Ya, I wern't born last night, just curious!!😁😁😁
I have never owned a 10mm but my semi educated guess to that question would be NO! The reason for that answer is only a guess BUT since both the .40 and the 10mm are rimless cases, don't they headspace on the mouth of the brass? If my thinking is so, then wouldn't the .40 S&W cartridge drop down about a quarter of an inch into the chamber of a 10 mm.
As I noted above, the case is .147" away from the correct headspace. Over an 1/8 of an inch off - That's a big gap!On a round that is designed to headspace on the cartridge case mouth there is of course step up or ledge in the chamber that the case mouth should set firmly against. With the firing of a shorter cartridge that ledge is subject to flame cutting or erosion. If done enough you will compromise the function of the pistol when used with the cartridge it was designed to use.
Yup, me too.I was only speculating about 10mm because I once owned a .357 Magnum and usually shot .38 in it at the range for cost, of course. But when I stored it loaded for defense I'd load it with JHP .357 rounds. I thought about having the same kind of flexibility between .40 and 10mm, but clearly it's not the same thing. I have a G27 and love it, and I would only ever buy a G29 (or any other 10mm) if I could run .40 through it.
I don't think I'd ever want to use 10mm as a defensive round (overpowered for defense use and way more recoil than .40 or 9mm). I just thought it might offer the versatility of using 2 kinds of ammo in a single firearm (much like .38 and .357, or being able to fire .22LR in a .22 Magnum). But from the responses in this thread AND from a reply I got from the Glock support team, the answer is an emphatic NO, do NOT fire .40s&w rounds in a 10mm Auto gun. So I'll keep my G27 and put any thoughts of 10mm out of my mind.