Interesting read, and what a savings for you. I checked ammo prices at Turner's, a chain in So CA. They have only one .38 Super ammo listed, Winchester White Box FMJ 130 grain Plus P @ $32.99 for box of 50. In 9mm their closest Winchester White Box as above is $17.99 box 50. In total they have 3 pages listed of all 9mm.

 

Can and should are two different things. .38 O.A.L. 1.280, 9mm 1.169. The .38 is a semi rimmed straight wall case . The 9mm is a tapered rimless case. The 9mm headspaces on the case mouth. The .38 headspaces on the rim. Pressure is less in the 9 and bullets are the same diameter. One day you might not get away with it. But, if you enjoy risks, fire away! Heck, while you're at it , try a .380 in a 9mm Makarov . I "should " work too.

 

The .38 is a semi rimmed straight wall case . The 9mm is a tapered rimless case. The 9mm headspaces on the case mouth. The .38 headspaces on the rim.

The idea that the 38 Super headspace on the rim only true anymore if you have a very old barrel, all recently made barrels headspace on the case mouth.

And yes, you can shoot 9mm ammo in 38 Super barrel MOST of the time, if the chamber of your barrel is not extremely match grade tight. BUT you should not do it too often, it will shorten the life of the extractor, because that is what holding the 9mm round in a 38 Super barrel.

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Kilibreaux - a .380 can be fired out of a 9mm AR; but shouldn't be done. Some .38 Special revolver cylinders are just long enough that you could, but shouldn't shoot .357 Magnum out of them with more then likely disasterous results.

I've done the .380 out of a 9mm AR one round. As soon as it went bang I knew it. I was lucky - the empty casing was extracted and ejected but I knew something was different - the bore was clear. No apparent damage so I after I removed the unfired rounds from the magazine and didn't find any other .380 rounds, I went back to shooting.

Although it has been working for you I think you've been real lucky; other people who have shot the "wrong" ammo out of their guns haven't been so lucky. The following rounds are very similar in size, by a few milimeters but could be disasterous if shot out of the wrong gun: .38 acp; 9mm, 8mm Largo, .380 acp, .38 Super. Almost all .38 Super ammo is marked +P; to warn those who have pistols chambered in .38 Auto not to use the Super round in their guns. The rounds are almost identical - until you look at the ballistics and see that .38 acp is a very mild loaded round when compared to .38 Super. Many beautiful older .38 acp pistols have been destroyed, often causing injuries to the shooter when the gun blows up.

Although you can shoot 9mm in your .38 Super you shouldn't. There is some 9mm ammo, made by Hirtenberger, that both the manufacturer and BATFE jointly wrote a letter advising everyone to not shoot that ammo out of any pistol - it was designed and loaded for sub-machine guns being used in Arctic conditions...it is like +P++++ hot.

 

I imagine that there a lot of things that "can" be done.

I value my firearms and body parts too much so I avoid the "can" do things

 

I'd play with it on the bench a little to see what is going on.
9mm MIGHT be headspacing on the extractor in the longer chamber.
OR it MIGHT be seating on the taper of the case wedging into the cylindrical .38 chamber.

Neither is particularly harmful, but, if the 9mm should ever get ahead of the extractor and down all the way to the chamber mouth, the uncontrolled firing pin protrusion of the 1911 design will still fire it and, as Maj George C Nonte showed with the Astra 400 (any 9 gun), fireworks will result.

 

What was the gun?

 

This was simply dumb luck and you shouldn't encourage anyone else to try this on their pistols. I accidentally shot a few 9mm rounds from my 38 Super Elite Professional and the slide locked up so badly that I nearly had to send it back to Wilson Combat.

 

Just curious, what was the cause for the lock up?

 

Not that's it too germain to this topic but Armscor .38super is dramatically waterdown, kinda like the 10mm of today that is barely more than .40S&W velocities.

 

You can also chamber and fire a .40 S&W in a .45 ACP and a 9mm in a .40 S&W and you can enter the freeway going in the wrong direction!

Ask me me how I know this, just see my sinature line.

 

If you want to shoot 9mm, then why not shoot it outta a 9mm handgun? What am I missing here? This makes absolutely no sense.

Rick