Depends on your definition of Big Bore. If we go with tradition, then I have one, a Verney Carron double in 450NE 3 1/4". If we go by the popular definition, then add 416 Rigby, 405 WCF, 45-110, 375 H&H & 375 Win "Big Bore"....
jorge, I guess that I’m “old school”. For me......”big bores”, start at .40 caliber! memtb