Hello, I was told I could buy a G31 & swap the barrel with a g22 barrel & then use G22 mags & I'll be able to have a G22 basically. Is that the case? And would it be reliable. Here's the deal. I want a G22, but a friend has a used G31 for sale cheap. For less then a new G22, I could buy the G31, .40 barrel & a few 22 mags & then have .357 & .40.