I'm confused .40 or 10mm

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Surplus nut

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Ok, I know I'm going to catch a lot of flack for this one. I have been a collector and shooter for quite some time(surplus is what I stick to mostly), but seem to be confused. Is there a difference between 10mm and .40 cal? I thought they were the same, but know have some doubt.

I am very interested in getting a nice handgun, preferably a sig. I have been trying to research a little. I was hoping to cash in on the sig's that you can get the .40 and .357 sig barrels for the same gun. I figure that would be the most practicle. I am also confused because I keep finding Sigs I like, but they seem to have a polymer frame. I only want to get a metal frame I think. Does anyone know what model Sig would be best?

Thanks for any advice in advance.
 
Here's the thing 10mm has a longer case than .40 S&W, in fact it came out before the 40. Depending on the gun it can be very dificult to upgrade from the 40 to the 10mm, however it is almost always (from my experience which. . . take it or leave it) to downgrade from 10mm to 40. or .357. Generally all you need is a new barrel, recoil spring and magazines. As far as Sig goes I know of only one model you can switch around like that a Stainless Sig P220.
 
10mm Bullet weight/type Velocity Energy
135 gr (8.7 g) Nosler JHP 1,600 ft/s (490 m/s) 767 ft·lbf (1,040 J)
155 gr (10.0 g) Gold Dot HP 1,475 ft/s (450 m/s) 750 ft·lbf (1,020 J)
165 gr (10.7 g) Golden Saber HP 1,425 ft/s (434 m/s) 744 ft·lbf (1,009 J)
180 gr (12 g) Hornady XTP 1,350 ft/s (410 m/s) 728 ft·lbf (987 J)
200 gr (13 g) WFNGC 1,300 ft/s (400 m/s) 750 ft·lbf (1,020 J)

.40 Bullet weight/type Velocity Energy
135 gr (8.7 g) Federal Premium JHP Low Recoil 1,190 ft/s (360 m/s) 424 ft·lbf (575 J)
155 gr (10.0 g) Speer Gold Dot JHP 1,175 ft/s (358 m/s) 475 ft·lbf (644 J)
165 gr (10.7 g) Speer Gold Dot JHP 1,150 ft/s (350 m/s) 484 ft·lbf (656 J)
180 gr (12 g) Speer Gold Dot JHP 985 ft/s (300 m/s) 400 ft·lbf (540 J)
200 gr (13 g) Double Tap Hornady XTP JHP 1,050 ft/s (320 m/s) 490 ft·lbf (660 J)

As said, the .40 was the lower energy development in the US in response to the original 10mm. An anemic version of the 10mm
 
The bullet diameter for both .40 cal and 10mm is .400". The FBI wanted a new cartridge to outperform the 9mm after the FBI shootout (in Florida I believe), and the 10mm was born, however the 10mm is a VERY hot round, and a lot of the agents couldn't handle the recoil and had hard times qualifying on the range, so the case was shortened to what is the .40S&W to be a powerful yet more controllable round. And I'm not an expert on this and hope my information is accurate.
 
To attempt to answer your question; think 38 special vs 357 mag, it's a similar situation betwen the 10mm and rhe 40 S&W rounds. The 10 mm Auto cartridge was a proprietary cartridge developed for the ill fated Bren Ten semi auto pistol. Shortly after this cartridge started to catch on, since it was a semi auto round with performance close to the 41 Rem Mag and when Colt chambered their 1911 for this cartridge as the 10 mm Delta Elite it became rather popular back in the 80's . Well the FBI liked the this cartridge, adapted it and Smith and Wesson came out with several semi autos for it. Unfortuantely women and men with small hands had difficulty handling this powerful round in the large framed semi auto's. Therefore S&W and Winchester developed a cartridge less powerful and that could be used on the small 9mm semi auto frame instead of the larger 10mm frame. While both cartridges use the same .400" diameter bullet, the cases are not interchangeable. The 10 mm case is longer and thicker, and uses large pistol primers, the 40 S&W is shorter, less powerful, and uses small pistol primers. However you may reload both on 10 mm dies since the case O.D. is the same. The 40 S&W is extremly popular with LE people today the 10 mm round has faded out and has become almost a cult cartridge even though several companies still chamber their pistols for the 10mm, namely Colt and Glock plus a few others. The 10mm round is an excellent cartridge and one of my favorites. :)
 
The obvious differance beside power is:
The .40 S&W is short enough to fit in 9mm frame/magazine size guns. (1.135" Max OAL)

The 10mm is enough longer to require a .45 ACP frame/magazine size. (1.260" Max OAL)

That makes the 10mm better suited for people with bigger hands.

The .40 S&W better suited for unisex police forces, etc.

rc
 
Is there a difference between 10mm and .40 cal?

Yes.

HUGE difference.

You can hardly find 10mm ammo anywhwere, and when you can, its usually PREMIUM ammo at sky-high prices.

10mm makes no sense at all unless you are a handloader, or if you almost never shoot.

By comparison, .40 S&W is widely available, and can be had for only about 30% more than the cost of comparable-quality 9mm ammo.
 
Yes... there is a difference. The 10mm in its full-power loading beats the .40 in both bullet weight and velocity. Does this power difference matter against a 2-legged predator? Who knows. But it makes a great woods load for bigger beasts. Here is some testing that compares the two. The .40 is shown towards the bottom of the article.

http://brasstard.com/?p=225

10mm is a great load, and if you buy a Glock 20/29 you can fire cheaper .40 with a simple barrel swap.
 
Yep, 10 mm handgun owners claim the "S&W" in .40 S&W stands for "Short and Weak". But they do shoot identical projectiles, just 10mm a lot faster.
 
An interesting article on Wikipedia about the history of the .40 S&W's history can be found here.
 
^^^^
That really says it all. Very worth reading. FWIW, I like .40s...

Les
 
Both use a .400" caliber bullet. (Technically, neither are a true 10mm caliber, which is .394". :neener:) The .40 can fit into a medium- or even small-frame pistol, being the same overall length as the 9mm Luger. The 10mm Auto, because of its length and original full power loading, generally needs a large-frame pistol. Even the compact Glock 29 is very thick and "chunky." To complicate matters further, the 10mm is offered in a full power and medium velocity load, the latter of which virtually duplicates the .40 in power, and some .40 loads are pretty hot, approaching the full power 10mm. :confused:
 
Only 2 SIG pistols to really choose from IMHO P229 and my favorite the SIG P226 .40S&W / .357SIG. No tupperware guns all metal. I recommend the SIG night sights and skip the rail if you can for no other reason than I don't like rails on pistols, make a good ugly SIG look uglier. I have 5 SIGs none polymer, Glock, H&K and FNH for plastic, again just an opinion. Get a P226 if it's not for carry or the versatile P229 if you intend to. Lots of info on the referenced calibers but none on the choices of firearms, P250, P2022 both polymer frame, P226 is perhaps the best pure weapon ever made. Get one in .40 and a replacement barrel in .357SIG for around $180.
 
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The obvious differance beside power is:
The .40 S&W is short enough to fit in 9mm frame/magazine size guns. (1.135" Max OAL)

The 10mm is enough longer to require a .45 ACP frame/magazine size. (1.260" Max OAL)

That makes the 10mm better suited for people with bigger hands.

The .40 S&W better suited for unisex police forces, etc.

As is usually the case, RC wins the thread. Size, not recoil, is the primary driver behind the .40 S&W developement. Being able to have a more powerful service round (than a 9mm) in a high cap 9mm sized frame was the objective.
 
A semi-related question:

I've mostly seen .400 caliber bullets sold for .40 and 10mm. I would think given the velocity difference between the two rounds, loading the .40 bullets for 10mm might cause expansion problems in hollow points. Anyone know about this?
 
The only Sig in 10mm is a Grey Guns P220 conversion (expensive and 6-9 months wait IIRC). I'm sure Grey does a good conversion, but the first batch were recently shipped and it's unproven IMO.

Colt, Dan Wesson, Kimber, Springfield, Fusion, STI and others make 1911s in 10mm. (DW is not making any 10's this year). Glock and EAA offer 10mm guns. The Glock or Colt Delta Elite are probably the best starting points unless you can find a 2009 Dan Wesson. The EAA is the most economical and a lot of people like them.

A lot of 10mm ammo is downloaded to not much more than 40SW. BUT some of it is full power and a lot hotter than 40SW.

Sig makes plenty of all metal guns. P220, 226, 228, 229, 232, 238, 239. The P225/P6 is also available as used European police imports.

Ken
 
The EAA is the most economical and a lot of people like them.

Let's not forget that the EAA Witness, at least in its basic form (the standard Wonder Finish with the new style rounded top slide) it is not a "true" 10mm handgun...it can only take the "FBI lite" loads (the vast majority of commercial 10mm ammo in the market)

No Corbon, Double Tap or Buffalo Bore...penalty is cracked slides even with stiffer springs (personal experience)...EAA is adamant about this....it is impressive to see the difference in heft and construction between a Witness and my S&W 1006.


On top of that I rather spend more for a different pistol than facing the possibility of dealing with EAA.
 
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The 10mm is a fantastic round, a true magnum cartridge for standard recoil operated semiauto pistols.

However the 40 S&W is the most successful modern handgun cartridge ever created and there are very good reasons for it...45 ACP performance (or superior in many cases) in 9mm size and magazine capacity handguns.

My carry is 10mm in the woods and 40 S&W in the "urban jungle"
 
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