Some data on the 9mm = 357 mag theory

Jayne

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The idea that a small 9mm auto is ballistically the same as a small 357 wheel gun has been floating around and proven or disproven, depending on who you believe. Several of us shot some rounds over a chrono today out of a small 357 (LCR) and a small 9mm (G43) just to collect data. The chrono was dropping some shots which is why we don't have 5 readings for all the rounds tested.

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If we use the G43 with the HST rounds as our baseline, full power 357 loads out of the snubby deliver 16-22% more power than the 9mm. That's not a whole lot more given the downsides of trying to hold on to the 357, but it's not exactly "the same" if you like math.

We did not have any 9mm +P to try, going to see if we can find some to see how it does vs. the Critical Defense in 357. I actually use 9mm CD, so I can chrono that as well.
 
That would be fun to shoot over a chrono and see how it does out of carry sized guns.
Friend of mine swears by it. Iā€™ve got a couple boxes but donā€™t presently carry it.
 
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I like math but choosing a semi over a revolver was an easy decision.

Math made bailing on .40 a slightly harder decision.
 
Never heard this. This is what 357SIG is all about. Why would they have made 357SIG if 9mm was in 357 magnum territory?

Testing them out of the shortest barrels possible works to reduce the difference, it's like a 10ft drag race between a corvette and a yugo, yeah the corvette will still win, but not by much.

Even 357SIG does not match 357 magnum with heavier bullets or out of long (carbine) barrels. You only have to compare case capacity to understand why.
 
This about sums it up? 3:38 "...among the common carry calibers, that there was not more difference." This is not a scientific test, but ok nonetheless. For me it comes down to concealability, comfortable carry, capacity and ease of reloading. Based on that, 9mm semi-autos win for me. My basic truck gun carries 15-17 + 1 with a few extra mags, and my carry gun 8 + 1 with extra mags.

 
Data collection should be extended to include longer barrels. The divergence will become apparent, and it will become clear that the barrel is the limiter.
 
Data collection should be extended to include longer barrels. The divergence will become apparent, and it will become clear that the barrel is the limiter.

some data is already in there, the 3.5" barreled gun is already up to 150% of the energy of the 9mm. But that's not the point of the comparison here which is small 9mm vs. small 357, we just threw that in there to verify that even slightly more barrel than a snubby starts to bring the 357 to life.
 
My "real life" stuff is based around the 2 guns my Bud and I used to shoot side by side. He was shooting a Beretta 92 in 9mm and I had a S&W 19 w/2.5" barrel. We shot a bunch of "stuff" and the 357 w/2.5" barrel consistently out performed his 9mm. I don't recall what load he was shooting but I had Rem 125gr JHP since I had an almost unlimited supply.
Our excursions included targets as well as a little Raccoon and Opossum sized game. It always seemed the 9mm required more than one shot whereas the 357 usually got it done with one shot. Ranges were almost always within 20 yards with very little if anything in the way.
With all of that said the muzzle blast was no comparison, the 357 was MUCH louder probably due to the barrel length.
 
For human sized targets, with modern bullet technology, using a 357 isn't going to noticeably help stop a person better than 9mm. The FBI and Federal Ammunition ballistics team have proven this time and again. Shot placement and modern bullet technology was what mattered the most. That said, the differences become more apparent when it comes to what the bullet has to go through before it reaches the person. The more powerful bullets do go through metal and glass better than 9mm.
 
Paul Harrell did a good video comparing these very calibers. There are many rational reasons to choose a semiautomatic 9mm for defense over the .357 magnum, but as far as I can tell raw power is not among them. Everything is a compromise.

 
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For human sized targets, with modern bullet technology, using a 357 isn't going to noticeably help stop a person better than 9mm. The FBI and Federal Ammunition ballistics team have proven this time and again. Shot placement and modern bullet technology was what mattered the most. That said, the differences become more apparent when it comes to what the bullet has to go through before it reaches the person. The more powerful bullets do go through metal and glass better than 9mm.

They haven't proven that at all. The FBI have come to the conclusion that 9mm is sufficient for their needs based on what evidence/data is available and their own testing. There are too many variables to say conclusively that 10-50% more energy doesn't stop a person better...how could it not? It is also very possible that modern technology hasn't yet been properly applied to make full use of that difference in energy.

And let's face it, while bullet technology has improved to a degree, 9mm in law enforcement and most defense applications still has the same bullet weights, operates in the same velocity ranges, and still relies on an expanding bullet. This isn't dramatically different than 30 years ago. The ammo companies have to say something to convince you to pay $1 per round of defensive handgun ammo. Is it true that modern 9mm bullet technology is all that or is it just marketing?

If anything, I think the science has simply helped disprove the myth that .45 and .40 were incredibly better manstoppers.
 
They haven't proven that at all. The FBI have come to the conclusion that 9mm is sufficient for their needs based on what evidence/data is available and their own testing. There are too many variables to say conclusively that 10-50% more energy doesn't stop a person better...how could it not? It is also very possible that modern technology hasn't yet been properly applied to make full use of that difference in energy.

And let's face it, while bullet technology has improved to a degree, 9mm in law enforcement and most defense applications still has the same bullet weights, operates in the same velocity ranges, and still relies on an expanding bullet. This isn't dramatically different than 30 years ago. The ammo companies have to say something to convince you to pay $1 per round of defensive handgun ammo. Is it true that modern 9mm bullet technology is all that or is it just marketing?

If anything, I think the science has simply helped disprove the myth that .45 and .40 were incredibly better manstoppers.
The conventional wisdom today (FBI included) is to consider visible tissue damage only - penetration depth and wound cavity width - the latter they pretty much say is negligible at pistol velocities regardless of caliber. Well I think that just might not be all that goes into a perp's decision to stop. Also, I wonder about their ability to even measure physical damage accurately if the measuring technique is visual.
 
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In a full size gun, I'll happily carry a 357. But in small CCW style pistols, I'm going for a 9mm. In a small gun, I'm willing to give up a little power to gain some mag capacity and a firearm that's generally easier to shoot.

In a full sized handgun, I'm a firm believer in the 357.
 
With a short barrel.....the difference isnt huge. I've had factory Winchester 9mm. 115 grain ammo that was 1400 fps from about a 4.5 inch barrel.

With magnum rounds that use a slower burning powder and a long barrel......the difference will be noticable. I shot some buffalo bore 125 grain that was 1630 fps from a 6 inch barrel.....thats stout for a handgun.

For a carry size gun.....not much difference.

H
 
The conventional wisdom today (FBI included) is to consider visible tissue damage only - penetration depth and wound cavity width - the latter they pretty much say is negligible at pistol velocities regardless of caliber. Well I think that just might not be all that goes into a perp's decision to stop. Also, I wonder about their ability to even measure physical damage accurately if the measuring technique is visual.

Good point. Current testing methods only provide a standard to measure against and are from accurate simulations of performance in humans.
 
Was that a fluke or does Winchester factory ammo typically go that fast?

Pretty sure it was a fluke. But you knew it was hot and the chronograph verified it. There is some reloading data that are consistent with it also. Winchester white box isnt always the most consistent ammo and this was probably around 2010-2012 when production was wide open........ammo was still within safe limits, bit you didnt know if you were buying 1100 or 1400 fps ammo. I also bought some Winchester 110 grain 357 magnum around the same time frame. That 357 had the most felt recoil from a 357 magnum I have ever felt......... I didnt have a chronograph at the time, but I think I still have a box and change of that stuff because I didnt want to finish it..... Maybe one day i will try it with the chronograph to get a number with a feel. I swear I could feel the bones in my forearms flexing.
 
What does this mean Jep???? What's he shot with it???
I hope not. I suspect he bought into the marketing hype over the extreme velocity. I bought into it ā€˜cause he said it was good stuff. :confused:
 
I hope not. I suspect he bought into the marketing hype over the extreme velocity. I bought into it ā€˜cause he said it was good stuff. :confused:
You're a good man Jep! Don't buy the hype. Ball in all will do anything you need. Remember handguns are pitiful. What they have going for them is portability. Penetration and Placement is all that matters. First you must get in to something that matters. Hydraulics or electrics. For that you need Deep penetration. All shots are Not frontal. Over penetration is a myth!!! It has happened so little as to not being able to figure a percentage. Also, newest criminal justice stats say up to 82% of shots fired by LE are "Air Balls". Which is worse an unfigurable chance of over penetration or a MISS!!??
Most autos will work with Ball. It's inexpensive and will give you the penetration you need. Go and Sin No More.
 
Hit the range and added more data to the chart. I had a box of Corbon 9mm 115gr +P dated from 1992 and we fired it through our test mule G43. 135% of our baseline, and higher than either of the full power 357 loads out of the LCR. That thing is moving and producing energy... and recoil... and lots of pressure signs on the brass. Flat primers, really nasty denting, etc. We agreed it's not worth the loss of control of the little gun just to get that extra oomph. The box says 1350 fps and we were getting that out of the G17 which has a 1/2" longer barrel that the corbon site says they test out of.

You'll see the same gun/ammo combo on there a few times, we shot some of the old combos from last time again to see how much of a variance there was between trips.

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Thanks for taking the time to do all of this.Being a Taurus nerd(let the shaming begin)I have never seen a Taurus 608 with less than a 4" barrel from the factory.
 
Thanks for taking the time to do all of this.Being a Taurus nerd(let the shaming begin)I have never seen a Taurus 608 with less than a 4" barrel from the factory.

It's the ported one, so we figured it's maybe 3.5" of actual and then the bit with the holes? We didn't want people with a proper 4" gun to feel like we were trying to be like them.

On the length topic, the autos include the whole chamber, the wheel guns do not, I've never understood why but I guess no one compares wheel guns to autos that way. Except we are.
 
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You're a good man Jep! Don't buy the hype. Ball in all will do anything you need. Remember handguns are pitiful. What they have going for them is portability. Penetration and Placement is all that matters. First you must get in to something that matters. Hydraulics or electrics. For that you need Deep penetration. All shots are Not frontal. Over penetration is a myth!!! It has happened so little as to not being able to figure a percentage. Also, newest criminal justice stats say up to 82% of shots fired by LE are "Air Balls". Which is worse an unfigurable chance of over penetration or a MISS!!??
Most autos will work with Ball. It's inexpensive and will give you the penetration you need. Go and Sin No More.
Its ball to the wall for me.

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At most self defense type handgun velocity range, fps doesn't matter as much as bullet design. There have been a number of studies, that say a bullet needs to be going 2000-2200 fps at impact to surpassed the elasticity capability of human tissue .
 
Theories are cool and all, but what's more important to me, is what actually works on the street? There's good historical data out there. There was that thread a few months ago that showed handgun statistics and as some have mentioned, handguns in general are relatively weak manstoppers and that there is not a great deal of difference between the calibers. I also look at feedback from the street, including LEO, medical, etc. What's a round's reputation? A few years ago the top 9mm rounds were the Gold Dot 124gr. +P or non +P and the Federal 147gr. They had a good record of stopping fights and I seem to remember the Gold Dot had a decent amount of car body penetration. I don't know what the latest stuff shows, but I still like the Gold Dot. ;)

As Billy says, it's all about getting to hydraulics or electrics and disrupting them. And to a certain degree mechanical breakdown from bone breakage. I also favor over penetration vs under penetration, despite spectacular expansion. Energy transfer is a myth in handguns. See the Officer Coates story.
 
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