So I'm perusing the ballistics data for factory 10mm "performance" loads over on Lucky Gunner - tested from a Glock 4.6" barrel and was struck by how low is the velocity of most loads. So I do the math. Turns out, several of the "performance" loads barely crack 400 foot-pounds of energy! Few rise above 500 fpe., and only one broke 550 fpe! Mind you this is for expensive ammo.
So then I compared the so-called performance 10mm to .40S&W actual shooting data. I must also point out the .40 was shot from a Glock 27 with 3.4" barrel, not a comparable barrel. Most of the 165 grain loads exceeded 400 fpe, and most of the 180 gr. loads were just barely under 400 fpe - from a barrel 1.3" shorter than the 10mm loads!

Being a lifelong reloader and "new ammo loader" I know how easy it is to load both .40S&W and 10mm to better numbers without even pushing the envelope - yet the companies who promote their super-special loads at premium prices can't seem to manage better? Why should they, how many people being ripped off for ammo labeled 10mm have any way to check, and those who do and report on forums such as this one are only "preaching to the choir" as they used to say.

Finally, I do some comparison checking of 10mm fraud loads against the old standby .45 ACP. Lucky Gunner tested .45 performance loads from a 3.6" barrel Kahr CW45 - 1.4" shorter than the 1911, and clearly biased toward more concealable pistols. As expected, .45 185 gr. loads are just a step behind the 10mm Fraud loads, and that's from a shorter barrel and not even +P! Again, from a handloader's perspective, the .45 auto can be easily loaded to 500 fpe with little added pressure - that's not even a full .45 Super power load. Matter of fact, Underwood lists a 185 gr. JHP+P that comes very close to 600 fpe! (And don't even get me started on the .460 Rowland!)

Of course if we start comparing Underwood to Underwood, the 10mm makes a proper showing, but that's not the brands whose names so often pop up on forums such as this one being considered by consumers who should be getting the performance they're paying for.

Let me reiterate the ballistics testing used a full-size barrel for the 10mm, and compact - even sub-compact barrel lengths for the .40S&W and .45ACP.

I've often wondered why commercial 10mm is so underpowered from what it should be. If I wanted that performance, I'd be shooting a .40 S&W, which is barely above 9mm, to be honest. Serouusly, most 9 and most 40 are in the same power range.

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NRA RSO

...was supposed to be comparable to something like a .357. But from the data you present it seems that the only thing you get with commercial ammo between 9, .40 and 10mm are bigger bullets.

Just a thought. Maybe ammo makers are now turning out ammo that is designed not to hurt people to prevent lawsuits.

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"He was kinda funny lookin'"

I’ve got one thing to say. If you want .41 Magnum power, don’t let yourself be fooled into thinking you really will be getting it with a 10mm pistol. More rounds, yes. The same power, no.

The original purpose of the 10mm pistol (200-grs. at 1200 FPS) was to provide .45 power at extended ranges. The old shooters used to say you could gauge it by how effectively it knocked down pepperpoppers (or something like that) beyond 50-75 yards, where, in their view, the .45 started to run out of steam. No one seems to remember that nowadays.

My understanding is the 10mm was NEVER intended to compare/compete with the 41 magnum, but rather the 357 mag.

Similar power but from a conventional format semi-auto. Faster to reload, slimmer profile to concealed carry.

What is beyond debate is that mass produced and marketed 10, and 40, are very watered down from what they should be.

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NRA RSO

The original Norma 10mm commercial load was pretty hot stuff. The current loads are very modest by comparison.

10mm Auto, in full power form, falls well short of 41 Magnum ballistics, but easily matches and can slightly exceed those of the 357 Magnum. But, that is in full power form, not the reduced loads that most ammo manufacturers offer these days. If you want true 10mm Auto ballistics, you pretty much have to buy boutique ammo or reload your own.

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VCDL, GOA, NRA

Agree. Current 10mm commercial offerings are but a shadow of what they could be or even what they originally were.
You need to load your own.

The 10mm fraud began with the original loads from Norma. While they advertised a 200 grain bullet at 1200 fps out of real guns that ammo typically produced about 1000 fps. See YouTube links at the end of this post. Factory 10mm ammo was never as hot as fans of the cartridge want to believe it was. Ammo makers have been making optimistic performance claims as long as there have been ammo makers. And 40 years ago there were a lot fewer people with chronographs to check up on them.

The SAAMI specs for 10mm call for a cartridge that has 7% more pressure than 40 in a case .1 inch longer. That does not add up to the kind of power increase most people want and expect out of a 10mm handgun. I suspect what happened is the 200 grain bullet at 1200 fps number was based on much hotter ammo produced before there was a SAAMI spec. I saw that happen on a few wildcat rifle cartridges that were given SAAMI specs in the 80s too. The SAAMI spec ammo was typically quite a bit less powerful than ammo produced by magazine writers with no way to measure pressure.

While the current SAAMI spec is disappointing it actually made sense at the time. The 10mm was meant to be a police service and self defense round, not the hunting and grizzly bear stopper it is viewed as today. A lot of the first 10mm guns were hastily converted 45s like the Springfield Omega I had that broke twice when shooting what people today would consider "real" 10mm ammo.

There really needs to be a spec for 10mm +P or even 10mm Super. There are people that tell me boutique ammo companies and reloaders can produce ammo that actually produces the kind of numbers Norma printed on their boxes without exceeding the SAAMI specs with a magic type of powder but there is no such thing as magic. They get those numbers by exceeding the SAAMI pressure limits. The ammo may be safe and reliable in their gun but will often malfunction in guns designed for SAAMI ammo. Look at the numerous complaints about the new 10mm M&P and other guns not being able to handle Underwood or BuffaloBore ammo. Guns designed for SAAMI spec ammo may or may not work with ammo loaded hotter. Gun makers need to design their guns around a spec. They are going to use SAAMI as the source for that spec. They need a number, not a vague description of what "real" 10mm performance is.

I have two 10mm pistols, a Gen 3 GLOCK 20 and GLOCK 29. Both are older large frame models before the whole "SF" craze hit the GLOCK market. I picked them up for cheap when 10mm was not popular. Full power Underwood is good stuff, but yes, commercial loads are anemic to say the least. In the end, 10mm marketing is folks selling the sizzle and not the steak.

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GOA FL Dir. & Nat. Spokesman

There are still a lot of 10mm pistols out there lacking full chamber support, including many 1911-types, and early Glocks. While SAAMI standard is 37.5k lbs., a number of commercial loaders have chosen to limit their offerings to 30k in deference to those pistols lacking full support. Some cases in some pistols can experience a rupture ahead of the case web, resulting in high-pressure gas escaping into the mag well, usually damaging the magazine and the grips, at least. The industry as a whole, recognizing this, has made advances in design and construction to address the issue. Kimber 1911s and newer Glocks, for example, feature barrels which better support the case head down to the web. Noted gunwriter Brian Pearce has followed this and spoken of it, e.g. Handloader 314.

Can only relate personal (limited) experience. I and a shooting compadre 'bit the bullet' and ordered Bren Tens. After months of waiting we finally received notice that our pistols were ready to ship, but . . . "the magazines would be shipped at a later date."
Uhhhhh . . . nope, nope and NOPE - we canceled the order. (by that time the news was out about the magazine problems and availability)

So what to do with the split case of Norma 10mm we had already ordered and received ? We promptly ordered two (by then) available Colt Delta Elites. Other than trial sighting/function shots the only real test we ever put it to was for some bowling pin matches. (For those unfamiliar an array of pins was set on the front of a three foot wide table - to score, the pin had to come off the table completely and the fastest time to clean the table won).

I watched as guys tried everything from 38's and 9mm's to 41 and 44 mags. The smaller rounds would knock the pins over and several follow up shots and/or reloads were required to finally push the pins (now rolling around on the table) completely off. Conversely, many times the magnums would blow big chunks out of the pins as they passed through and more often than not required additional hits to take them completely off the table after knocking the split and splintered pins over..

As I said, relating personal experience here, the Norma 10's through the Colts knocked the pins straight back off the table from three to five feet when hit in the 'sweet spot' (a point just under the logo under the neck of the pin) and later examination showed most of the time the expanded hollow points were still in the pins stopping just short of punching totally through the plastic shell at the rear of the pin.

An isolated limited test to be sure but that's what I experienced (this was also pre-40S&W). Never did chronograph the Norma factory loads but they were indeed hot. And for that application I never saw anything work better while I was shooting those matches.

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Qui plantavit curabit

I have a 10MM,, (Colt, Gold Cup) ,, and I have a concept about the ammo.

The ammo is sort of like any other thing that you buy,,

Pasta at Olive Garden type restaurants is prepared with "LOTS OF SUGAR"
WHY,,?? because it brings customers back.

The same with 10MM ammo,,
If you buy Brand X 10MM ammo, and it punishes you to shoot it,,
then, you buy Brand Z 10MM ammo, and it is pleasant to shoot,,,

Guess which ammo you will pick up next time??

NOT Brand X,, you don't want to spend money to be punished.

After the first outing with my 10MM,,
I have never shot anything in my 10MM other than reloads,,
they are mild reloads, and are pleasant to shoot,,,

This 10mm resurgence started when people turned away from .40 to 9mm. What did you think the manufacturers were going to do with all the .40 bullets that no one was buying?!

They thought…we will just make 10mm and we can get rid of them that way.


Sent from my iPhone using Tapatalk

I guess I have to go back to the good ole stand by, Location, Location, Location. If you are looking for a defense load then I think anything over 700fps will work depending on distance. If you are looking for something in the hunting range then you will be paying more for you ammo. But seriously folks, has anyone ever complained about what they were shot with?

Every new cartridge that comes out is selling something better. Just look at the rifle market. Even the pistol market is always coming out the the new/better. Look at the 5.7 and the 30 Super Carry to name only a couple. Who is to blame, the gun makers and ammo manufacturers or the people that are gullible enough to always buy what they are selling?

The 10mm overlaps the 357 magnum ballistics. They both range from around 400 foot-pounds of energy and top out around 800 foot-pounds. Most ammo manufacturers list their ballistics from a six-inch test barrel. The 10mm has a slight advantage over the 357 magnum with heavier bullets and more momentum.

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U.S. Navy - U.S. Army, ret

Hey wait a minute, the .357 SiG was supposed to be the .357 Mag auto. (In reality it was comparable to the Super .38 Colt.)

I had my chronograph at a buddies a couple weeks ago checking some handloads for 10mm, 357 mag, and 45 ACP.

He brought out a box of 10mm factory ammo, I forget the brand? Pretty light bullet, 125 grain maybe? Anyways the box said IIRC, like 1,550 FPS? Somewhere in there?

They were like barely over 1,200 FPS. My 155 grain XTP's with power pistol were 150 FPS faster.

He was shooting them in a S&W with 4.5 in barrel I believe?

The claimed velocity wasn't even close to the real velocity. In this gun anyways.

I never bought the 10mm or 40 S&W Kool-Aid.

I always was a big fan of the 45 ACP autoloader and the 357 Magnum revolver.

Then why spend the extra money on 10mm stuff when .45 acp is not only cheaper, but more available in a much wider variety of guns?

Sounds kind of like the 10mm has ended up exactly where Col. Cooper wanted it to be in the first place. A 200gr bullet at 1,000 fps.

Here’s your answer folks. The same reason people buy 44 mag revolvers and then say ” I only shoot specials so the gun doesn’t get beat up.” When reality is “ I only shoot specials so I don’t get beat up.” More weight shoved out of a barrel means more recoil. Or more velocity from the same weight.

And frankly, urban self defense doesn’t require anti grizzly levels of power.

10mm is a great cartridge, but takes a ton of practice to handle it. Practice isn’t exactly economical these days compared to 9mm. Well, 10mm never was economical, but you get my drift.

I love my Smith & Wesson Ten Ought Six. I have a few boxes of the original Norma 200 grain truncated FMJ loads. It didn't seem all that hot to me. I don't have a chronograph but my notes say that when it was tested the actual velocity was about 1125 fps rather than the 1200 fps printed on the boxes. I have some of the Underwood 180 gr. JHP ammo, their published data says 1300 fps and I have read reports that it chrono's around 1250 fps.

The weakest factory ammo is supposed to be the Sellior & Bellot and Federal 180 grain FMJ's, they are supposed to clock between 1165-1200 fps and testing shows the actual velocity is more like 1050 fps.

Since even the lighter weight bullets aren't that fast, I won't shoot anything lighter than the 175 gr. Silvertips in my 10mm. Might as well go with the extra mass.

WHY!!?? Because I walked in a LGS one day,, that is why.

It happened to be during the time that everyone HATED 10MM,,
and they wanted rid of them at ANY cost..

A guy had a Gold Cup 10MM on consignment,, and after a month, there were no nibbles.

When the guns owner walked out, I followed him, and asked him what he wanted for the gun,,

He said $350,, I told him to go in and get off consignment,, I would buy it.

When he came out, I had the $350 ready,, he handed me a big box!!

I got the gun, and factory box,
and
reloading dies
200 - 300 bullets
a couple hundred 10MM brass
a couple boxes of primers,,
and maybe some other stuff.

I was expecting to get the gun!!

That is why I own a 10MM Gold Cup,,

The issue is when Norma began production of 10mm ammo they did NOT follow SAAMI specs, they followed European specs, CIP. In general CIP specs are about 5% higher then SAAMI spec. Plus this was back in the day when everything was overblow, possibly a result of the huge amount of cocaine being consumed at the time (did I just say that? Miami Vice)

Anyway the original ammo was found to be far more powerful then the guns could handle a study diet of, largely because Norma HAD delivered on 200 at 1200, and the Bren 10 designs had assumed they would deliver 200 at 1075-1100. Add in the unsupported chamber of Colt's Delta Elite and pretty quick the major US ammo manufactures downloaded the 10

Having 2. My Dillon can crank out any load I want......Mostly 7/8 throttle to full. Never shot factory ammo. Same with my forty's. I like both(and dozens of other calibers) so I DON"T do comparisons......I just enjoy.

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S&W Accumulator

If I wanted 9mm performance, I would have purchased 9mm. My pocket pistol is a Taurus G2C in 40. They stopped making them. With it's short barrel, I need a 40 to get the power of a 9 in a longer barrel. And it takes Sig P226/229 magazines.

I have 2 different 10s, and will be buying a 3rd, a Glock 29.

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NRA RSO

I try not to get involved in all the caliber wars and the rest. I try to keep it simple.

For SD I carry the .38 Special + P with a 135gr bullet, 9mm standard velocity with a 124gr bullet and the 45 ACP standard velocity with a 230gr bullet. That's just what I like and feel it's all I need to stop an attack.

Woods carry and the like is a totally different story.

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Freedom is never free!!
SWCA #3437

There is a significant difference in the method of chamber pressure measurement between CIP and SAAMI. CIP measures pressure at or very near the cartridge case mouth, SAAMI measures pressure at the midpoint of the cartridge case. With many calibers, the same ammo will produce a CIP pressure that is higher than the SAAMI pressure.
With the Bren X, there were reports of cracked slides, but that may have been a result of D&D's questionable quality control. Slides and receivers were not always properly heat treated and there were likely porosity issues with some of the castings, but with lots of orders, slow production, and mounting bills, faulty parts were assembled into functioning pistols and shipped.

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VCDL, GOA, NRA

I read all the posts in the thread. I think "fraud" to describe current 10 mm Auto loads is a bit harsh, but as with many other hotter calibers it would be nice if the manufacturers would state real-world velocities. If this were to occur people could make up their minds as to whether a 180 gr at 900 fps (.40 S & W) is worth the difference from 1050 fps. But if you have a 10 mm pistol, a .40 S & W is not going to fit and function. Maybe have one of each.

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Alan
SWCA LM 2023, SWHF 220

Quite a few 10mm pistols are reported to fire 40 S&W ammo just fine...

Regards!

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Sit Reloader Sentiret

At first they were building 10mm on 9mm frames and all that noise. It took a few years, and police departments handing in their guns to trade back for 9s.

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"He was kinda funny lookin'"

Having actually put lead on meat I can say that even moderate 10mm loads are very effective at killing deer. The 10mm is one of those ballistic anomalies where the paper stats and real world measurements don’t jive. I find it better for the task than 45 ACP and 45 Super as it shoots flatter and it’s been easier to achieve the type of accuracy that I require in a hunting pistol. Where 10mm really shines is in a 6 inch barreled long slide. My preferred loads would only be considered “warm” but yield Skoal can accuracy at 75 yards. At 50 yards I get pass through on Midwest whitetails.
You have to get past the paper stats to understand what a cartridge can really be.

Now one thing that is absolutely BS about the 10mm is its mythical ability to stop bears in their tracks. It works well for deer and hogs but the actual terminal performance is no where near what is required for such a large animal. You gain capacity over typical revolver offerings but you cannot come close to what a 44 or 45 Colt can do.

The 10mm has killed at least one polar bear that I know of.

If you roll your own 10mm can be anything you want it to be (within reason of course).

Actualy NO, you can NOT build a 10mm on a 9mm frame. The cartridge is too long to fit into the magazine/frame.

What was happening was the early 40 cal guns were built on 9mm frames, guns like the Glock 22, Smith 4006 and Beretta 96. Pretty quick the manufactures figued out you can not just fit a new barrel and slide and call it good.

Beretta had to redesign their slide to make it thicker where the locking block locked in. Browning went to a third locking lug on the Hi Power etc.

They were wearing out a lot of guns way too soon.

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"He was kinda funny lookin'"

It seems more to be under 'cartridge development'. Or maybe 'undevelopment'.

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"He was kinda funny lookin'"

A lot of the early 10mm guns like the Springfield Omega I had were 45s with a 10mm barrel and stronger recoil spring. Like the early 40s based on 9mm designs many of these guns failed to handle the higher pressure and greater energy of 10mm. The locking mechanism on my Omega broke twice before I sold it.

Think some of the less-than-stellar rep that the 10mm gets is from the proliferation of the 10 LITE ammo that has been around so long.
My PD's first auto was the S&W M1076 in 1989/90. Issue ammo was the Federal, or sometimes Remington 180 gr JHP at ~950 fps.
This was before the .40 S&W was even born, but 10 LITE essentially produced ballistics that the .40 would have when it came out a few short years later.

The 10mm is one of several calibers I have that I'd not even bother owning if I didn't handload. Using good published loading data the 10mm can be loaded to it's original higher performance levels before the 'LITE' concept was adopted.

I still enjoy shooting my 1076 on occasion, but really prefer my Colt Delta Elite SS.

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Ret'd LEO
SWCA #2275

I blame Hollywood and the FBI for all the 10mm. trouble. First that guy Sonny on Miami Vice was the only person known to have more than one magazine for the Bren. Then some FBI guy thought a 10mm would be cool.

Well it turns out the SA's aren't really into guns or recoil. Qualifications plummet.

So the wonks start downloading and come up with a .40 cal. Then go out on bid for someone to manufacture a suitable. 40 cal. The FBI goes all in and starts a rush to go bigger and better. All along nobody noticed their HRT and SWAT boys are still packing .45 ACP's. It's all about spending tax dollars.

The 10 mm has nearly died out several times. The Bren 10 had trouble from the beginning, but the royalty of law-enforcement, the FBI adopted the cartridge and it became slightly more popular for a while. Then they dropped it, and it nearly died again. Later people started buying it again and then, for some reason in the last few years, lots of manufacturers have been turning out guns for it. Many have tried to handload it more powerful and call it the equal to a .41 Magnum but the shooting community will call BS really quickly on something that’s not truth. Most people are now realizing that it is what it is, a little more powerful and flat shooting than the 45 ACP and it’s chambered in light weight guns that hold lots of ammo. In that role, it really has no competition in semi auto mass produced pistols. You can get a more powerful semi automatic handgun in the Desert Eagle but it’s definitely no high capacity lightweight but with the 10 mm’s new popularity I think we’ll see some improvement in the ammo in the next few years, and the guns.

And that single incident is the primary launch for the 10mm hysteria. Sales of Glock 20s would have been in the low hundreds had that poor bear gone a different way that day.

I used to think the .40 was developed as a downloaded 10mm too because that's the common belief. That was until I spoke to someone who was around during the development of the .40 and it was not because of the 10mm, it was developed independently. It had nothing to do with the recoil of the 10mm. The only thing they have in common is the bullet diameter.

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Freedom is never free!!
SWCA #3437

Although I do not own one I am sure that the 10mm auto in a large full sized gun (1911 with fully supported chamber or a 4506) can be loaded to 1200 fps with 200 grain bullets. I shoot .45 Super loads in my 4506 with a chronographed 1230 fps with 200 grain cast and 1040 fps with 255 grain cast. No case problems, no function problems...

Lately, I've been seeing quite a few ammo tests of 10mm and 40 S&W where the velocities aren't getting close to what it says on the box. Nearly all the testers used Glocks. I'm wondering if not only is the ammo not as advertised, but maybe Glock are turning out guns with slow barrels.

I know chronos vary, but when I see a guy test a 40 S&W load and it's way slow and doesn't expand, then two minutes later he has a 9mm round that does what it says on the box, I'm prepared to believe that his instrument is working AOK.

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Release the Kraken

I have been shooting and loading for the 10mm since it’s inception. I too was one of the unfortunates that’s ordered a Bren Ten, then ended up shooting the Colt Delta Elite.
When Glock introduced the model 20, I grabbed one and have shot & carried it ever since.
I have a bunch of 10mm pistols and three 10mm revolvers. My EDC is a G20 loaded with Federal 200 gr HST’s that clock at 1104 out of my pistol.
Can I load 200 gr bullets up to the “Norma standard” of 1200 plus fps? Yes I can, and have. But what do I gain with the additional 100 fps? Nothing earth shaking.
I have shot several big bodied deer and a bunch of Texas hogs with 200 gr 10mm loads, and those loads when placed properly most definitely delivered the goods.
I was on deck during the 80’s & 90’s when the FBI was looking at the 10mm and I know what went on there ( there is a lot of disinformAtion about that subject) and I know how & why the 40 S&W came to be.
I recently tested some of the latest and greatest factory 200 gr loads and the one’s I tested ran close to 1100 fps in my G20 & Smith 610.
As pointed out in previous posts, a lot of these manufacturers are way too optimistic about their MV numbers.
I also tested a Brand that had a 200 gr hard cast bullet that was rated at 1300 fps out of a G20. It did not make 1300, or 1200, it ran at 1150 fps out of my G20.
As noted, I have been a 10mm user since it all began. There are more handguns and ammo for the 10mm than ever before.
I shoot primarily 200 gr bullets in my 10’s. I know what the factory loads produce and if I feel that I need more horse power I head for the loading bench. But truthfully, a 200 gr bullet at or near 1100fps has pretty well covered all the bases for me.

Few companies actually load 10mm Auto up to the fabled "200grs @ 1200fps" specifications of the old Norma loads and why should they?
After all, such loads have yet to be proven to actually even existed since all tests of vintage boxes of Norma ammo have fallen short of what was printed on the box. Besides, most shooters don't actually enjoy shooting such hard-kicking rounds, so why should the average ammo manufacturer load their 10mm Auto ammo that hot when the average shooter cares more about bragging that they own/shoot 10mm Auto than actually shooting full-power ammo?
Furthermore, let's face it, most commercially available 10mm Auto Pistols are just modified .45 ACP Pistols which really aren't designed to handle such high pressures. There's a reason why those who handload 10mm Auto to 200grs @ 1200fps often recommended modifications to existing 10mm Auto Pistols such as aftermarket barrels with full chamber support, heavier recoil springs, recoil buffers, or even compensators.

So yeah, if you really want full-power 10mm Auto loads, then you have to either handload or buy boutique ammo by manufacturers such as Buffalobore, Underwood, or Cor-Bon. Also, you'd probably better get some heavier recoil springs for your pistol too, because they're probably tuned for your typical 10mm Lite loads, not full-power stuff.

Unfortunately, most 10mm Auto ammo is just .40 S&W ammo in a longer case that manages to get slightly higher fps from chronograph tests by virtue of the fact that most 10mm Pistols have 5-6" Barrels while .40 S&W Pistols barrels are more commonly 4-4½".

Truthfully, pretty much all factory ammo save for 9mm Parabellum and .45 ACP are downloaded these days. Yes, even .40 S&W got watered down a bit over time thanks to all the cheap .40 S&W Pistols which were merely modified 9mms, sound familiar?
Fortunately, factory loaded ammo of all major Duty Cartridges are sufficiently powerful to handle the majority threats one might encounter in North America, so unless you're living in Alaska or something, you're probably fine carrying whatever you please. Sure, some cartridges are more powerful than others, but a critical hit from any of them will have the same result, hence why so many folks have hopped onboard the 9mm Bandwagon. It works! It doesn't mean you have to carry it — I'm still a .40 S&W guy, myself — it just means that the race for small arms supremacy was rightfully settled once Jacketed Hallowpoint technology had been perfected and ammo manufacturers started designing all of their ammunition to achieve FBI Specifications, leaving everything more or less equal. So the only thing you're actually choosing when you select a duty cartridge these days is how big of a hole you wish to poke in a badguy and how deep you want that hole to go.

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Shooting Comfort is bilateral.

As with the original intent of the FBI when the 10mm was first issued there was a huge cry from all the folks used to 9mm and .38 special so....the 10mm was downloaded seriously from its potential that could and does compete with the .357. Eventually the .40 was the settling point, I shoot tons of .40 and like it in a couple of different frames from .40 shorty Glock compensated to HK USP Tactical suppressed which remains the most accurate semi auto firearm I have ever owned or shot with a slight nod to my Model 52 as the most accurate handgun. My wife is scary with that thing, I would not want her taking her time shooting at me while popping her chewing gum. I know an ex-FBI gal whose husband loads .500 S&W loads for her and brother she is accurate with that thing pushing big lead projectiles at low velocities. I'm an advocate of large caliber projectiles at relatively low speed with a shooter comfortable and confident in their ability. Pretty tough to argue with a gaping chest wound...I'm right on the verge of messing around with a 10mm, one is available to me. It would be tough to budge me off my favorite .44 special carry piece.