I thought it would be educational to try this...Below is a pic of my GT modified Mec-Gar mag with a 30 Mauser in it...It won't go down any further...The spring keeps pushing it up...I can't fit it into the Luger because the bullet nose jams on the magazine release (or on the edge of the mag release hole)...
I don't get YouTube here but as Vlim says, that Luger (*IF* it is firing 30 Mauser rounds and not 30 Luger rounds) has been modified beyond just re-chambering...A custom follower with a steeper angle might work...I suspect the chamber rim would need tweaking too...
But if you're really interested, I have a 30 Mauser chambering reamer and would be happy to ream your Luger barrel to take the Mauser cartridge...then you could buy some steel case Tokarev ammunition and have a real vest penetrator!!!
