Great video, thanks. Explains why the new Glock I bought looks almost but not quite like conventional rifling.
Welcome to the community @Stephen369 !
I wonder if anyone has noticed an accuracy improvement with the marksman barrel? I suspect you might have to shoot from a rest to tell the difference if there is enough of one to notice.
I’m still plugging away with my old fashioned Gen 3 
Good point. It would take someone way more expert than a beginner like me to do that.