Can a small caliber be as powerful as a big one?

[Derringeer]

Hello. If two barrels of the same length where loaded with the same amount of powder and with projectiles of the same weight, but of different calibers, will then the stopping power of the guns be equivalent?

I made a picture just to clarify what I mean https://imgur.com/a/yvu6cns

[burrhead]

F=ma where "F" is Force, "m" is mass, and "a" is acceleration. Caliber doesn't have anything to do with it. This would be at the muzzle. A .22 projectile with a mass of 100gr will have a better BC than one in .40 so the .40 will shed speed faster over distance.

[Lohman446]

Stopping power is an ill defined term. Energy will be virtually equal at least at the end of the barrel as the two factors involved in energy are mass and velocity. The smaller projectile will, at least in theory, have better sectional density and less air resistance enabling it to maintain velocity longer. The larger projectile will create a bigger hole on impact which may be important but not likely.

In the end I expect all the differences (outside of making arguments of extreme) will be fairly meaningless in terms of stopping power.

Edit: There are some interesting things here though. The larger circumference will have more drag in the barrel. I'm not sure how much of a difference its going to make but I would not rule out the idea that it could be substantial. We are getting into an area of physics here that I am passingly familiar with but by no means familiar enough to really calculate it out

[DaleA]

I'll play.
Note: if you're still using an outdated, old fashion, browser (like I am, Internet Explorer that came with Windows 8.1) you aren't going to see the nifty diagram the OP included. Use a modern browser like Chrome and you'll be fine.

Okay "stopping power", right there may cause some "discussion" but I'll leave that to others.

The projectiles are the same weight, just different diameters. Do we assume they are the same length? That might be done if they are made of different weight metals. Does that even matter? Wiser folk than I may chime in on this.
Also is this material designed to expand on impact? Inquiring minds might want to know.

All in all I suspect the smaller diameter projectile will penetrate more deeply but that does NOT mean it will be more effective in stopping someone.

As many folk will undoubtedly say shot placement is probably the over riding consideration. That is, a little bitty round to the right spot will trump a big old round to a non-critical part of the body.

In short (yeah I know that boat already sailed) not necessarily.

Note: Somebody on this site has a sig line "All else being equal (and it almost never is) bigger bullets tend to work better" and they generally know of which they speak.

[ms6852]

I do not think so. But I love the question. My reason for the answer has no sound scientific background or a physics background but what I consider to be for me common sense.

As Lohman446 stated "stopping power" is an ill defined term and miss used throughout the shooting sports world, because as we know that a 22lr can cause fatal wounds as well as a .45 caliber. Been all equal with barrel length, mass and powder except diameter the two rounds could be matched ballistically in velocity and muzzle energy but the density of the larger diameter bullet will never be equal to that of the smaller caliber round. The smaller caliber will be longer to account for the weight required to match the larger caliber, but will be lacking the hydrostatic shock the larger caliber round has. It's like shooting an arrow. Will the arrow kill the deer yes it will, can both rounds kill the deer as you described yes, but which will do it more efficient provided all is equal like shot placement. I believe the larger caliber will be more efficient.

[Double Naught Spy]

but will be lacking the hydrostatic shock the larger caliber round has.

Speaking of misused and misunderstood terms...

So you are talking about when the two projectiles are impacting in excess of 2200 fps in order to actually cause potential hydrostatic shock, right? Hydrostatic shock itself, the remote wounding of neural centers, doesn't always even occur with larger calibers that are traveling at sufficient velocity to be able to cause it.

[Scorch]

"Stopping power", if it does exist, is affected by caliber. Taylor's KO charts, for example, gave better "stopping power" (KO values) to larger diameter bullets. Makes sense, if you think about it: with a given amount of energy, the larger frontal area of the larger caliber projectile will deliver more energy and penetrate less as it strikes a soft target, the smaller diameter projectile will deliver less energy and penetrate deeper. Kind of the "5.56 vs 7.62" internet argument you see a lot of.

"Hydrostatic shock" is mainly a function of velocity, so perhaps a smaller diameter projectile would have an advantage since it does not slow as quickly. I don't know about that one, I would have to think about it for a while.

[Ruger45LC]

The performance would differ, the .40 could be considered deadlier because it pokes a bigger hole but a .22 100gr would have much higher sectional density than a .40 100gr, so it would definitely penetrate deeper. Their "energy" might be the same, but I'm not a big fan of relying on energy to determine effectiveness.

[Bill DeShivs]

Bigger bullets kill you deader than small ones.

[pwc]

Effective; no.....deadly; can be

[TXAZ]

The only difference here is the 100gr of lead in each bullet is in a slightly different shape per the OP diagram, .22" diameter and longer for one, and .40" diameter and about 1/3 the length of the .22 round.
With the same bullet mass and powder in an ideal situation as is assumed by the OP means the same muzzle energy and muzzle velocity. (Again, the only difference here is in one case the 100gr bullet is .22" in diameter (the longer bullet) and the other is .40" diameter (the shorter fatter bullet). That means it's all the biomechanics of instantaneous trauma. For equal energy on impact of a body, the smaller diameter bullet is going deeper because it has less frontal area to slow it down. If that's the difference the answer is going to be did the person shot get hit in the gluteus maximus or 'credit card'(between the eyes)?
I expect the .22 will more lethally penetrate the credit card than the .40 round solely because of the 3.3 times higher pressure created by the .22 than the .40 better punching through the skull. In the gluteus, I would expect 'wider damage' by the .40 but deeper damage by the .22.

[JohnKSa]

...will then the stopping power of the guns be equivalent?

What is "stopping power"?

[Double Naught Spy]

The performance would differ, the .40 could be considered deadlier because it pokes a bigger hole but a .22 100gr would have much higher sectional density than a .40 100gr, so it would definitely penetrate deeper. Their "energy" might be the same, but I'm not a big fan of relying on energy to determine effectiveness.

I assume are talking about 2 projectiles traveling at the same velocity?

Sectional density is directional. The 100 gr. .22 may have a higher section density and penetrate deeper, IF it remains stable and does not tumble, if the bullet stays intact.

Sectional density relative to penetration is another one of those sort of misleading variables that sometimes we put more stock into than we should. You can have two bullets with virtually the same sectional density, but different construction such that one disintegrates on impact and one that stays together and hence have two very different amounts of penetration.

[dyl]

At some point, you'd have to deal with that elephant of a question: what is stopping power? - in order to answer the original question. Regardless of round characteristics, the properties of the target make a big difference. For thick skinned animals, I've heard that hard cast lead with a focus on penetration is the way to go. I've read that people can be more sensitive to pain, but in certain circumstances don't even know they've been shot. The discussion about bullet weight and surface area / sectional density inside the barrel is analogous to hollow point vs. FMJ or flat nose design.

As it stands I'm assuming the original question about stopping power is related to stopping a human assailant, with the broad definition of "making them stop being a threat". Unless someone gives a more specific requirement, the answer will be a big "it depends". Pain compliance? Central nervous system hit? Blood loss / loss of consciousness?

• shot placement is most important for effect
• a larger surface area can technically crush more tissue
• but a larger caliber round means less capacity, slower follow-up shots for the same accuracy

I'd say that if we remove hollow points from the equation that purposely stop short in tissue, most calibers from 9mm and larger in an FMJ or Flat nose are *more* than adequate to penetrate through a person if we also remove bones and clothing / armor / limbs from the scenario. But in reality, you can't remove these things: rib cage, cranium, angles, moving targets. In a rifle with enough velocity and heavy enough bullet, these things have less impact on the trajectory. But on a handgun you never know where the round will go. So you'd have to specify more requirements to get a more specific answer.

[CDW4ME]

I'll use my chrono averages and KE to compare power, all Federal HST.
Glock 32 (357 Sig): Federal HST 125 gr. @ 1,358 fps / 512# KE
Glock 23 (40 S&W): Federal HST 180 gr. @ 1003 fps / 402# KE
Glock 21 (45 acp): Federal HST 230 gr. @ 863 fps / 380# KE

In this comparison the smaller caliber (357 Sig) produces more KE (power) than the larger calibers.
Whether 357 Sig has better "stopping power" ... lets call it incapacitation potential than 45 acp is debatable.

However, given equal shot placement, lets get that disclaimer out of the way ...
Its not debatable that any of those calibers have better incapacitation potential than 380 or less.

[Nathan]

Hello. If two barrels of the same length where loaded with the same amount of powder and with projectiles of the same weight, but of different calibers, will then the stopping power of the guns be equivalent?

Factors....
same powder charge
Same length barrel
Different bore diameters
Same bullet weight

The larger bore will have a larger velocity.....but the smaller bore could have a higher bc. It depends on too many other factors to be sure. It will likely be about the same, so the larger one has a significant advantage due to same bc and higher velocity.

Stopping Power - For this, stopping power has to be defined. I would define it as the energy expended in the animal through expansion and tissue damage.

The larger caliber will have more velocity meaning higher kinetic energy at impact. Assuming same bullet construction, the larger diameter will expand easier due to frontal area. This too is a win for the larger caliber.


Answer: Caliber wins! This comes at a price......more recoil!

[Cosmodragoon]

I'm rusty on my physics but let's think about the diagram. You've got the same mass projectile, the same powder, and the same barrel length. The main change is the diameter.

Assuming decent rifling and the smaller caliber doesn't keyhole, it will have greater sectional density and theoretically better penetration. It could tumble after it enters but that could be a good thing for "stopping power". (I translate that loosely as the chance of doing damage sufficient to render an animal immobile or incapable of attacking.)

Assuming the same, the larger caliber should at least make a bigger hole.

One last question is how the volume change in the barrel will affect expanding gasses behind the projectile. I'll leave that for someone smart to answer. =P

[T. O'Heir]

Neither a gun nor a cartridge has "stopping power". Physics doesn't allow it.
"...the same amount of powder..." Which powder will matter.
"...larger bore will have a larger velocity..." Not necessarily.
The issue here is the lack of comparable data. As in like bullet weights, powders and barrel lengths in 2 chamberings. There are no 100 grain .22 handgun bullets and very few if any .22 100 grain rifle bullets. No data for 'em anyway.
"...a higher BC..." That doesn't matter. Ballistic Coefficient is about how a bullet travels through the air. Has nothing to do with anything else.

[44 AMP]

. If two barrels of the same length where loaded with the same amount of powder and with projectiles of the same weight, but of different calibers, will then the stopping power of the guns be equivalent?

No.

The main reason being that "stopping power" is an unquantifiable thing. The "best" theories are not able to consistently predict and are only rough approximations of SOME observed behavior.

There is no math formula that gives any kind of reliable numbers for "stopping power" simply because EVERY case can have differing, often hugely differing factors.

People often use energy figures as indicators of "stopping power" but that is a flawed assumption as well.. Energy numbers are a math calculation, and DO provide a consistent medium for comparison between dis-similar calibers but are not valid regarding "stopping power" because nothing really is.

Consider this, just as an example.
You can load a .22-250 and a .45-70 to identical energy levels (ft/lbs).

Energy (alone) says they are equal. Both will certainly kill, but which one would you choose to stop an 800lb angry beast who wanted very seriously to stomp you to bits??

Every animal is different, every person is different, every SHOT is different. Often the differences are small and unnoticed. Sometimes they are large and the determining factors.

There is an old African saying that goes something like this...
"one day, you meet a lion on the trail, and he runs away...
The next day, you meet his brother, and your family wonders why you did not come home for dinner...."

Your example of equal weight bullets with equal powder pushing them only difference being diameter will give equal results using math, but CAN show vastly different results in the field due to all the other factors involved.

My signature line is what I have personally seen. I hold it to be essentially true.

[Pond, James Pond]

Edit: There are some interesting things here though. The larger circumference will have more drag in the barrel.

Wouldn’t the narrower, longer bullet have more surface area in contact with the bore?

[44 AMP]

Wouldn’t the narrower, longer bullet have more surface area in contact with the bore?

aargh..10grade geometry AGAIN

No, I'm not doing it for you!

look up how to calculate the surface area of a cylinder.

you'll need to know the length and the diameter but after that its just math..

good luck!

[tipoc]

Hello. If two barrels of the same length where loaded with the same amount of powder and with projectiles of the same weight, but of different calibers, will then the stopping power of the guns be equivalent?

Ok the actual problem is that we have a handgun round (5" barrel) and a 22 caliber bullet and a 40 caliber bullet, both 100 grs. and both cases loaded with 25 grains of an unnamed smokeless powder.

So we don't know how fast these theoretical bullets are going. Without that piece of information most calculations are, well sorta fantasy land.

A 100 gr. 22 caliber handgun bullet comes from what round? Not a 22 magnum or 22 lr. What 100 gr. 22 caliber bullet comes from a 5" barrel?

I'm no expert but what charge of 25 gr.s of powder gets a 40 caliber bullet going at what velocity from a 5" barrel? It will not be hitting the same velocity as the 22 backed by 25 grs. 25 grains of powder in a rimfire round?

What cases are we speaking of? Is the 22 coming from a necked down bottlenecked case? or a straight walled?

The question is so general, and unspecific (or too specific) I don't think any sort of useful reply can be made.

tipoc

[stinkeypete]

if we assume the density of the two projectiles can be different, it gets interesting. If we must use lead, not so much interesting.

If we take a .22 bullet and hammer it flat to make a .45 "slug" its gonna be like trying to shoot a foil disk and will just crumple and go "pffft"

if we take a .45 slug and make a .22 bullet out of it, it's gonna be a little arrow of lead and good luck getting that launched. Its too noodle like to fly or handle the torque of the rifling.. it will curly-cue or fall apart in the air.

But.. if we can adjust our density... interesting stuff!

[big al hunter]

Given the same powder charge in both barrels....the larger caliber will have less velocity because the powder has more volume of barrel to fill. Therefore generating less pressure. Lower velocity plus wider frontal surface area equals far less penetration. Depending on the target, this could be what changes the equation. Shallow penetration may not stop the target at all. Something to think about.

[ms6852]

All rounds regardless of caliber size, density are lethal. Many will state that a larger caliber makes a larger whole and will bleed faster. The statement is true, provided that you are accurate with a large caliber firearm. I have seen many instances where novice shooters are shooting basically portable canons and enjoyed themselves shooting it and other did not but a majority of them never hit their target. So what good is having a large caliber gun if you can not shoot it reliably. Just read an article where a boy was just recently killed with a BB gun, I wonder how much that BB will penetrate in a Gel Test. I think we we many times focus on to many issues that are not relevant when it comes to "stopping power" or which caliber is most powerful. Does not matter if you are thoroughly trained and maintain you shooting skill levels as it is a skill that diminishes quickly. Your brain is the most deadliest weapon you have....or the weakest link in your arsenal.
https://www.foxnews.com/us/florida-b...ot-with-bb-gun