It is true, adapting a 9 into a 40 creates problems. But, some guns were later designed around the 40. The 40 S&W M&Ps are easy to shoot well.
I don’t know why this comes up in the SD/Tactical conversations. Why must there only be one? 9mm or 45 or 40 or 5.56 or 7.62, etc. There are at least 10 viable factory 30 caliber hunting cartridges that all work.
