My buddy owns a 9mm Shield and I own a 40 cal. Shield. We were cleaning our guns and got the idea of swapping out the barrel of my 40 with his 9. Guess what it fix perfectly, exact same fit as the 40. Loaded up a 9 mm magazine into the 40 and successfully manually loaded and ejected every round flawlessly. We weren't at the range so I can't tell you how it shoots but I can see no reason what so ever why it would not.
My question is has any one tried this and what were the results?