My friend offered to go in half with me if I bought a case of HST 147. Considering it is $800 a case, it sounded great however, I have a case of HST .357 Sig so it's hard to justify getting 9mm when .357 Sig is way better than 9mm +P, 9mm +P+ so it makes no sense to buy a case of 9mm. Anyone else feel the same?

And with the ammo shortage, I think .357 Sig will be more plentiful than 9mm

If the firearm I prefer to carry came in that caliber, I'd consider it.

Sent from my Moto G (5) Plus using Tapatalk

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Slava Ukraini!

Whatever floats your boat.

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How God has blessed us!

Interesting questions. Interesting observations.

May I suggest that you try shooting 9X19 under simulated combat conditions (low light, no hearing protection, no eye protection, maybe inside a closed room or automobile, just like it will be when you need to defend yourself in the real world), then try the same exercises using .357 Sig. Let us know how that works out for you, okay? You like recoil, you like muzzle blast, you like mega-fountains of muzzle flash, you should really enjoy the experience.

Might even save a buck or two on ammo.

I carry a full size Sig P320 .357 and can rapid fire and put all shots at 21ft about a softball size group so that is not a problem. However, the loud deafening noise it would make yes that would be pretty awful on my hearing

Because it's not......

Well, there is carry, and then there is CARRY!

If I were carrying a 357 Sig, and were constantly within reasonable distance of my ammo cache, I can see where you are coming from. However, if I was going to be away from my home/ammo cache for an extended period and I couldn't bring the cache with me, with the prospect of needing additional ammo, I would think twice about taking the 357 Sig.

Looking at this from a very current perspective, how much ammo do you take with you on an extended trip? How many of you take a box or two, thinking that should be more than adequate? Or perhaps you would buy additional ammo as you need it? With the rise of "spontaneous" violent "protests ", do you still carry your normal "load-out"?

Personally, I would try to check out ammo availability along my route! In many respects, I can see the 357 Sig round as being an "exotic" round not available in all gunshops! It would be like carrying your 16 ga riot gun or 12 ga 2 9/16" riot gun and expect to find ammo at Wal-Mart! I would carry what would be most available!

Besides, when it comes to defensive ammo, can you ever have too much?

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Judge control not gun control!

My sentiments exactly. I don't see the point in carrying a 9mm Luger when I can carry the more powerful .40 S&W or .357 SIG in the exact same size firearm.

Folks can parrot the FBI's justification for downgrading to 9mm all they want, but their Ballistics Gel Testing is not the end all, be all, and actual human beings have bones which tend to be affected far more dramatically by bigger, heavier, and/or faster projectiles, not to mention suffer less deviation when they strike a hard object such as a bone, so I choose to carry something with more oomph.

Not to say that 9mm Luger isn't a capable duty cartridge, because it obviously is adequate for the task, I simply choose to carry something more because I can and to me the sacrifice of 2-3 rounds in the magazine is more than compensated by the increase in kinetic energy.

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Shooting Comfort is bilateral.

I like the "whatever floats your boat" concept. I don't need another caliber - I'm totally happy with 9mm for SD, I can always switch to .45 ACP, and my self defense revolvers are stoked with .38 Specials, sometimes +P, never .357 Magnum except in the woods. YMMV

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Come and take it!!

357 sig won't do anything 9mm won't do.

If you think you need more gun, go to the .40,.45, or 10mm.

I have seen tests where both 9mm and .357 have same penatration but the kinetic energy from .357 cannot easily be measured.

My everyday carry is usually my FN57 because the cartridge is totally bad *** but when I am not carrying that my .357Sig is my next logical choice.

I do prefer to plink with 9mm however

In a real gunfight, you won't hear the shots. You won't see the muzzle flash. You probably won't even know how many shots you fired. Been there, done that. Just sayin'.....

Except it's not just gel tests. Results from real-world shootings show very little difference in actual effectiveness among the service calibers, from 9mm to .45ACP.

So carry what you want. They all have the potential to work if you can get rounds on target. If OP doesn't want to invest in 9mm, then don't.

Because 9mm gets all the ballistic Developmment money. 357 Sig doesn’t as sales don’t justify it. Today’s 9mm is far more impressive if you chose the right ammo. And I can still train with bucket o bullets if I chose. I still keep a 45 for nostalgia and silencer use. As always, shot placement and gun reliability are the two most important considerations.

I have done that with a SIG P229 chambered in .357 SIG (great gun). I was in a small closed room, low light, no ear protection (left ear next to a wall), no eye protection, and no problem whatsoever. I also did it with Underwood 65 gr. ammunition rated at 636 ft. lbs. which is considerably more powerful than the HST .357 SIG ammo. The recoil is very light being a 65 gr. bullet (lighter than a 115 9mm but with more muzzle blast). My left ear rang for a day or two as if I went to a Metallica concert (I won't do that again, but that would have happened with 9mm as well with my ear next to a wall) but my right ear didn't ring at all. The ringing would have been perfectly acceptable in a real world situation if it put the guy down faster and it certainly is no worse than a 10mm or .44 Magnum, that's for sure. There was no problem with flash as my vision was not affected at all. Other than price, there is NO advantage to 9mm in my opinion as a .357 SIG is a 9mm (.355") bullet. It's essentially the same projectile with the capability of more velocity when needed, and it requires one less round on average to stop someone, one-stop-shots are higher, and it is more accurate, so those are advantages in my book. I still love and prefer 9mm for smaller guns (compacts, subcompacts, "single" stacks, etc...), but in a full-size or SIG "compact"-size gun I would choose .357 SIG even over 10mm unless I was shooting a brown bear. LEO's with experience also claim it does a better job than 9mm dispatching canines and even black bear.

That is somewhat true but not completely true: An Alternate Look at Handgun Stopping Power | Buckeye Firearms Association.

Even the Secret Service was going to stick with .357 SIG until they tested the G32 and the G19. Because Glocks are significantly lighter than the P229, they felt 9mm handled better for the AVERAGE person than .357 SIG, and I concur depending on the shooter (women & smaller statured men), especially after owning a Glock 33. It is slightly better at virtually everything than 9mm by a few percentage points because of the velocity. That might not sound like a lot, and it's not, unless someone loses their life by a very close call. Certainly it is a bigger difference than those choosing between 9mm, 9mm +P and 9mm +P+. That's what makes me scratch my head. Why do all these 9mm guys (like myself) insist on 9mm high pressure cartridges but feel .357 SIG offers no advantage? I can undertand someone only shooting standard pressure, but not 9mm +P & +P+. Either way, .357 SIG has a modest advantage that may or may not make a difference. But if .357 SIG was more affordable, you could load it EXACTLY like any 9mm cartridge while maintaining the ability to increase its velocity to negotiate barriers better or to get that modest edge in ballistics generally.

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.357 SIG is more powerful on average than .40 S&W or .45 ACP. For all practical purposes it is as powerful as 10mm but with less recoil. What I mean is that you can load 10mm to have more energy, but at that point you're going to over penetrate with its heavier bullet and spend any advantage unless you're shooting bears or something. The average .40 S&W and .45 ACP is about 450 ft. lbs. of muzzle energy. The average .357 SIG is 526 ft. lbs. My 65 gr. Underwood .357 SIG XD rounds are rated at 636 ft. lbs.

I was deeply committed to 9mm and .45, years before there even was .40S&W or .357Sig.......... Guns, magazines, holsters, ammo. So I chose to pass on these young upstart calibers.

9mm,.45 , 357 ,.38sp,.380 and .22lr were enough calibers.... with track records..............................


Then 10/12 years ago I had the chance to get used but anib Sig 229 with both .40 and .357 sig barrels and 4 mags and night sights for about $500. Bought a couple (3or4) more mags and put my only.40/.357 gun in the safe. (with 50 rds of .40 and .357sig)

In 2013 after Sandyhook ....... the shelves were bare of 9mm,.45 and .40..... but .357 sig was still there....... IIRC I bought 2 50rd boxes ($60) a week for about 7-9 weeks. Picked up a few hundred rounds of .40 as it began to reappear.

Today the whole package represents my last ditch emergency stash.


Never hurts to have options and back ups to your back up plan!!!!!!!!

This comes from the same study of course and can put this in perspective a little better...



In terms of killing people, rifles and shotguns are much better, but in terms of incapacitating someone, even centerfire rifles don't have much of advantage (.357 SIG and centerfire rifles both fail to incapacitate 9% of the time).

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Why carry a 357 Sig when a (insert caliber) is so much better?


Please advise the Military, FBI and local LEO all over the world.

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Still Running Against the Wind

I'm willing to bet a dollar that 90%+ of the ".357" stats were .357 Magnum. If there was enough data on the .357 SIG, the study would have separated it out. So it's disingenuous to compare that data to the 9mm.

When it comes to .357 SIG, it seems self-explanatory that it would be more effective than 9mm Luger because it's a bullet of equal size traveling at substantially higher velocity. If folks want to argue that fact, then I would like them to explain why 9mm Luger is more effective than .380 ACP, and assuming their answer is because it's launching a heavier, higher velocity bullet, then I would like to see then explain how it is that the same factors which make 9mm Luger more effective than .380 ACP somehow make absolutely no difference for .357 SIG.

5.7x28 FN has always been an interesting cartridge to me. At one point in time it was poised to replace 9x19 in NATO Forces, but then the German delegation basically threw a fit because they just couldn't accept a German Cartridge like 9x19 being replaced by a French Cartridge, which effectively delayed its adoption indefinitely.

Recently I purchased a Romanian Tokarev TTC chambered in 7.62x25 Tokarev, which is basically the 5.7x28 FN of the early 19th century. A small caliber, high velocity bottlenecked cartridge with armor-piercing capabilities. One thing that puzzles me is why it never really made a comeback considering that it does pretty much everything newer cartridges of the same vein like 5.7x28 FN and .22 TCM can do, but with a larger bullet and greater energy.

As previously stated, the 9mm Luger is an adequate duty cartridge, meaning in terms of effectiveness, it's as good as it needs to be to stop a threat, ergo a critical hit with a 9mm cannot be improved upon by a more powerful cartridge. No sense in splitting hairs if it gets the job done.

I merely prefer .40 S&W and .357 SIG due to their potential to produce greater damage per shot in a firearm of equal size.

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Shooting Comfort is bilateral.

Couldn't you make the same argument about the 10mm over the 357 Sig? It's kind of like all the other caliber debates. 40S&W vs 357 SIG, 45acp vs 9mm, etc.

It's budget. The cost to train rises with the cost of ammo.

I guess I pretty much agree with Dr.Gary Roberts(DocGKR) when he wrote...

“Compared to a 9mm, the .357 Sig has a decreased magazine capacity, more recoil, as well as greater muzzle blast and flash, yet at best it offers no gain in bullet penetration and expansion characteristics. What is the point of this cartridge?”

I didn't even know 357sig was still a thing, I thought it was another forgotten caliber.

Who knew?

It always seemed like a good answer to a problem that didn't exist.

If you like it enjoy it!!

10mm Auto simply cannot fit inside of a 9mm size frame, whereas .357 SIG can.

For 10mm you have to go up a frame size, and for some, the grip size of 10mm is too big to fit their hands properly, which in turn results in poorer accuracy.

Also, for all the hype 10mm Auto receives, it just sort of lands in a weird spot in terms of power. Most commercially available factory loaded ammunition is loaded to FBI Specifications, making it the ballistic equivalent of .40 S&W because the 10mm FBI load was the reduced power load which was the basis of the .40 S&W cartridge. Oh, but 10mm FBI Loads cost substantially more than .40 S&W.
Boutique loads are hotter, closer to the original Norma Spec ammo, but ballistically it's generally no better than .357 Magnum at best. 10mm Auto loads which can match .41 Magnum ballistics are an Urban Legend based on some watered down .41 Magnum loads Remington offered which specifications appeared in reloading manuals.

There's a reason why 10mm Auto never really achieved mainstream popularity to match .380 ACP, 9mm Luger, .45 ACP, or even .40 S&W. Full-Power loads are better suited for quadrupedal predators like Bears than it is for humans, and the reduced power loads are no better than .40 S&W, yet they're in a longer case and cost more money. So if you subscribe to the belief that .40 S&W offers no tangible benefit over 9mm Luger, then 10mm FBI is even worse because it requires a bigger gun, costs substantially more than 9mm, and offers nothing in return for it.

It was never designed to solve a specific problem, it was designed specifically to appeal to Police Departments who favored the .357 Magnum by duplicating the performance of the 125gr .357 Magnum load which had an almost legendary reputation as a man-stopper within the field of Law Enforcement.

That being said, it definitely has its advantages, such as superior barrier penetration compared to 9mm Luger and even .40 S&W, which made it popular with Highway Patrol units in particular because it offers more straight-line penetration through autoglass, whereas the trajectory of 9mm Luger and .40 S&W tends to deviate more after striking the angled surface of a windshield.

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Shooting Comfort is bilateral.

The Sig round really doesn't have a real world advantage over the 9mm UNLESS you're talking about vehicle penetration (glass/sheet metal). Gotta agree with Dr. Roberts there.

Also real world, back before retirement, we'd invite the local VA State Police in for our night shooting work. Give them a chance to do things in dim light. After we got over the muzzle blast thing, we realized that the muzzle flash lit up our targets. We'd wait for one of them to fire and then shoot at the illuminated targets. Did wonders for our scores, the staties weren't shooting for record.

Hopefully some of you enthusiasts will realize it also locates the user for anyone with whoever you may have shot at.

I do grant that you do get the mixed blessings of a flash bang without all the restrictions of the real thing.

BTW, something to consider, I have a "moderate" hearing loss due to limited unprotected use of firearms. Along with a 24/7/365 concert from tinitus [screwed up the OSHA reports on retirement ].

That's one of the many things folks fail to appreciate when it comes to more powerful cartridges. Often times things such as a louder report and brighter muzzle flash are considered strictly detrimental, yet if you think about it, a firearm which produces a brighter muzzle flash and louder report is going to be far more disorienting, not to mention intimidating to the guy on the receiving end. A frightened, disorented, and quite possibly demoralized enemy is one who is more likely to make mistakes, surrender, or retreat.

Obviously Psychological Stops shouldn't be relied upon, but a potential advantage is a potential advantage and a victory is a victory. So if you can handle the sharper recoil impulse without any negative impact on your ability to hit the target and the cost of ammo isn't a financial burden, then I don't see any reason not to take advantage of every potential advantage that the cartridge has to offer.

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Shooting Comfort is bilateral.

But if we're basing this on frame size, you could argue that the 9mm/40/357 are all inferior to the 380acp and smaller sized cartridges.

Perhaps, but it seems to have went the way of the 40 S&W, but even worse as far as popularity and resale value.

harry knows of what he speaks. I agree. I shoot the .357 Sig well. I am not denigrating the 9mm. Carry what you like and shoot well whatever that caliber may be.

I have both 9mm and .357 Sig carry guns. Both have their place.

I appreciate the “shock and awe” of the Sig round. I’ll worry about hearing aids later.

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Rule of law, not a man.

The medical examiner and the ER doctor can't tell what caliber it was, or what the bullet design was, from looking at the body. All this obsession over bullet design, and 150 fps difference, and 1.0mm difference in diameter, is hogwash.

A bullet either damages a vital organ, or it does not. To do so, you have to put it in the right place, and it has to penetrate deeply enough to get there. If it does, it has damaged a vital organ. If not, then not.

Tell me, if a bullet makes a .356 inch hole in an aorta, what's the difference if it came from a .38 spl, .357 magnum, .38 super, 9mm Luger, or .357 Sig? None.


Same rule in the caliber wars. A .452" hole in a heart does the same thing as a .356" hole in a heart. And the heart will certainly never tell the difference between a .400" hole, and a .356" hole.

The problem with the mouseguns, i.e. .22LR, .25, .32, is not lack of expansion, it's lack of penetration. Bullets are slow and light, and just don't get to a vital organ. Except when they do, and then a .22LR's effects are just as dramatic as those produced by a .45.


Unlike virtually all internet experts, I've studied the forensics, read the autopsy reports, interviewed pathologists and ER doctors, and actually handled and photographed bullets that have killed people.

If you put the bullet onto a vital organ, and the bullet penetrates effectively, you have done all you can do. If you or the bullet fail, then not.


Anything else is marketing hype, anecdotal evidence, or replication of gun-store talk and internet lore.

For the record: I carry 9mm and use Winchester Q4318 NATO 124 grain FMJ.

I have seen tests where the .357 Sig was better than .40 caliber at penatrating pine wood

If I feel in danger of being attacked by pine wood. I'll remember this post.

Just kidding!

A 9mm in the same platform as a .357 Sig carries more bullets in the magazine because it needs to

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USS Brewton FF1086
SWCA#3597

They don't get to choose, the number crunchers do. They are stuck with what they are given, and the bottom line drives all...

Dr. Roberts does not take into account the kinetic energy of the .357 sig round. It may not penatrate any deeper but it causes more shock to the brain.

I'll stick with 5 shots of 38 special or 44 special.

Gel tests aren't the end all be all but Lucky Gunner testing basically came up with the results that there isn't much point in the hotter 357 Sig round.

Heck, I carry a 642, .38 Special.............................................

If the .38 Special won’t do the job, use the Krag.

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and what his trumpet saith

Can't remember a fatality that involved being shot with a .357 Sig down here. Mostly .22's 9's and fawtys Average shooter is poor and cannot afford the .357 Sig round. Recent homicides were going back to the basics like cane knives and folders. If it hits the right place it's gonna kill ya no matter what size round you are using . If I had to pick one center fire round for the rest on my life it would be a 9mm. Rifle round it would be the 7.62x39 Ubiquitous the world over and cheap too (compared to stuff like the 4.35 x 27 screaming whompenstomper). But for pure shootin' satisfaction, ya can't beat the good ol' .22rf. Aim straight and one will do the trick-if he's still movin' shoot again.

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Forum consigliere

There he is. Caj goes n starts a caliber war, then sits back for 40+ responses before peeking his head up.
Good job.
I’ll go back to my popcorn, carry on.

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Reg. Magnum wants/Rossi wallet

Both have been around for a long time and have proven themselves to be capable cartridges. Most civilian Self-Defense shootings are over in 1-3 shots, and you've got 2 more in reserve, so you should be fine.

Pretty much any cartridge from .22LR upward can potentially deadly if it hits the right spot, and .38 Special has served policemen well for the better part of a century right up until police started using hollowpoints, which unfortunately seem to have been rather poor performers back in those days considering that up until then the .38 Special had a good reputation.

Don't get me wrong, I'm not one of those annoying people that believes that there exists some ideal one-size-fits-all cartridge, nor that anyone who chooses to carry anything less "has a death wish" or "doesn't take their self-defense seriously" and I'm most certainly not one of those insecure men who just can't live with the fact that other men may opt to carry something more powerful that I. In fact, I find such naive people to be utterly insufferable. They're always going around, second-guessing everyone and making ignorant statements based purely on conjecture. The Village Idiots of the firearms community.

For the longest time I carried nothing but a .380 ACP pistol, and to this very day I feel that .380 ACP is a viable choice for self-defense, I only started carrying more after wild animals started wandering out of the woods which surround my neighborhood. (.380 ACP may be adequate for bipedal predators, but hardier quadrupeds...?) Besides, I can handle more, so why not? So now I carry a .40cal because that's as low as I'm willing to go when it comes to dangerous animals like boar. Some would say it's insufficient, but it seems to be enough for a number of park rangers as well as Fish & Game.

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Shooting Comfort is bilateral.

That's a fair question, but what are you basing that on? Isn't it just as questionable to ignore the claims by dismissing it without knowing? You might want to contact Columbus PD LEO/LEO firearms instructor Greg Ellifritz who spent ten years collecting the data for this study and see what he has to say about it.

The data was collected in this century so I would imagine that the vast majority of guns were either snubbies which lose their ballistic advantage because their short barrels have no advantage over 9mm (see MAC's video comparing them) or .357 SIG semi auto pistols (particularly popular in certain law enforcement agencies like state police). I'm sure some of these were long barrel revolvers, but to say 90% of them were in the 21st century is a logical leap in my opinion. It is a valid logical leap, in other words, I think it's a good question, but I think it's a poor basis of dismissing an LEO's hard work without inquiring about it.

Remember, the .357 SIG is NOT a .357" bullet like the .357 Magnum, it's a .355" (9mm) bullet designed to mimic the 125 grain .357 MAGNUM LAW ENFORCEMENT LOADS that were most popular after decades of use. While .357 SIG loads are on average less powerful than .357 Magnum loads (526 vs 574 ft. lbs.), .357 SIG is more than capable of delivering this energy without over penetrating (e.g. my 636 ft. lbs. of my 65 grain Underwood XD bullets which deliver a larger permanent wound channel than any .357 Magnum hollow point).

If Ellifritz didn't feel he had enough .357 SIG data, he likely would have pointed this out as he did in the study regarding other calibers. It's still a valid question, however, but as I pointed out, that may have been a valid conclusion 30 years ago, but in this century it is far less certain. Finally, even if that is the case, the .357 SIG was designed to mimic the best LEO .357 Magnum loads which are not the most powerful ones as over penetrating will result in sacrificing any ballistic advantage a more powerful load has. For example, if you note in the study, .44 Magnum fails to incapacitate 13% of the time tied with 9mm and .40 S&W despite having double the energy. That's because so much of it leaves the body as the bullet passes through. As one medical examiner pointed out in an article, he never personally saw a .357 caliber bullet leave the body and he never saw a .44 Magnum stay in one.

So what you're saying about 90% of the results likely being .357 Magnum is certainly worth investigating, but it is far from likely in my opinion. And even if it was true, that might mean .357 SIG is even underestimated as a .357 SIG bullet is going to deliver much more energy than a .357 Magnum snub nosed revolver.

What is great about .357 SIG is exactly what is great about 9mm. In my opinion the .355" diameter is more efficient and generating power (remember, k.e. = 1/2 x mass x velocity squared which is why a premium is placed on velocity). This is because 9mm bullets are lighter and have a greater BC (ballistic coefficient) which means that they are more aerodynamic than larger diameter bullets but they don't drop off in performance as we see with smaller rounds like .32 ACP and .25 ACP which fail to incapacitate approximately 35-40% of the time compared to 9-13% of the time like 9mm, .357 SIG, .357 Mag, .40 S&W and .44 Magnums as indicated in the study. Are you starting to see a pattern emerge?

I don't want to answer for him, but the answer is at least not necessarily (if not no). His point is that .380 ACP, 9mm Parabellum, and .357 SIG are all .355" (9mm) bullets differing only in velocity (with gains being had each time velocity significantly increases). .380 ACP and .357 SIG are marketing devices meant to remind people that they were semi-auto cartridges meant to provide the ballistics of a .38 Special cartridges and .357 Magnums respectively. A 10mm is a .40" bullet just like a .40 S&W. The larger diameter bullets have a lower BC (ballistic coefficient) which means they are less aerodynamic (the higher the number the more efficient it is). This is important because velocity builds energy exponentially more than mass (which is why a 6.5 Creedmoor out performs .308 after 300-500 yards). More importantly, this is also why the basic formula for kinetic energy is k.e. = 1/2 x mass x velocity squared. This means that you take 1/2 of the mass and multiply it times the velocity squared (times itself) because the latter is that much more important in building energy (which is part of why smaller/lighter/faster pistol rounds penetrate body armor whereas larger/heavier/slower rounds do not). The .355" bullet is simply more efficient than a .40 S&W or even a 10mm in building energy because it can go much faster (which would require more powder to propel a heavier round to an equal speed).

Now 10mm has a large enough case to increase the velocity significantly enough to provide more energy than a .357 SIG, but a 630 ft. lb. 10mm (.40") bullet is going to be heavier than a 630 ft. lb. .357 (.355") SIG. This is going to do two things. One, heavier bullets tend to penetrate deeper (all things being equal). If you look at bullets in general, the hotter 10mm self-defense rounds have a harder time staying within the FBI's guideline of 18" of penetration. When they do they can technically offer more energy, but remember, most penetration ratings are averages, so the higher the average, the higher percent of projectiles are still going to leave the body. So for example, an underwood .357 SIG might be rated at 17.5" and a 10mm at 18". As an average, the latter will over penetrate more. Does that matter? I don't have the data to say one way or another for sure, but the heavier projectile relying more on mass than a smaller bullet (which relies more on energy) is going to provide more recoil which means follow up shots are not as fast with 10mm. This is why in my opinion 10mm is not as good unless we're fighting brown bear. Like I said, however, that is only speculation on my part because 10mm was not prevalent enough to include in the study I cited herein. But for all these reasons, it's a good bet .357 SIG is better. There's a reason why the secret service chose it over 10mm. And they would have stayed with .357 SIG but the service is more inclusive than it used to be (to include women and smaller statured men). As I pointed out, they were interested first in adopting the Glock in .357 SIG but their smaller shooters have a harder time with the muzzle blast even though a 125 grain 9mm Parabellum bullet and a 125 grain .357 SIG bullet have the same amount of recoil (Newton's Third law). The muzzle blast is more substantial, so it makes the same 9mm bullet more flippy in a .357 SIG. That said, a 65 gr. .357 SIG is less than half the weight and delivers far more energy and it is a *****cat compared to 10mm.

Exactly. It's also because of "diversity" (the inclusion of women and smaller stature men). Interestingly enough I went to Fort William Henry/Fort George on Lake George years ago, and the tour guide, who was also a PhD student, mentioned something interesting. According to the fort's records, even though men were shorter back then, the soldiers had to be 6 ft. tall minimum. This was true more or less on average in law enforcement and military applications until the 1980's and is even more so today. THAT is at least part of the reason we don't see .357 SIG more popular as you and I know it can do everything a 9mm can do but better.

No one said they had to. They have other information to go on like the firearm recovered.