Posted this in the AR-15 section - thought I would post it here, too.
http://762precision.wordpress.com/2012/02/26/my-new-bear-protection-carbine/




Old and new - .45-70 1886 Winchester Extra Lightweight, Model 71 Winchester in .348 WCF, and Alexander Arms' .50 Beowulf AR-15.


Bear Loads (left to right): .45-70 hard cast, .45-70 JSP, .50 Beowulf HP Brass Solid, .50 Beowulf Brass Solid Spitzer, .50 Beowulf Solid Copper HP (anti-personnel or varmint load), .454 Casull Hard Cast, .45 Colt Hard Cast.