The pistol uses a proprietary 4.5mm SPS pistol cartridge that has high penetrating power by replacing the typical bullet with a metal dart. Underwater, conventional bullets are highly ineffective being inaccurate and limited to a very short range with a rapidly decreasing lethality. The “bullet” has been replaced with a long 115mm (4.53 inches) dart weighing 12.8 grams (.452 oz.) made from mild steel that has a slightly flattened tip. The fired projectile is kept stabilized by using a hydrodynamic cavity that is generated by the flattened point of the projectile that results in reduced drag, increased accuracy and lethality. The dart has a longer range and more penetrating power than speargun spears.

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