It does not look like this was well followed , well over 2 year old post...
and the number at that time seem low... in particular Stoeger , TTN , and 97's Originals or replica's.
just a observation ... but I truly believe 12 Gauge is far and away the leader.... 20's next , 16's lag way back , and 10's almost never seen ( I said almost ).... 8's just once and he did not shoot it just, showed it....
In my home , NCOWS Posse' I can account for having seen used at least 5 TTn's , as many & more Stoegers, 1 Rossi.
many 97's mostly originals , and 3 Century's... I recall a few Baikal ( they were rather common as the importer is just 40 miles over on the coast.....
and several Fox , 311 etc.
nothing scientific here just my casual observation...