Lethality of 9mm FMJ at very low velocity?

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

It’s actually more than that, 1.44 ft/lbs but still a tiny number. IIRC I read somewhere BB guns cause around 4 deaths a year. “BB gun” covers a lot of ground though. There have also been people killed by just compressed air alone, no projectile at all.
 
What is the velocity of a bullet falling back to earth after being shot vertically? I’m thinking it’s about 350fps but not sure

I’ve read that people have been killed that way. I know that the roofs of buildings get punctured every New Years by stray bullets fired into the sky. If it will penetrate a roof I’m certain it could kill a human
 
Thanks for the responses. I will go with my initial assessment that such a projectile is potentially lethal based on the velocity determined after penetration of the building materials.
 
What is the velocity of a bullet falling back to earth after being shot vertically? I’m thinking it’s about 350fps but not sure

I’ve read that people have been killed that way. I know that the roofs of buildings get punctured every New Years by stray bullets fired into the sky. If it will penetrate a roof I’m certain it could kill a human
Well yeah, but the OP was asking about a 124 gr 9mm bullet. A 500 gr .45 caliber bullet fired in the air from my Sharps will reach approximately the same terminal velocity as a 124 gr 9mm bullet as it falls back to earth. But it will be a lot more capable of penetrating a roof or human skull.
I'm not saying a 124 gr 9mm bullet at 350fps is incapable of penetrating a human skull. I'm just saying that all of the studies I've looked up through Google searches about bullets falling back to earth and killing people didn't list the bullet weights.:)
 
A true story that is mostly meaningless.

One Sunday morning we got a call of a shooting victim at a hospital. Sure enough when we got there a young girl had a bullet lodged in the heal of her ankle. The X-ray clearly showed a undeformed 9mm bullet in her heel. She had minor pain for the wound.

The story we got was she was sleeping in the front bedroom when the house was shot at in drive by during the night. One of bullets penetrated through the exterior wall and hit her in the foot. Her Grandmother told her not to worry about it and put a bandaid over the entrance hole. The Grandmother then brought her to the hospital in the morning to be treated. Grandmother said she did not report it when it happened as she knew the Police would be at the house for the rest of the night and no one would get any sleep. She said she didn’t see the shooters so she knew they would not be caught.

The bullet was removed in the E.R., she got a some stitches and sent home.

So the bullet probably traveled 25 yards, completely penetrated the exterior wall of a wood frame house and made a wound so minor that the bleeding was stopped by a bandaid.
 
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?
I've witnessed my friend shooting a 5 gallon bucket with a 25acp. It ricocheted and hit him in the leg.
You still couldn't get me to stand in front of one willingly.
I think the 9mm at that velocity is in the same ballpark.
 
There is a long-held (but minimally supported) belief that the threshold of lethality is 60 foot-pounds of energy. If we accept that, then a load yielding less would not be expected to be lethal. That doesn't mean it can't kill; just that the likelihood of it causing death is minimal. Still, shoot someone with a 45 foot-pound load and you have still shot someone with a pistol and you can expect to be charged as if you were using a full power cartridge. Your defense attorney can raise the question of velocity, muzzle velocity and "technically" non-lethal energy. Hopefully the jury will buy it.
 
Still, shoot someone with a 45 foot-pound load and you have still shot someone with a pistol and you can expect to be charged as if you were using a full power cartridge. Your defense attorney can raise the question of velocity, muzzle velocity and "technically" non-lethal energy. Hopefully the jury will buy it.

And the relevance of this to the discussion is ??????
 
Just chipping in a little food for thought:
Ever see a wicked bruise from a paintball? They are capped (at official fields, anyway) at 300 fps and usually considerably slower by the time they hit someone.
They are .68 caliber (17.27mm) and average 3.2 grams (49gr).
In other words, 250% the diameter--a LOT more relative surface area I'm too tired to calculate--and 40% the weight of a 124gr bullet. And they're designed to deform, break, and disperse their energy. They can still leave a nasty bruise and occasionally a bleeding welt on skin that is bare or covered by a T-shirt or even denim. Players commonly wear an extra pair of strategically positioned socks if they don't have a cup, and those masks science fiction movies love to stick on future-soldiers aren't just to keep the sun off.
So a much smaller, much heavier, metal projectile?
Deadly? Maybe not, statistically. Dangerous enough? You betcha.
 
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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.

And where did you find one in stock? I have not seen one available in years.
 
I think everyone assumed you were talking about lethality on humans, although, to be fair, you didn't actually say that. If you were, legalities would be relevant.

I am talking about lethality on humans. As stated, the context is the residual velocity/energy of a projectile after penetrating building materials and the potential lethality threat.

This is NOT a discussion of merits of trying to create some non-lethal downloaded 9mm loading for defense, despite the "contributions" of people who don't read the posts.
 
You might check with the guys at the Box O' Truth. I don't see where they specifically tested a 9mm through enough wall sections to slow it down to 350 fps. but they might be interested in doing the work for you.
 
You might check with the guys at the Box O' Truth. I don't see where they specifically tested a 9mm through enough wall sections to slow it down to 350 fps. but they might be interested in doing the work for you.

I already did the testing that resulted in the 350 fps residual velocity. We didn't, however, do anything besides running a Phantom to get exit velocity, and just had sand for a bullet trap- no gelatin.

No offense, but from what I have seen of the "Box O' Truth" testing does not inspire much confidence in anything they produce.
 
I read somewhere that the Derringer gun John Wilkes Booth used to assassinate Abraham Lincoln was a one oz .44 caliber bullet with a 2.5 inch barrel. The said muzzle was 200 fps. I suspect getting shot in the head with 9 mm traveling at 350 fps would or could be deadly.
 
The BP deringer comparison is appropriate.

Booth got very adequate performance out of his pistol which featured a 130ish grain lead ball at 400ish fps, including skull penetration and almost full cranial traverse. It seems that a pointy 9mm fmj at 350 fps could do pretty much the same.
 
Don't get your response. I staff a level 1 trauma center and treat 150 gsw patients each year.. penetration kills.

I wrote a very snarky response first and then deleted it in the spirit of THR.

Did you read this thread?

The sole scientific purpose was to discuss the potential lethality of a 124 gr 9mm FMJ that penetrated building materials (think wall) with a residual velocity of 350 fps.

The topic is not what load is best for defense, or any variation of that theme.
 
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