When you shoot a gun in Space, shoot a gun in underwater?

A while ago, I was watching one of my favorite Marvel Movie “Avengers: Infinity War”. There was one scene there when Stark fought Thanos with his flagship weapon, releasing large bullets from the iron suit He was wearing. So powerful. Although the battle was on another planet. Then I became curious, would the weapons commonly used on Earth -like gun and bullet- can shoot in other planet or space too? The answer is Yes. You can still fire the bullet even at the near vacuum conditions. Because current bullet contains its own oxidizer, an additional chemical that can help to trigger the burning (just like oxygen). However, it has different lethal ability compared with a bullet fired on Earth.

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When you fired a bullet in different pressure situations, air molecules will greatly affect its speed resulting in the different lethal ability of the bullet. Bullet fired on Earth -open air- will reduce its speed because air molecules such as oxygen, nitrogen, and water vapor inhibit the bullet movements by making friction forces. So eventually the bullet will lose its strength and falling to the ground after several meters. Whereas in near-vacuum Space, there are no inhibiting molecules, the released bullet can travel without decreasing its speed. Once shot, the bullet will keep going, for forever.

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Thus, air molecules are very influential on the lethal ability of the bullet, we just do not care about it because it is invisible. Whereas it is very important towards bullet speed. In the opposite situations such as underwater, which have different molecular densities, the effect on the bullet is inverse than in space. The close distance between water molecules makes the bullet difficult to move, the water friction will greatly hold the bullet movements from traveling far. To penetrate the water molecules, special design bullet is needed. It called by an underwater bullet. The underwater bullet can pass through water molecules by supercavitating principles, by creating a bubble around the bullet that will reduce the water friction.

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They are created with specific functions to travel underwater with high speed. Unfortunately, they cannot maintain their quality when they used outside the water. It is not effective when used in case of water-to-air or air-to-water, the standard underwater bullet won’t work well in the open air.


To deal with this problem, Duretek company developed an advanced underwater bullet that can work best in both conditions underwater and open-air situations. It is called by GP bullet. GP bullet designed by used high-density material in the front and low-density material in the rear, resulting GP bullet can reduce the water drag and air resistance. GP bullet also very practical because it can apply to the various warhead and do not need to require a special firearm to use it. Interesting with GP bullet? Please contact sungjin@duretek.com