Shoot a .380 from a 9mm? Sure No Problem.

dcmdon

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I saw an article recently about shooting a .40 out of a 10 mm glock and how it works flawlessly.

So I was at the range today with my G43, G42, and Kahr P380, and got to thinking. Gee I wonder if I could shoot .380 out of my 9mm glock. So I took the gun apart and slid the .380 up under the extractor and it fit nice and tight. Then I dropped a .380 into the 9mm chamber. The base of a .380 round is a bit smaller than 9mm. But it is about the same diameter up at the bullet. The bottom line is that the case would be well supported in the 9mm chamber.

So i gave it a shot, No problems. The round went off with the case held against the breach by the extractor.

I checked the brass and it was only very slightly bulged. Certainly less than I have seen with some other guns I've owned. The only problem was that the round was not powerful enough to eject.

So I racked the slide, chambered another round from the magazine and it fired fine. Interesting.

So . . any thoughts?
 
I've had a few .380 cases sneak through on reloading my 9mm, maybe four total. They've all done exactly what you just described. They feed and fire fine but you don't get a cycle.
 
I've had a few .380 cases sneak through on reloading my 9mm, maybe four total. They've all done exactly what you just described. They feed and fire fine but you don't get a cycle.

I had one sneak through and it didn't fire. So that makes 4 out of 5 reloaders who say a .380 case will chamber and fire.
 
I had a .380 sneak into my Hi Point 9mm carbine. It went bang....kinda....didn't sound or look right. However, it was able to cycle in the next round. Luckily I was able to stop the shooter before they tried to fire that next round. The bullet never made it out of the end of the barrel. Close call for sure. Sooooo....they may wort of work in a pistol...but a slightly longer barrel is not a good thing.
 
I've had a few .380 cases sneak through on reloading my 9mm, maybe four total. They've all done exactly what you just described. They feed and fire fine but you don't get a cycle.

I've had a few .380 shells sneak into my 9's too while reloading, but since the case head is slightly smaller, the .380 pushes out of the shell plate when seating the primer, so it never makes it to the belling/powder charging stage.
 
How did it shoot (accuracy wise)?

I was able to ring a 1/2 scale steel silhouette from defensive distances. I didn't notice any problem.

When I shot it at paper, I checked and the bullet was not key holing.

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wouldn't the headspacing be off? I wonder if the bullet shears off at all going into the barrel.


It headspaces off the extractor, which holds the round tight to the breech.

I don't know what you mean by bullet shearing. But there isn't any reason for this. Think about how a revolver works. Especially something like a .38 special in a .357 mag cylinder. Or even most .22 revolvers. Lots of free bore.

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And what's the point? To take the chance to ruin your handgun or worse yet to blow your hand off? Please!

The point is "Hmm, I wonder if".

If you think this could doing this could ruin a handgun or blow your hand off, you either didn't read my post or don't understand how firearms work. As long as the gun goes fully into battery, you are fine.

The only questions at hand are
1) will the extractor hold the round securely enough to fire
2) how will accuracy be
 
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http://www.thetruthaboutguns.com/2015/06/jeremy-s/40-in-a-10mm-glock/

Remember that excessive headspace is not a danger in non-bottle necked cartridges.

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I've had a couple of .380 cases that I failed to weed out, get into my 9mm ammo and they wouldn't fire in my M11/9.

I had one sneak through and it didn't fire. So that makes 4 out of 5 reloaders who say a .380 case will chamber and fire.

It depends on the gun. Its all about the ability of the extractor to hold the cartridge against the breach face and resist the forward push of the firing pin.

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I've had a few .380 shells sneak into my 9's too while reloading, but since the case head is slightly smaller, the .380 pushes out of the shell plate when seating the primer, so it never makes it to the belling/powder charging stage.


That's been my experience. I usually catch it on the resizing downstroke, because it feels different, easier, but if I don't on the next up stroke, the 650 advances and it gets pushed out of the shell plate.
 
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You are setting a poor example especially to the younger, less experienced, and new shooters on this forum with your "experiences." If you want to take chances on your own then that's definitely up to you and YOUR choices. But to be pedaling your experimental actions and "thoughts" on this forum is simply not good. It is shooters like you who I am afraid to be next to at the range.
 
You are setting a poor example especially to the younger, less experienced, and new shooters on this forum with your "experiences." If you want to take chances on your own then that's definitely up to you and YOUR choices. But to be pedaling your experimental actions and "thoughts" on this forum is simply not good. It is shooters like you who I am afraid to be next to at the range.
It's a forum not a college textbook. Perfect place to discuss experiences. We already heard your alarmist opinion in your first post a half hour ago.
 
This is one experiment that can harm someone.
New shooters may think you can mix and match calibers like handbags...

Bad JuJu.
 
When I end up with a 380 case mixed in when I'm reloading 9mm they end up pulling out of the case holder when I deprime/resize. They've never made it past this stage for me. Chucked/dropped into the trash can.

I've had a few .380 cases sneak through on reloading my 9mm, maybe four total. They've all done exactly what you just described. They feed and fire fine but you don't get a cycle.
 
I have accidentally loaded my G26 with 380 while at the range with my wife and her BG380. Bang every time; no cycle. I am embarrassed to admit that it took me three rounds to figure it out.
 
When I end up with a 380 case mixed in when I'm reloading 9mm they end up pulling out of the case holder when I deprime/resize. They've never made it past this stage for me. Chucked/dropped into the trash can.

On the Dillon Square Deal they run right through without a hiccup. I usually catch them in the first station (resize/decap) just because the effort goes down and engagement is less on the shorter shell. If I didn't pay attention to that they'd coast right through.
 
On the Dillon Square Deal they run right through without a hiccup. I usually catch them in the first station (resize/decap) just because the effort goes down and engagement is less on the shorter shell. If I didn't pay attention to that they'd coast right through.

Maybe its just tge shellplates, on a 550 with the 9mm plate installed 380s will usually fly out of the press when you try to prime them...

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This is one experiment that can harm someone.
New shooters may think you can mix and match calibers like handbags...

Bad JuJu.

I've done it by accident once, it's probably the least risky one you could pull off, pretty worthless to do it intentionally though.
 
I already posted somewhere about my (well, actually my buddy's standing next to me) experience shooting 9mm out of G23 by accident. The gun fired, didn't cycle, and the bullet hit the steel plate at 25 yards.
 
I already posted somewhere about my (well, actually my buddy's standing next to me) experience shooting 9mm out of G23 by accident. The gun fired, didn't cycle, and the bullet hit the steel plate at 25 yards.

You do realize why this is totally different than shooting a .380 out of a 9mm.

The case diameter of a .40 is significantly larger than a 9. A 9mm case will expand to fill the volume. If it stretches and tears, you have a problem.

A .380 case is nominally the same diameter as a 9mm. So the only diameter that does not the same is length. Since the bullet is designed to release the gasses out the front of the case, this isn't a problem.

This is one experiment that can harm someone.
New shooters may think you can mix and match calibers like handbags...

Bad JuJu.

You are setting a poor example especially to the younger, less experienced, and new shooters on this forum with your "experiences." If you want to take chances on your own then that's definitely up to you and YOUR choices. But to be pedaling your experimental actions and "thoughts" on this forum is simply not good. It is shooters like you who I am afraid to be next to at the range.

Again, if you understand the difference between the calibers, you would see that case failure is not an option. Either it works, or the round doesn't go off.

The case is actually BETTER supported than it is in a .380 because the excessive head space causes it to sit deeper in the chamber.

But if it makes anyone feel better I'll include this disclaimer:
Don't try this at home Kids.

If everyone followed your logic, no wildcat cartridges would ever exist.
I have tools that someone even 20 years ago could not have dreamed of. By using QuickLoad, I could model internal ballistics and was able to see that the very long jump resulted in very very low chamber pressures.

dimensions.jpg
 
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You are setting a poor example especially to the younger, less experienced, and new shooters on this forum with your "experiences." If you want to take chances on your own then that's definitely up to you and YOUR choices. But to be pedaling your experimental actions and "thoughts" on this forum is simply not good. It is shooters like you who I am afraid to be next to at the range.


Actually....what he's doing is being informative and bringing up something many have thought about, if not tried (whether by mistake or on purpose) in the past. I missed the part where he was pedaling anything also. He didn't suggest or invite anyone to try it either.

Jump to conclusions much?
 
I've fired .380 out of a 9mm on a couple of occasions when we had just bought the .380s and weren't being careful enough. It fires fine and I think even cycled once or twice, but don't do it. There's absolutely no point and it definitely could be dangerous.
 
I've had a few .380 shells sneak into my 9's too while reloading, but since the case head is slightly smaller, the .380 pushes out of the shell plate when seating the primer, so it never makes it to the belling/powder charging stage.

I had this happen in my 650 (380 case mixed with 9mm) and it was squirrely at the primer seating but it loaded all the way through. I was looking at it and noticed the bullet seemed high then pulled it. I looked at every other bullet and found another one I didn't notice during loading. So the moral of the story is you may not notice. Good to hear that if it did go into a gun, it would like fire OK.
 
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