[Alan Fud]

... shoot .40S&W ammo out of a revolver chambered for a 10mm?

... shoot .380ACP ammo out of a revolver chambered for a 9mm?

[Brian Williams]

I know 40 in a 10 but looking at the 380 dimensions vs the 9mm????


380 9mm
rim dia .374 .394

case diameter
rear .374 .391

mouth .373 .380

bullet dia .3565 .3555


there is a .02" in dia difference in the rear of the case would bulge the 380 alot and would over time and reloads would cause them to weaken and split

Safely ??????

scroll to bottom of each page and you will find a drawing of each case

http://www.reloadbench.com/cartridges/p9lug.html
http://www.reloadbench.com/cartridges/p380acp.html
http://www.reloadbench.com/popup/cart/188.jpg
http://www.reloadbench.com/popup/cart/329.jpg

[tiberius]

NO, neither will headspace correctly. These cartriges all headspace on the mouth of the case.

If you have an auxillary cyliner made, then they will work fine.

[Longbow]

I know .40 cal will work on 10mm wheelgun. I know someone in my club who does it all the time. I don't know the long term effect on the gun, though. Chamber erosion?
I've fired .380 case w/ 9mm bullet (reloaded the @@##*** thing accidentally) on my Glock 17 w/ no ill effect on the gun, except it won't cycle. Well...okay that's an ill effect!:D

[tiberius]

Of course I forgot about moon clips:o

[Jim March]

If the revolver uses moon clips, no problem. Usually. There's a caveat though:

Some moon-clip guns will still work OK without the moons, as there's a lip down in the cylinder bore that will retain the shell just as an auto would. With such guns, the only real reason for the moons is fast loading, and ejection - with no moon, you'd have to knock rounds out with a pencil or something as there's nothing for the ejector star to grab. Spotting the lip is easy, just unload, swing the cylinder out, shine a flashlight in there and look :).

If your wheelgun is set up that way with a lip, say, in 10mm, you can shoot 40s but they'll knock against that "10mm lip" on the way down the cylinder bore. This will deliver a destabilizing blow to the projectile which is no good for accuracy, and if it happens too much it'll ding up that square lip edge.

Solution: if I had a 10mm gun with that lip, and a good supply of the moon clips, I'd consider having a gunsmith convert that "lip" to a gentle slope down to the restriction at the end of the cylinder bore. This would increase accuracy with 40s, relieve that "beating" the cylinder would otherwise get, and the sole cost would be that you could no longer shoot 10mms without moons.

Not all moonclip-based guns have such a lip. It'll be dead easy to spot. If it's not present, then yes, you can shoot shorter calibers just fine, although the optimum dimensions for the 380 are just enough "off" that accuracy might be squirrelly in a 9mm.

No such problems with 40 in a 10mm though.

If the revolver is an SA with no moons, the "lip" is all that retains the shell (headspaces the round) so a 40 will drop way too deep in a 10mm cylinder to fire. The only way to get a single SA cylinder to fire multiple calibers is the weird aftermarket "Medusa-type" cylinder. But it's cheaper just to set up multiple conventional cylinders.

[Mike Irwin]

You'll need to moon clip the .40 S&W rounds so that they don't drop through the cylinder, but I know a couple of people who do this with their S&W 610s.

As for the 9mm/.380, no. The dimensions aren't right.

[355sigfan]

I shoot 40's in my 610 and they work fine. But they are less accurate.
PAT