hello folks
im not familar with these 2 rounds but was told that u could shoot a 380 in a 9mm gun or vice versa. well i may not be to smart on this but i say they are 2 different kind and one wont use the other .
would like to get the brass tack on this before i tell this person he is wrong.

What you can do, and what you should do are two very different things.

It depends on the gun, but some certainly are capable of firing cartridges that they were not designed for. I have watched a YouTube video of a guy shooting 9mm through a 9x18Mak, and they aren't even the same diameter. The gun fired and spit the case out fine, but, the gun essentially fired an overloaded round out of battery.... it is just not a good idea. Unless you are using a Magnum/Special caliber, shoot what the gun says it is chambered for.

Long story short, technically your buddy could be right, but I would find someone else to go to the range with.

Not something that I would do. Two different rounds. Shoot the correct ammunition.
Both headspace on the case mouth. The .380 is shorter and would sit too far into a 9mm chamber in a semi-auto.
Charter Arms WAS to bring out a revolver that was supposed to be able to shoot both, but so far just vaperware.

wyo-man

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The only safe way would be in a revolver using moon clips. Both of these rounds headspace on the case mouth. The 9MM shouldn't even chamber in a 380 and, unless held in place by the extractor, the 380 would drop into a 9MM chamber too far to be struck by the firing pin.

I've heard of revolvers capable of using 38 Super (9X23), 9MM (9X19), 9MM Makarov (9X18) and 380 Auto (9X17), all with moon clips and these should be entirely safe.

The Medusa 47 revolver will shoot just about any round from .355 to .357, including 380, 9mm 38 super, 9mm Largo, 38 sp, 357, and many more.

The .380 and 9mm Luger use the same diameter bullet (.355) but different length cases (9x17mm for the .380; 9x19 for the Luger, and of course powder loads). In all likelyhood, the Luger case would not fit the .380 chamber due to its 2mm longer case. Because the Luger operates at a much high pressure, it would be dangerous to fire it in a .380 even if the tolerances were loose enough to allow it to fit.

On the flip side, the .380 will fit into the luger chamber, and if the extractor holds the case against the breech face, it probably will fire. Still, it's not a good idea to mix ammos and chambers, the exceptings being .38 in .357, .44 Spec in .44 Mag, and the like.

The .38 Spec uses a .357 diameter bullet, and it's doubtful teh .38 case would fit any of the small round chambers. Neither the rimless .380 case or 9mm case would properly fit the .38 Spec chamber. You might get one to fire, but you might also do the same by holding the round in a closed fist and hitting the primer. But do you want to?

The 9mm Makarov is a totally different animal. Its bullet is .365 in diameter, and firing it in any of the above chambers is asking for a disaster. I haven't done a "drop test" to see if it would even fit, but I doubt it.

Don't forget that the 9MM is a taper case while the .380 is straight wall.

So the .380 round might headspace against the taper well enough that the extractor can hold against the firing pin but the case head will most likely be lacking in support. I suspect any .380 brass fired in a 9MM chamber suffers bad case head expansion.

Every time I have accidentally shot a .380 in my 9mm Paraord, it split the case.

I don't do it intentionally, because it risks damage to the extractor. In an emergency the .380 will fire.

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