If the fish is not swimming properly and lost all its co-ordination then you throw your gun aside as you need both hands to grab it, if it is swimming strongly then of course you keep your gun and have a hand on the line to steer it around if you can and have your associate finish it off. It all depends on the size and strength of the fish, at times I have grabbed the shaft and jammed it into the bottom, or have turned the shaft vertically and had the fish slide down to me. Basically anything that gets your hands on the fish because the longer it struggles the dinner gong is ringing. I have cut some fish heads off while still alive and pulled the heads and guts clear out of the body, that is what that serrated blade knife is for. Unlike spearfishing videos some kills are violent and as the old saying goes, red in tooth and claw, although blood at depth can appear green. A kill knife for sticking in the brain is of the stiletto type, that is all they are good for, but the day I took that photo I did not have my kill knife, although you can see it on another thread.