Shooting 40 S&W ammo in a 10mm.
 

Was just BS'ing with one of my work partners and the subject came up of shooting various calibers in certain weapons, such as 38 Spec in a 357 Mag, 454 Casull in a 460 S&W, etc... I then said that I was waiting for my 10mm to show up and the subject was brought up being that it is a 40 cal on steroids and if it is possible to shoot 40 cal ammo in a 10mm? I said that I had never heard of it and am not quiet sure if I would want to expose either of my weapons to such an experiment. Now I am just wondering if anyone else has either heard or tried such and what was the result. I know that the 40 cal is a supported round and expands on the web. Thanks.

It won't work. Both 40 sw and 10mm are rimless cases and both headspace on the cartridge mouth.

Bingo..............

Exactly, unless you happen to have a S&W model 610, which is a 10mm revolver that uses half moon clips like a 45acp revolver does. It does shoot both the 10mm and the 40S&W.

This I know. maybe I didn't clarify what I was meaning.
What I am after is can I shoot 40 S&W in a 10mm in the semi-auto?
Not in any other style or type of weapon like we do with the various interchangeable rounds with the revolvers like the 38/357 and 454/460, etc...

No! The only gun capabile of that is the S&W 610 revolver. Like was mentioned the auto case head spaces off of the cartridge mouth. The 40 S&W is shorter than the 10mm therefor when chambered in a 10mm auto the case will go in the barrel to where the firing pin can not strike the primer, because it doesnt have a rim to hold it from going up in the barrel.

Gotcha. Miss read it. Thanks. I am done.

So in theory, all of the above is correct. No, it isn't reliable to fire 40S&W in a 10mm semiauto because the cases fall too deeply into the chamber (seating on the case mouth).

However, with some models, if you load from the magazine, it WILL fire, at least with reasonable reliability. The extractor picks up the case and supports the rim during firing. So yeah, it fires, but yeah, it also beats the heck out of your extractor (reliability issues in your future).

So sure, it can work, but no, it isn't reliable and it will damage your pistol.

Go for it!

NoMercy is correct...this was demonstrated by the FBI back when they first adopted the Smith & Wesson 1006 / 1076...then discovered that real 10mm rounds were a lot to hang onto...thus the 40 S&W...

In the S&W 1006s, the .40 S&W is supported by the extractor and will fire...no idea about accuracy...there did not seem to be any major damage to the 1006s though the extractor did wear faster... Even they realized that this is not a good idea...

No idea about other 10mm (e.g. Glock or Colt Delta Elite / Double Eagle and clones)...I would not suggest trying it, because as discussed, the 10mm was designed to headspace on the mouth...