Why .40 when there is 10mm?

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10mm was more of a phase for me, I bought a G20 and added a 6 inch barrel and Dawson precision sights with the intent of using it for deer. When you load up 180's to 1350 fps, the 10mm has way more recoil than 9mm, .40 or .45, there is just no way around that. I decided that real 10mm loads had more recoil than was ideal for a defensive cartridge, and that I could shoot my S&W 629 .44 more accurately than the 10mm for hunting uses. So the 10mm got passed on, and now I have .40, 9mm and .44... I'm pretty sure I'm not missing out on anything by getting rid of the 10mm, but if other folks think they have a legitimate use for it, or just want to use it, that's their business.
 
It seems the norm for some to say the 10mm is a good choice for the woods and either say or imply that the .40 or .45 isn't. The issue that I have is that if I load up a G20 (I've owned several) shooting a warm 180gr at 1350 fps, what exactly will that absolutely kill that a warm .40 180gr @ 1300 fps from a G35 or warm 230gr @ 1000 fps from a G21 will not?


I'd like to know what the 10mm diehards opinions on this are.

I think your numbers are off on both the 10mm and the 40SW.

As for the difference between 45 and 10mm, it's velocity, frontal area, and sectional density. The 10mm has less frontal area and can throw bullets with higher sectional density at significantly greater speeds. So... I am guessing with hard cast bullets with a good meplat, this translates to the 10mm doing slightly less damage to the insides of a bear at 3 feet deep as compared to what the 45ACP is doing at 1-2 foot deep. Or something like that. IOW, the 10mm can do a lot more damage than the 45ACP at the depths that could matter for a frontal shot on large game.

You can't do that with a souped up 45ACP short of using a saboted bullet.
 
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To end the 10mm vs 45 acp vs 40S&W vs 9mm debate just go to Clark Customs and get the 460 Rowand conversion for the single stack 45 with the 5 inch barrel. Drop these parts into a high quality 45 acp and with the 460 Rowland brass from starline you will change the 45 into a 44 Magnum like performer. That conversion kit is debating on jumping into my 45 acp, with double the energy of a standard 45 it will blow the 9mm 40 S&W and the 10 mm out the water. The 460 brass will not chamber into the 45acp chamber and that is basically all the difference there is and that is so the 460 is not run through a standard 45acp.
 
sfed said:
To end the 10mm vs 45 acp vs 40S&W vs 9mm debate just go to Clark Customs and get the 460 Rowand conversion for the single stack 45 with the 5 inch barrel. Drop these parts into a high quality 45 acp and with the 460 Rowland brass from starline you will change the 45 into a 44 Magnum like performer. That conversion kit is debating on jumping into my 45 acp, with double the energy of a standard 45 it will blow the 9mm 40 S&W and the 10 mm out the water. The 460 brass will not chamber into the 45acp chamber and that is basically all the difference there is and that is so the 460 is not run through a standard 45acp

It can work but there's also the fact that you have to use a comp for the 460 Rowland, which isn't bad but it increases weapon size. There's also a number of reports that functionality isn't that great. It can work yes but sometimes things just don't gel like they should in all platforms.

I've played around with this, or a very similar concept. Starline .45 Super brass is as strong as their 460 Rowland brass (according to them) and as long as the same OAL is used, you can load the .45 Super exactly like a 460 Rowland, all you need is a well supported .45 ACP barrel that is threaded for a comp. I use a custom 8 port comp on a threaded KKM barrel to help slow the slide speed down as well as cut recoil which is a must when driving 255gr WFN hardcasts to 1325 fps or 300gr LFNGC to 1150 fps from a 5" Glock.
 
GLOOP said:
I think your numbers are off on both the 10mm and the 40SW.

As for the difference between 45 and 10mm, it's velocity, frontal area, and sectional density. The 10mm has less frontal area and can throw bullets with higher sectional density at significantly greater speeds. So... I am guessing with hard cast bullets with a good meplat, this translates to the 10mm doing slightly less damage to the insides of a bear at 3 feet deep as compared to what the 45ACP is doing at 1-2 foot deep. Or something like that. IOW, the 10mm can do a lot more damage than the 45ACP at the depths that could matter for a frontal shot on large game.

You can't do that with a souped up 45ACP short of using a saboted bullet]

My numbers aren't off really, having handloaded for both (well all three in this example) for a long time I know that 180gr doing 1350 is possible from a G20 and that 1300 is possible from a G35, both a touch on the warm side no doubt. I can certainly agree that the 10mm (and .40 both) would work against bear but despite higher sectional density (180gr .400 and 230gr .451 is the same and so is 200gr .400 vs 250gr .451 more or less), the .45 is still bigger with a larger meplat (say .360" meplat on a 255gr WFN .452") and simply weighs more even if it is going 200-250 fps slower (lets say 255gr .45 @ 1000 fps vs 220gr 10mm doing 1200, both from 5" bbl). Sectional density only plays a major role if the lack thereof is preventing it from penetrating adequately. My point is that the end result would be same providing proper shot placement.
 
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The author of the article, a very well known trainer, has changed his mind at least a couple of times, changing from a .45 to a .40 and then to a 9MM.

I'm not trying to defend any particular POV about what caliber is better. I just made the point that the reason people defend what they own is that they already went through the thought process and decided what they thought was best and most people don't change their minds as often as they change their socks. The person who wrote that article might change his mind often but most people don't. They've weighed the issues and made a decision when they bought their gun and most don't see any great need to alter their thinking. Heck I know people who decided that Chevy was better than Ford back in the 50's and they still haven't changed their minds. And I know people who did the same thing only they went with Ford being the best.
 
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180gr doing 1350 is possible from a G20 and that 1300 is possible from a G35
It doesn't matter what is possible out of one certain gun. If that were the question, it would be a coin toss as to what you can get running faster. That's why I say your numbers are off. You can't call it 40SW if it won't run in lots of guns that are made to shoot 40SW. I'm pretty sure your load wouldn't work in my G27. I exceeded its operating parameters limit well before that, using 155 grain bullets.

As for SD, you are leaving out 200 grain 10mm bullets, which most guys worried about bears are going to be carrying.

Indeed, if you were faced with an angry brown bear, I wonder if you wouldn't change your tune. Factory 10mm, factory 45, or factory 40SW? Does it still make no difference? I would rather have gun than none, but I wouldn't go so far as to say I wouldn't care between the three.

I don't expect to see a brown bear up close and personal in my lifetime. So I like em all just fine. But you're the one who asked.

Here's some math:
.452 caliber bullet has a 27% bigger cross section
The 230 grain bullet weighs 15% more than a 200 grain bullet.


But who cares. Cary Grant weighs 1000 times more, and throwing him at a bear isn't going to stop it.
What you should look at is momentum. A warm 230 gr 45ACP at 950 fps (if you can find load data that high, even) has 9.3% less momentum than a 200 grain 10mm load at (looking up hodgdon data here on longshot) 1172fps.

And finally, the 230 grain 45ACP bullet has 9% lower sectional density than the 10mm.

So 9% less momentum and 9% lower sectional density = less penetration, AFAIC.

The 45ACP is bigger. It might make a bigger hole in the bear's hide before it eats you. :)
 
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GLOOB wrote: ...And finally, the 230 grain 45ACP bullet has 9% lower sectional density than the 10mm (200 grain).

So 9% less momentum and 9% lower sectional density = less penetration...

That is the clear advantage the 10mm has over the 40, 200 grain bullet performance. A 10mm has 40-50% more powder space under a 200 grainer than a 40 S&W and still be under max OAL. Add to that MAP is higher for the 10mm @ 37.5K vs. 35K with the 40. Generally a 40 S&W will deliver a 180 grain bullet in the 975 - 1025 fps MV range where a 10mm will give you 1150 fps or more with a 200 and still be under 37.5K.

But the 40 fits in a 9mm size frame and the 10mm will not so you will always be able to find a smaller 40 than you will a 10mm. It is all in what you want.
 
The 10mm is close to being in no mans land. Unless using factory watered down ammo that's equal to the 40 S&W it's too much for SD for a lot of people and it has no real advantage over the 357 magnum for hunting. That's why it's a niche cartridge with a small but vocal and sometimes delusional following. Unless you come across a large pack of angry grizzly bears and you need to unload 3-4 15 round magazines.
 
If size of gun was the real issue then .45 should have been dead about a 100 years ago.
 
If size of gun was the real issue then .45 should have been dead about a 100 years ago.
How many buy 9mm guns rather than .45Auto?

How many police agencies skip double stack .45Autos?

It is a big deal.
 
Well there are many single stack 10mms.

Non LEA use is being discussed.

Where LEA conceal carry is non issue.
 
Well there are many single stack 10mms..

Are there, or are there many variations of the M1911 in 10mm? What are the other single stack designs chambered in 10mm?

Gaston Glock if you are listening, I and others would buy a boatload of single stack G20s if they existed.
 
Well there are many single stack 10mms.
Yep, lots of 1911's available. I'm a 1911 shooter. If I was picking between a 1911 in .40 S&W or 10MM, I'd pick 10MM. If I'm picking between any of the many double stacks such as Glock, M&P, HK, FN, etc., I'd pick a .40S&W. I personally don't need the 10MM's upper level of performance potential and the .40 S&W is sufficient for my needs. For me, the G20 is bigger than I care for while the G22 is still manageable.

To repeat what TestPilot said...
Why is it so hard for some of these people to understand that someof us just want a larger caliber ammo that fits in a 9mm size magazine?

It fits my purpose. 10mm do not. What part of that is so hard to understand?
 
^yes i meant 1911s and sig coming with one as well.

Now how many single stack 45s other than whats mentioned?
 
Not sure if you guys read the original comment. But you would have to have half a brain to think reaming out your chamber for 9x21 IMI is an upgrade.

I suppose you could manufacture a benefit from the longer case by custom loading super light ammo well over SAAMI OAL, maybe in a Glock or a throated 45ACP platform which can feed longer rounds. A regular parabellum case might not hold onto enough bullet in this special case.

Other than that, you aren't going to get any difference by making the case longer and keeping the same OAL out of the SAME gun. It doesn't matter if you are buying factory ammo or handloading. It's the same cartridge only it's intentionally made to NOT fit into a 9mm para handgun. If you can legally own a 9x19, what's the point of 9x21, then? Just in case you accidentally buy a pallet of the wrong ammo? :)
Isn't the 9x21 a work around for countries that don't allow military cartridges for civilians? I didn't know the col is the same as the 9mm luger so that extra 2 mm's isn't even being used. Anyone with their entire brain intact would not consider the 9x21 to be an improvement over the 9mm.
 
Well i can think of more single stack 45's then 10mm's. Sig p220, xds, glock 36, kahr, 4506 and the ruger p90. I think there is more too. But i will have to research when im out of my tree stand
 
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