Could I/Should I shoot .380 ammo out of a S&W 940 9mm revolver with moon clips? If not, why not? Please advise. Thanks!

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otis

Your gun, so feel free. However, just about every dimension of the case of a .380 ACP cartridge case is different than a 9mm Luger cartridge case. Plus you've got the added free space the bullet will travel before contacting the forcing cone. I don't see any upside in it, and a few ways you'll get cracked cases.

Besides that, 380 is more expensive than 9mm

I think Taurus offers a revolver chambered for 380.

As Borderboss stated the case dimensions are very different...... The most critical being that the specs call for a 380 case head dia. of .374 versus a 9mm case head dia. of .394.......... You are certainly going to see the case swelling just above the base and some risk of case ruptures at that point. If they just swell no big deal (so long as you don't want to reload them) but if they burst you're going to get a lot of gas dumped out at the breech............. Outside of an "end of the world, all you can find" situation I see no reason to even consider it.

Thanks for the input everyone!

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otis

Have seen it done in a Beretta 92F many years ago. I friend had a friend who worked for a reloading service in Orange County, Ca. He gave him a bunch of blemished rounds in 9MM to shoot. Somehow a .380 got in the batch. It fired, but failed to extract. So wound up with a jam. Would not recommend it as a regular sort of thing to do.......

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USMC 69-93 Combat Pistol Inst.

More than anything the rim is smaller and the case shorter than 9mm. The .380 will be un-supported and fall too far into the 9mm chamber and the firing pin would not reach the primer to fire the cartridge. The other objections cited by are others above are valid too!

There are ca. 24 different auto pistol cartridges that are designated as 9mm. While some of these are just different names for the same cartridge there are none interchangeable with the 9mm Parabellum because of dimensional differences.

On a revolver probably. On an auto it will fire. As I stated have seen it happen.

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USMC 69-93 Combat Pistol Inst.

Been covered before in this old thread:

.380 ACP in a 940? Why, yes! Yes, you can.

An acquaintance of mine used to run the range program of a major SoCal police department. The were looking for a way to induce failures SAFELY with their 9mm service pistols for training purposes. They found that firing a .380 in a 9mm in all their test firing NEVER left a bullet in the bore but would produce failures reliably. They found it to be a reliable training aid.

I guess you could call what I described before as a "training aid". The .380 in question was mixed into a bunch of 9MM. It got loaded into the Beretta's magazine with the 9MM's. The .380 round cycled into the chamber normally and fired. Then as the case was jammed into the chamber it would not extract and caused a jam of the weapon. After clearing the weapon and continuing the shoot, we counted the shot holes in the target and had a hole for each round fired including the .380.

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USMC 69-93 Combat Pistol Inst.