Carry a .22 for ptarmigan. I also use the machine for caribou and moose hunting. The boot lives on the machine.
We use a .45 on a bump stick for shark, and that barely slows them down.
Here are some pics of salmon shark fishing out of Valdez, Alaska.
Click for fullsizeThis guy chewed off the anchor rope
1000lbs of meat off of these guys
Me fighting one
Use 1/8" steel leader for these teeth