9mm Ammo

Am Shooting Journal ^ | 12/18/2018 | J Johnston

[w1n1]

When I worked at a gun store I was frequently asked what caliber was best for any given situation. It would have been nice if there had been some sort of magic death ray that I could have suggested, but there isn't, and most people have a pretty flawed understanding of what actually happens when a bullet interacts with a human target.
For starters let's examine a couple of concepts that don’t actually exist in the scientific world but everyone talks about anyway. I'm going to regurgitate the work from those better than myself, and the information is worth paying attention to.

KNOCKDOWN POWER
This doesn’t actually exist. If a bullet had enough force to knock down an individual, it would also knock down the individual firing the gun. People do not go flying through the air when hit by a bullet, contrary to what the movies and television would have us believe. Newton's Third Law and all.

ENERGY DUMP
On the back of a box of ammo, manufacturers list the foot-pounds of energy (ft-lbf, or foot-pounds of force/energy) that their rounds have. Well, that doesn’t actually matter. The terminal performance of a projectile is determined solely by how much tissue it cuts, crushes or tears. While it has been advocated by many-a-misinformed-gun-counter commando that some sort of energy transfer occurs between a projectile and its target, this has been rejected by everyone I respect who studies terminal ballistics for a living. Read the rest of 9mm ammo.

[CheneyClone]

As my rifle instructor told me, you don’t aim a shotgun, you point it.

[Carriage Hill]

Liberty Ammo is amazing. I use it for my daily carry 1911 .45cal ACP Kimbers.

https://libertyammo.com

[Carriage Hill]

Liberty ammo:

https://libertyammo.com

[rjsimmon]

I’ve seen the 9mm and the .45 used in combat - the .45 was a killer, the 9mm was a wounder.

Absolutely concur! Stopping power is real and I too have seen it. I have seen a .45 pick a man up off of the ground. As well I have seen 9mm go right through a body.

[Tijeras_Slim]

Shot placement is King, adequate penetration is Queen, and everything else is angels dancing on the head of a pin.

[AlaskaErik]

I definitely agree with him when it comes to revolvers. No way am I betting my life on something that only has five or six rounds. Because once those five or six rounds are gone, you're out of the fight and most likely will never have time to reload before the fight is over.

I carry a Glock 23, but if I was buying a defensive pistol today, I would go with the Glock 19. 9mm ammo has definitely improved over the years.

[Bonemaker]

[Bonemaker]

“While it has been advocated by many-a-misinformed-gun-counter commando that some sort of energy transfer occurs between a projectile and its target, this has been rejected by everyone I respect who studies terminal ballistics for a living. “

Oh really? Then what happens to the energy?

[CommerceComet]

As my rifle instructor told me, you don’t aim a shotgun, you point it.

One thing that everyone understands is that if you are staring at the business end of a shotgun at close range, the marksmanship of the shooter isn't a big factor. The shooter has a really big margin of error and a right-thinking human will not like the odds.

[Delta 21]

Damn watermellons!!

[redfreedom]

And 5 inch naval shells from the USS McCormick were used to save our a$$es back in 69. But the racket from those guns were nothing to the stunt the Navy pulled one totally dark night while I was on the perimeter, near asleep. It was the loudest explosion I heard over there. I found out the next day the Navy floated an 8 inch gun into the harbor and fired it. Talk about events that give a person an exaggerated startle response!

I see your point. Clark Kent hitting anther person at twice the speed of a bullet would be similar to a bug hitting a windshield, with that other person doing the splattering.

[Paal Gulli]

I am bumfuzzled that the only firearm blog that has any significant replication at all on Free Republic also happens to be one of the lamest. If I were conspiratorially-minded, I might think that ASJ has people on the payroll who are posting for them.

Case in point:

"KNOCKDOWN POWER

This doesn’t actually exist. If a bullet had enough force to knock down an individual, it would also knock down the individual firing the gun...."

Bullcrap. One of the most common "myths" alleging to refute "knockdown power" and it's a complete misunderstanding and misapplication of Newton's second law of motion. Somebody with no understanding of the laws of physics parroting something he (errantly) thinks is clever.

Force = mass x acceleration

... and ...

acceleration = final velocity minus initial velocity divided by elapsed time

... therefore ...

Force = (mass x Δv)/Δt

... so ...

Provided mass remains constant, Force changes inversely with elapsed time

Which means -- and despite all the misinterpretations -- the forces at either end DO NOT HAVE TO BE EQUAL and will tend to be higher on whichever end has the briefer period of acceleration.

No matter how many parrots claim otherwise, nothing in Newton's 2nd states that "If a bullet had enough force to knock down an individual, it would also knock down the individual firing the gun." In fact, it states exactly the opposite. Force must vary inversely with the acceleration interval. Which means it is possible -- both in theory and in practice -- for the target to receive more "force" (in the classic sense) than was delivered by the firearm to the shooter. Much more in fact.

If I were to shoot someone wearing Level IV body armor (with SAPI) from a range of one inch (1") with an M4 carbine, the bullet would strike the SAPI with near as makes no difference the exact same velocity as it had at muzzle exit. Therefore bullet mass, V2 and V1 all are (virtually) the same at both ends. But what changes is acceleration.

The bullet at firing would accelerate over a distance of slightly less than 13" but it would de-accelerate to a complete stop in a distance of less than an inch. Since final velocity at the firing end approximates initial velocity at the target end, the force received by the target (ignoring the effects of ejected propellant gasses) would be 13 times(-ish) greater than that created at the shooter's end.

Even ignoring body armor, a human torso is about a foot thick, so provided the bullet was fired from a barrel significantly longer than 12", and provided the bullet looses all velocity and remains within the target, and ignoring the decay in bullet velocity while it is in flight, the target will always receive more force than was delivered to the shooter.

Granted it's something of a moot point to a discussion of the 9mm cartridge since few handguns have a barrel of more than 12", but my point is that anyone who flaunts his ignorance of Newton as means of bolstering the reader's impression of his firearms "expertise" isn't to be trusted on either count.

So popular myth notwithstanding, it is quite possible to build a handheld gun that is capable of physically knocking a man off his feet. But that would require an exceedingly long acceleration interval, which translates to a exceedingly long barrel, which would be too heavy and unwieldy to serve any practical use.

Possible? Yes. Practical? No.

[43north]

In theory, hollowpoints are great but that is only IF they expand. A 9mm is .355 caliber, and .45 is .451 caliber. Hollowpoints are available in both calibers. If they don’t expand, the .451 bullet always wins. I believe that hollowpoints don’t always expand.

[lapsus calami]

 

 

the .45 used in combat - the .45 was a killer

 

A friend of mine attested to that. It was him versus 4 of the German Wehrmacht in heavy winter clothing at close range. He said they dropped like sacks of potatoes. He was deep in the s*** at the time - expended all ammo of available heavy weapons and other small arms, anything else that could have been of use was on fire, his AO was overrun by German troops, his unit was scattered and isolated - like he was - and he was down to a 1911A1 with two spare magazines and a bayonet. Not sure why they didn't shoot him outright. Maybe since he was an officer they were trying to capture him instead. They had bayonets fixed on their K98s, probably thought they were going to corner him and get a surrender that way. Or else maybe they were out of ammo too. He didn't have time to check their weapons out of curiosity, just shoot & scoot the hell out of there.

 

 

[Big Red Badger]

4 against 1,,
Fair Fight.
American, you Know.

[gundog]

Yup. I like finding a little bald spot on the downrange side, where the bullet came to rest under the hide. Don’t need a bloodtrail when they’re dead in their tracks.

[Pollster1]

https://www.buckeyefirearms.org/alternate-look-handgun-stopping-power

The bottom line: Hit the bad guys with a rifle or shotgun if possible. If not, hit them with almost anything. For handguns calibers, most of the difference in effectiveness comes from differences in accuracy, not differences in inherent effectiveness. The .44 magnum may "blow your head clean off", but the .22 is even more likely to get a one-shot stop. My dad shifted to the .22 as he got older. He could still hit with that even as his strength faded, so that was the right caliber for him.

[Noamie]

65% of people shot with a pistol/revolver survive. Pistols suck at killing people. Shotguns have limited ammo, tight patterns at short ranges, and many are slow to reload.

That being said, the best weapon and caliber is the one in your hand. Everything else is moot.

[LumberJack53213]

My dad used to hunt with a .22 rifle for whitetail deer, got a deer every fall

[dangerdoc]

At some point energy becomes important. You have to be lucky to survive a torso hit with a low energy rifle round like the .223 and pretty unlikely to die from the same hit with an air rifle. Pistols are somewhere in between.

I suspect a hit with a well constructed .357 mag does something different that a well constructed .380.