gain. Barrier blindness is, along with reducing deflection. Even when it does over penetrate (and it can, nothing's foolproof and limb strikes especially won't stop them) the expanded round will penetrate less in the next "meat" in line since it's already expanded. Injury sucks but death sucks more.

Not sure who you are arguing with, but you basically just restated what I posted. I did say defensive ammo, not FMJ. I know any FMJ will likely penetrate all the way through even a corn-fed Hoosier. Old 9mm defensive rounds often under-penetrated, notoriously in Miami. New defensive ammo is designed to increase penetration (vs. the old Silvertips, etc.) to sufficient levels while ensuring more reliable expansion.

 

[Route 45]

Placement far more important than Penetration. Most bullets don’t penetrate until they hit something.

Also, water is wet.

 

[Dead Duck]

Well, no. There's no trick to getting more penetration. Push the bullet faster and make it hold together. That's not a tough nut to crack and is easily done. Even .380 FMJ will penetrate a very tubby adult's abdomen completely. All the common duty calibers, magazine fed or revolver, and many of the subguns will over penetrate with no bone strike and many will with bone strikes. You're looking at 24" pretty handily and that's enough to be lethal to the next person in line, so to speak.

The issue with earlier 9mm (and some .38/.357 loads) was it expanded too much too fast and didn't get sufficient penetration. This was because they were doing what they were designed to do. The notion at the time was 6-8" of penetration was sufficient based on a frontal shot into the heart. Which is fine if you've got a front shot into the heart. It becomes more problematic when, say, the path is through the shoulder. It wasn't that 9mm or .38 was incapable of enough penetration, it was that it was being purposefully limited. Then, as is pretty common knowledge the 9mm silvertip fails to penetrate far enough in Miami, people learn that front on shots into nearly bare-chested assailants aren't always possible, and the penetration requirements evolve to require roughly double the amount of penetration.

The post-Miami thinking was handgun bullets needed to penetrate in a given window and do so in a variety of circumstances. That lead to the FBI testing protocols as we know them today. With a non-deforming bullet you can't stay in the window because if you penetrate enough in auto glass (which is also a good predictor of bone strikes) then you'll over penetrate in bare gel. You only have a gas pedal to adjust with. Deforming ammo also gives you a brake when designed so as not to start deforming until in "meat" as opposed to in dry wall, auto glass, etc. Deformation has the added benefit of some extra tissue damage, but that's not the biggest gain. Barrier blindness is, along with reducing deflection. Even when it does over penetrate (and it can, nothing's foolproof and limb strikes especially won't stop them) the expanded round will penetrate less in the next "meat" in line since it's already expanded. Injury sucks but death sucks more.

Huh.
Well that settles it. Hamburger tonight.

Thank You!

 

[Principal Skinr]

​Anyone who says that they give NO consideration to the possibility of overpenetration has no business carrying a gun.

Just my non-expert 2 cents.....I've considered it a great deal and found it to be not so high on the worry list as a number of other things, such as hitting the target in the first place.

Btw, while thinking about this, I agree with the thoughts that have been posted about underpenetration. So we're buying ammo and guessing at the sweet spot for penetration. Not too much, not too little. So many variables. Again, I'll worry more about shot placement with whatever ammon I choose.

So, we assume what our ammo will do, when the truth is we have no idea of many variables that could be in play. So, everything is really a compromise. So again, I worry about recognizing a threat, how quickly I can make a decision, how quickly I can draw, and how accurately (while under great stress) I can shoot. In fact, that last one is the big one because I don't think I can even come close to simulating the stress one would feel when being under threat of death and having to shoot in self defense. So we do the best we can, which is an educated guess, at best.

Those are more of the things I think about. As far as ammo, I try to pick what I think is the best compromise for the situation. There are lots of types of ammo that can generally meet my percieved needs.

 

[BehindBlueI's]

Not sure who you are arguing with, but you basically just restated what I posted. I did say defensive ammo, not FMJ. I know any FMJ will likely penetrate all the way through even a corn-fed Hoosier. Old 9mm defensive rounds often under-penetrated, notoriously in Miami. New defensive ammo is designed to increase penetration (vs. the old Silvertips, etc.) to sufficient levels while ensuring more reliable expansion.

Historically, FMJ is also defensive ammo, as is SWC, lead ball, etc. Deforming ammunition, other than simply softer lead, is still a fairly recent innovation. I didn't realize you were using 80's hollow-points as the base line. As a result I was probably addressing what I thought you said vs what you said.