Speargun

A speargun is an underwater fishing implement designed to fire a spear at fish or other underwater animals or targets.

The basic components of a speargun are a spear, a stock or barrel, and a handle or grip containing a trigger mechanism. Spearguns are usually from 0.5 to 2 m (1.6 to 6.6 ft) long, round or roughly rectangular from 28 to 75 mm (1.1 to 3.0 in) in diameter/width.

The two most common types are:

Rubber powered ones come in two types: those made from wood, and those of sealed tubing metal or composite and/or a combination of these materials construction: referred to as the Stock or Barrel respectively.

Those of a tubular barrel variety have separate "muzzles" fitting in or over one end of the tube, for attaching the rubber bands; whilst others (usually those made of wood), mainly have the bands passing through a horizontal slot in the stock.

A rubber powered gun, besides the barrel, has the following parts:

A Pneumatic gun differs from a rubber model in that it has a thicker spear that goes inside a sealed internal barrel encased in a hollow sealed outer casing that contains the air which is at ambient pressure until it is pumped up by hand to a pressure usually equal to one strong rubber band. The trigger mechanism (which is at the back of the gun) has a handle/grip below it or midway up the gun. Once at the required pressure the spear is forced down the barrel to engage the trigger mechanism and is then loaded and ready. There will usually be a strong line at least twice the length of the gun connecting the spear to the front of the gun. When loaded great caution must be exercised as the speargun is now a dangerous weapon. Without a trigger, rubber bands or air pressure the speargun cannot be loaded and therefore cannot function.

Spears and spearguns have various uses:

All spearguns have a trigger mechanism that holds a spear in place along the barrel.

Traditionally, rear-handle spearguns are popular in Europe and mid-handle guns were used in North America, however as spearfishing has developed as an international sport these distinctions have blurred.

South African speargun manufacturers have improved speargun designs with the use of a rail along the barrel that prevents the spear from flexing under pressure from the rubber bands.

The speargun can have:

Threaded shafts allow for different tips to be used by having them screw on or off. Some tips include a basic short tip with a folding flopper and others use longer tips with a rotating feature, usually with multiple floppers. When larger fish are targeted a break-away tip is recommended (not to be confused with the break-away setup below) as it allows some portion, usually 4-6 inches, of the tip to "break-away" from the main shaft after it penetrates a fish allowing the shaft to "fall out" of the fish but maintain the fish connection by either a small steel cable or high-strength spectra or kevlar line.

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Wikipedia