Gaffing halibut is one of the simplest things to do.

First check to see if the fish is hooked good. Halibut will remain very calm until their head breaks the surface of the water.

Second, grab the leader and lift very slowly. Have the gaff ready in your other hand. As soon as the head of the halibut breaks the surface hit the crook of their head (the spot where the brown meets the white above their eyeball) as hard as you can with the gaff. If using light leader be careful not to break the leader when doing this. If using anything bigger than 50 lb test you have no problems. Fish over 100 lbs may need to be hit a few times.

Thirdly, lift the halibut into the boat at your leasure as the fish is dead. It may flop a couple more times but this is nothing more than the dead halibut twitch as it now has a brain hemorrage.

Lastly, cut gills!!

In my opinion guns do not belong on boats ecspecially in crowded areas as bullets ricochette off of water and you never know when a wave could knock you off balance when you are pulling a trigger.