Lethality of 9mm FMJ at very low velocity?

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.455_Hunter

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What would you describe the lethality potential of a 124 gr 9mm projectile at roughly 350 fps and 45 fpe?

What if it struck the torso, head or even the eye with low resistance path into the cranium?
 
If going for 350 FPS there’s a chance your low pressure load could result in a bullet getting stuck in the rifling.

Assuming it hits the person just right I’d guess that it could be lethal. Put on a thick sweater and a leather jacket and I’d bet the bullet doesn’t even penetrate the skin.
 
350fps isn't low velocity it's barely moving in ballistic terms.

I'd imagine a 9mm with that velocity only getting a few inches in human flesh, depending on the distance.


What is the purpose behind the question?
 
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Residual projectile velocity after penetrating building materials.


Well a 9mm isn't going to lose a lot of velocity going through a couple walls of drywall or glass. Now if you're talking about wood/brick/concrete theres virtually no velocity left if it were to make it through.

I'm curious why you're asking. HD?
 
The actual real world results of gunshot wounds can be so random that I'd never want to bet on them - one way or the other... and the response of the shooting victim to a gunshot wound isn't something I'd ever want to bet on either... One individual takes more than one round, center of mass and survives just fine.. The next guy takes a relatively minor wound to an arm or a leg and dies within a short time frame... go figure...

Put simply, violent actions with shots fired is something to be avoided at all costs... That's something I learned early on in a career that was 22 years on the street... Besides, the good guys don't always win...
 
Residual projectile velocity after penetrating building materials.
It's a good question, but an impossible answer.

We can easily define a bullet/velocity combination that is acceptably reliably lethal. It's approximately impossible to define a combination that's reliably NOT lethal.

I've been hit by a 230gr .45 slug going <300fps. . . it left a smudge on my shirt; if it'd hit me in the eye I'd be blind or dead. Is that reliably safe?

The only acceptably reliably safe bullet/velocity combination is "no bullet", or "zero velocity".
 
A Red Ryder spits out a 5.3 gn BB at 350 FPS advertised (less than that if you have a chronograph) and we all know “you’ll shoot your eye out”, with it.

It doesn’t take a lot of speed, weight or energy to make something lethal but they will help.

No bullet can also be lethal, folks have died from blanks before, thinking they were ”safe”.
 
For some perspective, 350 feet per second is 238 miles per hour. But is only 34 foot pounds of energy, about 1/3 of your average 22lr energy.

A 5.3gr BB at 350fps is 1 foot pound of energy.

My GUESS is that it would ruin your day if you were hit anywhere besides in the head, and a head shot would likely ruin your month, or more.
 
At 350 FPS even most head shots wouldn't be anything but a graze. The bullet would just defect off your skull unless it hits you just right.
 
Really tough to try to simulate the problem by loading down, and firing a projectile at that assumed velocity into gel or whatever. Two things to consider:

1) The real world example might involve a projectile that is flying with characteristics you haven't emulated. For example it might be unstable, have a presentation that is not nose-first, and have pieces missing from it.

2) Every projectile that started at a velocity greater than the assumed velocity but which was retained in a human body, had a part of its trajectory dropping from 350 fps to 0 fps. I don't have stats with me at present but I can provide them when I get home: a significant number of gunshot cases I have dealt with are penetrating injuries (all of the projectile components that entered the body at the entrance site remain in the body, even if the projectile splits up or yaws and is deformed.) That last part of the trajectory is where the bullet is much more likely to be subject to the influence of soft tissue planes and may be deflected accordingly even if bone is not involved. To have this trajectory starting at the skin means you have even greater possibility of deflection since you have to overcome (in most cases) skin first as a minimum. I'm not even talking about clothes here!

I think the variables involved are even more than what somebody might try to model with plain gunshots into gel (compared to soft tissue gunshots at a similar velocity where the projectile arrived stable and in good condition).
 
Supposedly David killed Goliath with a rock, but it was probably bigger than 9 mm...

Bigger than 9mm for sure... :D

Slings were widely used in ancient warfare, the Romans used cast lead bullets from 500gr to 1000gr, at velocities of 200 to 300 fps.

A shot in the head would kill you DRT... :cool:

The church tells the story with David as the underdog, because Goliath was a giant. Actually, Goliath showed up with a spear for a gunfight... He didn't stand a chance: David was skilled with his sling, he knew and trusted his weapon, knew and trusted his ability. He was far from the rosy, effete young shepherd depicted at your Sunday school: hardened outdoorsman, used to deal with apex predators and kill them.

Take an eighteen years old kid from Alaska, who's been hunting in brown bear territory since he was a toddler, and send him with a Howdah double-barrel pistol against a badass 7' bodybuilder on steroids holding a spear. Who you're going to bet on?
 
.455_Hunter
Even with your data, they are still many variables to be mention.
Projectile entering to a none deathly anatomy part (arms, legs and the like) it might cause a severe damage but not a casualty.
On the other hand spinal cord through back, lateral plane it might ground you.
Concern about a bullet struck in the barrel are very real and more at that fps, I am not very experienced on reloading matters.
However, at that grain a good defensive round it might be a good selection.
 
Here's a lucky escape, from one of my case files.
A guy was walking along, minding his own business and was struck on the right side of the head in the temporal region by a bullet. He didn't see or hear where it came from, and it did not penetrate very deeply. He was not incapacitated in any way and arrived at hospital fully alert.
The radiographs reveal a bullet which is probably an FMJ, known to be deformed when you compare the AP view to the lateral. Look at the ratio between the height and width of the bullet on both radiographs. It is evident radiologically that the bullet has been flattened somewhat:

upload_2019-7-11_20-9-9.png

The bullet was palpable and was removed under local anaesthetic the same evening. Sure enough, it was a deformed FMJ with post-discharge rough striations on one side. What we have here is an errant shot which lost a lot of energy during a ricochet.
The temporal region of the skull is very thin. This bullet did not penetrate the bone, it was lodged in a subcutaneous position easily accessible in the ER.
The paperclip is a skin breach marker. One possible trajectory has the bullet coming from behind and above the victim. Even if it penetrated the brain, he would be unlucky to be killed, but would take frontal lobe damage. That relies on a big assumption that the trajectory stayed true and the bullet did not deflect off the inside table of the skull vault.
The point is, this bullet lost a lot of energy. If either the shooter or the victim was differently positioned, this could have been a complete miss or a fatality.
No two gunshot injuries are the same!
 
Many people have died from being hit with a bullet from a .22lr handgun. Many people have been hit with a 30-06 bullet from a M1 Garand or 1903A3 and continued to fight back. I think your answer lies somewhere between these 2 scenarios.
 
To have this trajectory starting at the skin means you have even greater possibility of deflection since you have to overcome (in most cases) skin first as a minimum. I'm not even talking about clothes here!

Soooo...

The lesson here is "only shoot naked perps"?

:D:D:D

Good points, though.

Honestly, the only reasons I can think of to drop muzzle velocity down to the 350 fps range would be testing and trick shots.

Most 9mm handguns are autoloaders. You ain't gonna be cycling the action at 350 fps...which kinda limits the use of such ammunition to single shot acts.
 
Residual projectile velocity after penetrating building materials.

This is something I put a lot of thought into. I have read plenty of the "over penetration is a myth" arguments.

The core flaw in their argument is that they work from the assumption that they will never miss. They extend that to the firm belief that no responsible gun owner could miss. The next leap is the position that a gun owner who builds their plan around the idea that some shots will miss is an irresponsible gun owner.

These people build their plan around the belief that when everything around them is at its worst, and potentially most chaotic, they will perform at their best.

Back to guns, I have seen several tests online that show that the .223 with a light bullet, hunting loads, has significantly less residual potential after drywall penetration than 9mm. I, quite literally, just ordered a .22tcm rifle because I want to test its residual potential under the same conditions. It seems that it should, after all, it is shooting an even lighter bullet, again ay high velocities.

I ordered it yesterday, so it will be at least a month before I do any testing.
 
Back when i shot a bunch of bowling pins I worked up some loads that hit hard enough oomph not to bounce but enough to knock the pin off the table. Pins are pretty tough.
 
Most 9mm handguns are autoloaders. You ain't gonna be cycling the action at 350 fps...which kinda limits the use of such ammunition to single shot acts.

Some guns have been known to cycle even when the bullet gets stuck in the bore. I've seen it happen with a 380. I was reading about one 9mm pistol that did that on some forum recently. Can't remember where.
 
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