I was one of the first to buy the Marlin 450 Guidegun, hunted Rangley Maine on a baited bearhunt, used Hornadys 350gr interlock FP in front of 50gr H4198, CCI mag primers, lee factory crimp(Heavy) 2180fps.
i shot the bruin at 45 yards, took him off his feet, the shot placed right behind the shoulder as the front leg went forward, went in like a .458 dia and came out like a silver dollar and dump all his innards onto the ground, I was shocked to see that, I can't believe got up and ran sixty yards and dropped, trying to get back up i coop da grass using my SRH 44mag, i was impressed with the power of the 450 guidegun, I would use it on any North American big game without any hesitation, the bruin dressed at 250Pd's, very old bear I was told, teeth were worn pretty well.
In all the Marlin 450 performed well, sometime those blackys just have a great will to survive and don't die easy. Aim small hit small. RAMbo.