Tom, I did a 8' brown bear several years ago with my Taurus Raging Bull .500 S&W at 129 yds. with a 375 br. Barnes X. He dropped and was dead. My guide insisted I put another one in him, but it wasn't needed. The X is a fantastic bullet for heavy game. Getting ready for this hunt I took several deer with this combo out to 150 yds. All were 1 shot.
Not handloading makes it a little more difficult. 350 XTPs are definitely NOT good bullets for much of anything.
email me at wvhitman@frontiernet.net and we can "talk" a little more.
Larry