10mm vs .40 rounds

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Just because 9mm penetrates better in steel and wood doesn't mean it's the better choice for defense. I like 9mm but 40 is better if you want to put the smack down on something. The penetration is less because it is a fatter, blunter bullet. I'm not sure if that would be true for Gel Testing. Alan wants a 10 or 40 and somehow we are debating how 9mm is "better" but I disagree and I have all 3. Really, Alan your best choices are Kimber 1911s and you other choice is a Glock in 10mm. There are no long Slides, no EAAs and no importing of out of production Smith and Wessons!

If you want a 40, the CZ75 is an excellent choice.
 
Thanks for the replies rc and Aguila Blanca

I went down the Ca approved list. It is very limited. I don't want 1911 style, I already have a Gold Cup 45 already. I am not comfortable with the SA cocked and lock for home defense( which is the main purpose for this gun).

I have been calling around in the local area, I was looking at Sig SP2022 40 as it's a DA/SA. I cannot find anyone that has it. I might end up buying a Glock in 45ACP. Glock .40S&W are really modification from 9mm like 23 is just from 19. If I go for Glock, it would be either 10mm or 45ACP as both are from 45ACP frame and slide that are wider than slide of Glock 19/23. 45ACP becomes more attractive, slow fps, less penetration, large bullet for stopping power. Perfect for home defense, better than 9mm. Particular I am limited to 10 rounds, so might as well get bigger rounds!!!

I am less comfortable with Glock compare to Sig 2022 as Glock still something like SA. Now that I have to Glock 26, I know how it works. If I have a choice, I really want a DA/SA like my S&W659. I want to load the chamber for home defense so I don't have to rack the slide when I pick the gun up.

Of cause if I am willing to pay an arm or a leg, I can get HK UPS, but that's a lot of money and I question it's any better than Glock or Sig SP2022. You are talking about over $1000 even without inflating the price.

I am kind of discouraged at this point. I cannot buy one until another 7 days. I might postpone buying another one until more guns are in stock. It's not as if I have to buy one right now. I have my S&W659 like new and fully function I am using for home defense, I just got the Glock 26 and still waiting for ammo to test shoot it. On top, I have Walther PPK in I have to carry it out and I have numerous 25ACP and 22magnum mini pistols. I am by no means short of guns anyway. I hate that one store quoted $999 each for all the Glocks. That's highway robbery. Even the Glock 26 I bought, it's $775 out the door( including tax and registration.

I think all the shortage is temporary, it'll get better sooner or later. We'll see, I have not made the decision. I still have one more store to call, and there are others that are not so close to me.
 
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The CZ was on the approved list but maybe it dropped off the incredible shrinking list. The good news is Allan can still buy a 1911 10mm 1911 and get a 40 barrel to shoot either round.
 
The CZ was on the approved list but maybe it dropped off the incredible shrinking list. The good news is Allan can still buy a 1911 10mm 1911 and get a 40 barrel to shoot either round.
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You do not need a 40 barrel. just shoot the 40 in the 10mm barrel. It is perfectly safe, in-spite of what the safety Nazi's tell you. Just make sure and clean the barrel after shooting 40's.
 
Nanuk said:
You do not need a 40 barrel. just shoot the 40 in the 10mm barrel. It is perfectly safe, in-spite of what the safety Nazi's tell you. Just make sure and clean the barrel after shooting 40's.
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It's safe in terms of not creating a risk of blowing up the gun, but it's not recommended. It means the shorter .40 S&W rounds headspace by the extractor holding the case by the rim, so every shot puts a stress on the extractor hook that it wasn't designed or intended to undergo. It could result in a broken extractor, and that puts the gun out of commission.

Full disclosure: I have done the same thing, shooting .380 ACP through a .38 Super barrel as part of an experiment. I probably didn't shoot more than five or ten rounds.
 
It's safe in terms of not creating a risk of blowing up the gun, but it's not recommended. It means the shorter .40 S&W rounds headspace by the extractor holding the case by the rim, so every shot puts a stress on the extractor hook that it wasn't designed or intended to undergo. It could result in a broken extractor, and that puts the gun out of commission.
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We can go back and forth endlessly. The tool steel extractor is not stressed anymore one way or the other. The case is the same diameter, the bullet is the same diameter. It just adds a bit more freebore. The case is not flopping around. If I ever break an extractor I will let you know.
 
Nanuk said:
We can go back and forth endlessly. The tool steel extractor is not stressed anymore one way or the other. The case is the same diameter, the bullet is the same diameter. It just adds a bit more freebore. The case is not flopping around. If I ever break an extractor I will let you know.
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It's very simple, the casing of .40 is shorter. If you let the bullet slide free into the chamber, it will go all the way in and the firing pin cannot reach the primer. The only thing that prevent the bullet from going farther in is the extractor that hold the bullet against the breach face so the firing pin can hit the primer. So during this process, every time the firing pin hits, the force is asserted solely on the extractor as it's the only thing that is holding the round against the breech face. This definitely put a lot of stress on the extractor.
 
Shoot 40 S&W in a 10mm?

Not trying to prolong a back and forth discussion or argument on shooting 40S&W in a 10 mm semi-auto, but in my eyes unless the manufacturer publishes you can shoot both in the same gun, then one should not do it. I’ve never seen any Semi-auto 10mm mfr state that in their documentation. However the S&W 610 revolver documentation does state you can shoot both in the same gun.

About 3 years ago, I took up reloading as a post-retirement hobby. I’m very wary of Internet forum posts that say “yeah, it’s perfectly safe” to do do this or that beyond maximum load data. Take their claims with a shaker full of rock salt as they aren’t the ones taking the risk when the trigger is squeezed. In my eyes, it’s the same story of what ammo to feed your pistol.

Seems you’re on a gun buying spree, Alan. Me too. Bought three revolvers on my last outing, no monthly maximums here. Wish you could do that too.
Ciwsguy
 
I tried 9mm in my kimber 38 super. The gun shot fine until one slipped past the extractor and it needed to be pressed back out. Just because it can be done doesn't mean it should be done.
 
rc said:
I tried 9mm in my kimber 38 super. The gun shot fine until one slipped past the extractor and it needed to be pressed back out. Just because it can be done doesn't mean it should be done.
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Imagine in self defense situation, the 9mm got stuck in the chamber, you cannot fire it, you cannot extract it, you literally have to use a pencil or a stick to push the round out from the other side of the barrel to clear the jam. That is you have to drop the mag, open the slide, assume you can find a stick to push the round out before you can clear the jam.

I would never shoot a wrong round in a gun.

I would shoot a 38 in a revolver for 357 magnum!!!:D:)
 
It's very simple, the casing of .40 is shorter. If you let the bullet slide free into the chamber, it will go all the way in and the firing pin cannot reach the primer. The only thing that prevent the bullet from going farther in is the extractor that hold the bullet against the breach face so the firing pin can hit the primer. So during this process, every time the firing pin hits, the force is asserted solely on the extractor as it's the only thing that is holding the round against the breech face. This definitely put a lot of stress on the extractor.
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Every time a round feeds it slips up under the extractor from the magazine. There is no stress on the extractor. How much stress in on the extractor during extraction? In a 1911 the extractor is tuned so that it holds a loaded round against the breach face. You are parroting someone else's missinformation.

Don't do it if you don't want to. I know that it works marvelously, it is perfectly safe. Just clean the chamber when done. I know that no manufacturer will recommend the practice as they want to sell you more guns.
 
Not trying to prolong a back and forth discussion or argument on shooting 40S&W in a 10 mm semi-auto, but in my eyes unless the manufacturer publishes you can shoot both in the same gun, then one should not do it. I’ve never seen any Semi-auto 10mm mfr state that in their documentation. However the S&W 610 revolver documentation does state you can shoot both in the same gun.
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They never will. They want to sell you another gun. Mechtech allows for it in their CCU.
 
Nanuk said:
Every time a round feeds it slips up under the extractor from the magazine. There is no stress on the extractor. How much stress in on the extractor during extraction? In a 1911 the extractor is tuned so that it holds a loaded round against the breach face. You are parroting someone else's missinformation.
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It's not misinformation, and it's incorrect to say "There is no stress on the extractor."

Assuming the extractor is working properly and the round feeds normally, sliding up into the notch behind the claw rather than snapping over the rim, in the case of firing the correct cartridge for the firearm the case headspaces on the case mouth so at the moment of ignition there is no longitudinal stress on the extractor. After firing, if the gun is properly timed, extraction should occur after the empty case has shrunk back somewhat from its maximum dimension, and has released its hold on the chamber wall. Axial stress on the extractor is minimal.

In the event of shooting .40 S&W in a 10mm barrel, the case mouth doesn't reach far enough into the chamber to seat against the ledge, or step, at the front of the chamber. This means that, as Alan wrote in post #108, "The only thing that prevent the bullet from going farther in is the extractor that hold the bullet against the breach face so the firing pin can hit the primer. So during this process, every time the firing pin hits, the force is asserted solely on the extractor as it's the only thing that is holding the round against the breech face. This definitely put a lot of stress on the extractor."

How much force does this actually amount to? I don't have a way to quantify it. It's going to be a function of many variables. It is NOT going to be zero, however, and I'm pretty certain that it's more than the force required to simply extract an empty case of the proper length from the chamber.

Can it break an extractor? Yes, it can ... in fact, I have read reports where it has broken the tip off an extractor. You can argue that the extractor was probably defective, and I wouldn't dispute that. That doesn't mean the extractor didn't break. Even defective extractors don't break under zero force/stress.
 
Profiles are meaningless. You can write anything in there and say that you’re God, but I certainly wouldn’t believe that.
 
OK, I have a little time to do some measurement on 45ACP fitting into my Colt Gold Cup and 9mm into my Glock 26. This is what's happening with a shorter casing fitting into a gun that fit the longer casing but same diameter rounds.

I don't have a gun to measure on .40S&W and 10mm, you guys can try it.
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You can see if Fig.1 I measured the 9mm and the 45ACP casing. The diameter of rim (a) and the last part of the casing(b) is very close. I open both my Gold Cup and Glock and I can fit the round the OPPOSITE way with the rim of the casing going in first. I can at least partly fit into the chamber. This means the rim can go into the chamber if the casing is too short.

Now look at Fig.2, the normal way of how a round is loaded into the chamber. The diameter of the chamber is larger than the barrel, so the casing is STOPPED as shown in Fig.2. This is true for my Glock and Colt Gold Cup.

Fig.3 show what happens if you try to fit a short casing 0.40S&W into a 10mm chamber. Since the casing is shorter, it will go all the way in until it hits the end of the chamber where the diameter becomes smaller.......unless something is holding it in place against the breech face. Without that, the firing pin will NOT hit the primmer and the gun won't fire.

Fig.4 The only way you can fire a .40S&W round is something is holding the round against the breech face so the firing pin can reach and hit the primmer to discharge the round. The ONLY thing that hold the shorter .40S&W in place is the EXTRACTOR. So when the firing pin hits, the strike force is asserted completely on the extractor that is hold the round against the breech face.

This is NOT about experience, this is about science and engineering.

I can say for sure both 45ACP and 9mm works exactly like what I described. This is the same if you try to fire a 380 in a 9mm gun. That will stress the extractor. You guys can do the same measurement like I described if you have the 10mm gun and .40S&W rounds.

With extractor of Glock made of MIM, you'll be taking a big chance. If it is made of forged, then it might be better, but I still won't do it.

Hope this help.
 

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I am not saying anything about the person. I am concentrating on the science. That's it. measure the rounds, reproduce what I did and see. If I am wrong, I am wrong. I am not here to argue. It's about science and engineering.

I can say with confidence this hold true for 45 and 9mm. and I can say for sure this is going to happen if you try to shoot a 380 in a 9mm gun. It's up to you guys to do the testing on .40.

It's easy, take the 10mm barrel out, fit a .40 round, if the rim drop pass the mouth of the chamber, you know the extractor is taking all the stress from the firing pin hitting.
 
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