My google foo isn't up to par with some of yours..
I am hoping to get a list of bore sizes for as many semi auto 12s as possible from various mfg.. Clark helped me get a few of them down.. If you can add to the list please do, especially the Franchi and Stoeger guys. Also correct any problems that you may see.
Benelli Vinci/SBEII/Berretta..............724
Remington......................................735
Winchester......................................738
Browning invector plus .....................742
Mossberg.......................................775