I checked around and this story has been posted to different forums in the past.

http://siloutdoors.com/showthread.php?t=80

http://blogs.aviation.ca/index.php/steve.php/2006/10/29/my_favourite_hunting_story_2006_the_long

Here is probably the most detailed version from an Anchorage New site.
http://dwb.adn.com/outdoors/hunting/story/8632924p-8525255c.html

I too might suspect why they left their rifles behind. But having quartered and packed many elk and one moose a long ways out (how many whitetail hunters know that routine?) of the middle of nowhere, you tend to want to travel light and that can get in the way of thinking about self preservation.

Even if they sold everyone a BS story to cover killing a bear, it is a good read.