A Medical Perspective On Ammunition And Lethality

A Medical Perspective On Ammunition And Lethality

A look at a medical expert’s perspective on ammunition and lethality in relation to bullet caliber, weight, velocity and projectile type.

“Kids in school are learning boater safety and not bleeding control.”

I chuckled a bit as I listened to Lindsay Gietzen explain the absurdity of today’s education system that often emphasizes denial and shameless propaganda.

“They act like we live in a world without two, maybe three guns per individual. Violence rarely waits for politics, and the fact is education is politicizing the need for emergency care by way of denying reality. People get shot, and wishful thinking won’t stitch up those wounds.”

Knives and bullets do very different things to the body, but the end result is the same. Blood loss from gunshots or stabs are treated the same way for the most part. The bullet is a fully expanded all-copper .45 ACP Barnes and the knife is an AMTAC Northman.

Gietzen is a person of incredible experience and equal amounts of sharp wit; the combination of those qualities makes her one of the world’s leading experts and educators on traumatic injury care. She’s seen thousands of gunshot injuries in the worst part of Michigan and is now doing her best to get tourniquets and bleeding control kits right next to AED machines on the wall of every building.

The revelations here may surprise you, and perhaps you’ll buy your own bleeding control kit after reading this.

How Bullets Kill

A gun needs to be two simple things: reliable and reliable again—everything else coming in order of personal preference. Accuracy comes with practice and cosmetic choices are largely irrelevant, so as a baseline, the gun must function. Now what about bullets?

A good question to ask is, why there isn’t as much of an emphasis on reliable bullets? After all, the bullet is what matters most. There’s a tremendous amount of science that goes into creating more advanced projectiles that guarantee superior performance.

“What causes death isn’t really kinetic force or expansion,” said Gietzen. “What causes death is rapid exsanguination (blood loss). A hit to the central nervous system or head does not guarantee an instantaneous kill. Despite what you see in the movies, the survival rate for wounds to extremities is very high, and death becomes more likely the closer you get to the heart of major arteries. The most deadly places to hit are the groin, armpits or a major artery in the torso.”

Bullet construction has improved in recent years, and small-caliber rounds, like the 147-grain 9mm above, are tough and offer great expansion … but they’re still prone to failure and clogging. This bullet was fired into gel.

So, what then constitutes an effective bullet?

“There’s nothing that says that a bullet that passes through-and-through is more deadly,” added Gietzen. “It’s also untrue that it causes more bleeding, because it’s all one wound. As for bullets that remain in the body, we end up leaving them in many cases.”

Gietzen continued: “When it comes to multiple injuries, there’s no real case that says more bullet holes in more places cause more bleeding. In fact, even a person shot once may not bleed externally. Almost all the blood in the body can be held in the pelvis, and it’s not uncommon for a gunshot victim to bleed externally in a way that does not appear to be life threatening.”

A healthy person can lose up to 40 percent of their blood and survive. There’s no set method to deprive a person of 41 percent, nor is there a means to predict what’ll happen when larger or smaller individuals are shot. In humans, damage a bullet does is often less related to velocity or mass, but rather the immediate aftermath and medical treatment given.

In a mass causality event, shooters often use rifles. It should be noted that at Columbine there wasn’t an AR-15 or AK-47 used: It was pistol-caliber guns and a shotgun. The Virginia Tech shooting was carried out with two pistols, a .22 LR and a 9mm. That shooting left 32 dead and 17 injured by shooting. In these mass casualty events, it’s not necessarily the initial injury that kills on contact, but the response time to care and neutralizing the threat so help can arrive.

Rifle bullets, in this case a Sig Sauer Elite Hunter .300 Blackout, have come a long ways as far as delivering consistent performance. Maintaining accuracy while offering a mechanically complex expanding bullet is no easy task, especially at the slower speeds of the .300 BLK. Is it more lethal than a FMJ? Hard to say since the use of expanding bullets in warfare isn’t widespread.

“When we have a victim brought in, we often don’t immediately know what they’ve been shot with … or even how many times they’ve been shot,” said Gietzen. “We find the most severe injures and begin treating those first. And not every hospital is equipped to deal with gunshot injuries. Bleeding control is being heavily pushed in the medical community, this being tourniquet application and wound packing. Stop that bleeding and the survival rate goes way up.”

How important is knowing bleeding control skills in these situations? Gietzen sent me documentation from the Berkley et al Journal of Trauma, 2008, which stated that in modern combat in Iraq, four out of seven deaths might have been prevented with early tourniquet use. It also stated that 57 percent of deaths in general would be preventable with early bleeding control and tourniquet use.

Calibers and Effectiveness

So, why does all this matter to the average CCW citizen, and how should it affect their decisions on which bullets to load … and what trauma gear to have close at hand?

In the weeks leading up to the writing of this article, I spoke to several medical staff who worked post-mortem. Those individuals chose to remain anonymous, but their information was somewhat inconclusive in terms of what calibers were more effective. It should be noted that not all bullets are recovered, and aside from law enforcement, where the number and location of shots fired is recorded in reference to a duty weapon, there isn’t a tremendously detailed picture of the answer.


The general (and predictable) consensus was that the most common CCW calibers see the most action. They all agreed that, from a medical perspective, there was no noticeable or real-world difference between .380 ACP, .38 Special, .357 Magnum and 40-caliber.

The only major standout was .45 ACP, where it resulted in about twice the fatality rate as the others, even to extremities.

Very little relevant information was available on .22 LR, .25 ACP or larger rounds like the .44 Magnum, simply because these are rarer selections for concealed carry.

There was no positive correlation with death based on bullet type used. Said another way, again from this medical perspective, hollow-points aren’t any more effective in practical applications than a FMJ. Of note is the Black Hills HoneyBadger line, which features solid, non-expanding bullets designed to cause more tissue damage (bleeding) by means of fluid dynamics due to bullet rotation, thus making them barrier-blind as long as the bullet is spinning.

The Black Hills HoneyBadger line features monolithic bullets with flutes to create tissue disturbances (tearing and penetration injuries) as a function of rotation alone. This means there’s no mechanical expansion to get results and no clogged hollow points. These bullets can reach just about any vital area from any angle and have a weight retention, even through glass and barriers, usually at 100 percent.

These numbers were quite similar to the 2018 study exhaustively titled, “The Association of Firearm Caliber With Likelihood of Death From Gunshot Injury in Criminal Assaults,” which determined that larger caliber guns were more likely to inflict death.

Overall, this study, while including a large sample group, was realistically and fundamentally flawed in that it grouped a wide number of calibers into seemingly random clusters, even grouping .45 ACP with 7.62x39mm! It rated large bullets (irrespective of speed or weight, a .45 ACP is typically a 230-grain bullet at 850 fps and a 7.62 is a 123-grain bullet at 2,400 fps) as 4.5 times more likely to kill than with smaller calibers.

But again, the conclusion is noteworthy in that larger caliber guns were more likely to inflict death.

This beautiful expanded all-copper .45 ACP bullet was fired into gel. In real life, it’s rare to get a perfect and symmetrical expansion like this, which makes it difficult to establish a true gauge of effectiveness when even a T-shirt can impede it. The .45 ACP has never struggled, even in hardball form, and complexity isn’t always warranted when a simple 230-grain FMJ will get the job done just as well now as 100 years ago.

Do Bullet Types Even Matter?

It’s my belief, based on my experience and that of professionals far smarter than me, that most bullet designs have less bearing on lethality than where that bullet goes. Shot placement, not caliber used or bullet type used, is the major deciding factor in lethality. This might be a no-brainer, but there is no doubt that the merits of bullet type will be debated for years to come.

In the meantime, take a bleeding control class. Should the worst happen, it will likely be far more useful than deciding between 9mm and .45 ACP.

About The Expert:

Lindsay Gietzen is a professor and program director at one of the top research universities in the world, where she specializes in simulation and educational evaluation. She’s also the co-director of the AVERT program for the Health and Safety Institute. 

As a physician’s assistant, she practiced in emergency/trauma medicine in Detroit, Michigan, and then specialized in neurological surgery, leading a team that developed and performed many procedures for the first time in the United States.

She’s a member of the Michigan Academy of Physician Assistants, American Academy of Physician Assistants, Physician Assistant Education Association, and Director at Large of the Association of Neurosurgical Physician Assistants.

Gietzen is currently serving an appointment to the American Council on Education, where she’s an expert faculty evaluator for military medical programs.

Editor's Note: This article originally appeared in the 2021 CCW special issue of Gun Digest the Magazine.

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  1. Bleeding kills. That is a fact. And a real big thumbs up to the author.

    But the discussion regarding bullets is really lacking in substance and motivation. Basically she says they all fall to hardball. End of discussion. Mind you, 45 hardball 🙂

  2. Her comments about a .45 being 4 times more lethal than a .40 or .357 simply doesn’t match with the statistics provided elsewhere. It’s pretty clear without any expertise that delayed treatment particularly delays in stopping the bleed is going to result in more deaths.

  3. Good article but lack clarity regarding what is considered large caliber. In the second study she refered to, where large calibers were 4.5 time more deadly, the categories were : small (22, 25, 32), medium (38, 380, 9 mm) and large (357 Mag, 40, 10 mm, 44 Mag, 45 ACP, 7.62×39). The study is “The Association of Firearm Caliber With Likelihood of Death From Gunshot Injury in Criminal Assaults”, published on July 27th 2018.

  4. In light of her quote “in these mass casualty events, it’s not necessarily the initial injury that kills on contact, but the response time to care and neutralizing the threat so help can arrive” how can we evaluate the decision to delay at the Uvalde event?


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