well .. we would rather see you not hunting while scuba diving ... not much sport in that....
But just to answere some of your questions, a fish that size must wiegh close to about 50 + Kg .... if you got no reel ... or float system, its very likely that you would end up loosing your gun.
If you decide to hold on to your gun ,,, there is i high chance the fish will drag you about for a while and in the process knocking off your regulator. Now that could get ugly at that deapth.
Shooting it at 45 m ... you will definatly spend about 15 min to get the fish under control,,,, that if you still have the gun in your hand and the reg in your mouth.... will you have enough air to do your deco stop!
best option is have a reel on the gun as well as a lift bag + or a float on the surface with 50 - 60 m line.
i woudl recomend you try to stone the fish in the first shot - thats if you are confident and have an accurate shot...
best oftion.... use chum lure the fish to the surface about 15m or so ,,, free dive and take your shot -
Good luck in what ever method you choose to follow!
Nesim
