My favorite BIG Bore for everything but the largest of brown bears is the 45-70 loaded with 405 gr bullets over 3031! For Pa black bears that can weigh up to 800# it is devistating. I've killed bears in Pa over 600 # (2 of them)using a Marlin 1895 and I can not imagine any caliber that would do a better job of it. Why would anyone not consider a .45 caliber bullet going near 2000fps a big bore? BB