Dummies guide to Spearfishing - Part II by Ismail Sonday on DeeperBlue.net - Fanatical About FreeDiving, Scuba Diving, Spearfishing & Technical Diving

Gun size is dependant primarily on the visibility in your area. Generally, the cleaner the water, the longer the gun. Then there are also guns that are used for very specific purposes, such as a 75cm gun that is used for hunting in caves, cracks or crevices. Here, smaller guns maneuverability gives it a great advantage over a longer gun, even though the water might be very clean. The following is just a general idea on what gun sizes you should look at. The easiest way to find the ideal gun size is to simply speak to the succesfull spearo’s in your area.

Viz	Blue Water Diving	Reef Diving	Kelp Diving	Cave/Hole Diving
15m+ 50ft+	130 cm	120 – 130cm	60–90cm	60 – 70cm
10-15m 30–50ft	120–130cm	120–130cm	60– 90cm	60 – 70cm
5-10m 15–30ft	110–130cm	110–130cm	60– 90cm	60 – 70cm
0-5m 0-15ft	110cm	90–110cm	60–90cm	60 – 70cm

Viz	Blue Water Diving	Reef Diving	Kelp Diving	Cave/Hole Diving
15m+ 50ft+	63 in	60-63 in	55-60 in	44-50 in
10-15m 30–50ft	60-63 in	60-63 in	55-60 in	44-50 in
5-10m 15–30ft	55-60 in	55-60 in	55-60 in	44-50 in
0-5m 0-15ft	55 in	55 in	55 in	44-50 in

Viz	Blue Water Diving	Reef Diving	Kelp Diving	Cave/Hole Diving
15m+ 50ft+	63 in	60-63 in	55-60 in	44-50 in
10-15m 30–50ft	60-63 in	60-63 in	55-60 in	44-50 in
5-10m 15–30ft	55-60 in	55-60 in	55-60 in	44-50 in
0-5m 0-15ft	55 in	55 in	55 in	44-50 in

Hopefully you have now successfully navigated the minefield of spearguns and should be able to make a good decision on what type of gun and what length would be suitable for YOUR application.