I have been wondering that myself because i've been wanting a G24. My local gun shop has a G40 MOS in stock and I was thinking of trying to make my own G24 and still have the option of using it as a G40 as well. Since the 10MM and .40 are different length cartridges, I was wondering about the headspace and if it could chamber and feed a .40 into the 10MM barrel. A little digging on the Storm Lake website shows they offer a conversion barrel for using a .40 in the shorter G20(10MM) version, but not one for the longer G40. So i'm just wondering why they feel the need for a "conversion" barrel if what you're saying is an alternative. I know other brands like Coonan offer a .357 Magnum in a 1911 style looking frame. And it can also chamber and fire without issues a .38 Special, which is the same difference to me as the 10MM vs. .40 length-wise. So you're saying you are loading the .40 bullet into the stock 10MM magazine and its feeding and chambering, firing and ejecting from the factory 10MM barrel with no issues?
Last edited by str8_shooter; 01-10-2017 at 08:16 PM.