That no one makes a decent production 1911 in .40 (or even better in .357 Sig)?
Some folks make 1911 pattern firearms in 9mm (Warthog and such) but unless you are willing to shell out Big Bucks, there are no decently priced 1911 s in anything but .45 ACP. And nearly nothing in .40 or .357 Sig.
I'd guess overall cartridge length. Based on the .40 1911s I've seen the .40 is so much shorter than the .45 that if you don't use magazines with built in spacers you get a jam o'matic.
Buy a Delta Elite and load it with 10mm lite. I did. 😀
might have to consider that!