Guns Underwater: Do They Work? ~ VIDEOS

Just for fun: can you shoot underwater?
This VCDL guest article was written by a gun-rights activist from Texas, Jay Chambers at

Virginia – -( I love science, so I was interested from the point of view of physics. Glock has a modification to their guns that allows for them to shoot more easily underwater. There is a video showing someone hunting lionfish in Florida with such a Glock. Of course, the gun must be very, very close to the fish to work. The real problem with shooting underwater is that water, unlike air, does not compress as an object moves through it.

Guns Underwater: Does it Work?

Maybe they’re rare, but defensive situations in the water are possible. So, if you carry a gun, it’s worth discovering if your firearm would work underwater. That way you know whether or not it should even be part of your gameplan.

Also, it’s just fun to know more about guns.

So, let’s find out if your gun would work if you needed or wanted to use it underwater.

Will Your Gun Work Underwater? In short, your gun will function underwater. But, firearms are not very efficient underwater. So, your gun may not work for what you need it to accomplish.

Water causes issues with the ammunition, the action, and the projectile ballistics.

The Ammunition

The issues start with water getting into the ammunition. Modern ammunition is somewhat watertight. It resists rain and external moisture very well. Even being submerged isn’t enough to immediately foul your ammunition. A minute or two underwater usually won’t cause the ammunition itself to fail.

However, if it sits underwater for hours or longer, it’s likely that water will get into the casing and render the powder too wet to ignite.

The chances that you’ll need to use your gun after being underwater for hours are slim. So, it’s most likely that your gun will go bang when you press the trigger underwater.

There’s a notable exception here: rimfire ammunition. Rimfire ammunition is known to be especially susceptible to water fouling. If you’re using a .22 or some other rimfire cartridge, it’s much more likely that your gun won’t work underwater at all. It may be best to leave your firearm out of your underwater defense plan if you use a rimfire model.

One last point: there’s no way to verify if your ammunition has been water fouled or not. Once your gun is out of the water, you should replace the ammunition that was submerged with the gun. It’s the only way to ensure the reliability of your firearm once it’s dry.

But no matter what type of gun you use, keep your ammunition dry if you can, and plan for a complete firearm failure if your gun gets submerged.

The Action

As you know, guns are designed to work in standard atmospheric conditions. So, being submerged in water causes trouble with the action of most semi-automatic handguns and rifles.

Often, the expended casing doesn’t get ejected correctly and causes a stovepipe or failure to eject. Or, the water slows the action down too much for it to cycle completely. This causes a failure to go into battery or a failure to feed.

Either way, being submerged in water essentially turns your semi-automatic firearm into a single shot.

But revolvers don’t suffer from this issue. And, there’s evidence that an AK-47 is able to fire repeatedly without malfunctioning.

But, the chances that a semi-automatic firearm will malfunction underwater are very high. Unless you’ve got a revolver, it’s smart to plan for only one shot before performing a malfunction clearance.

The good news is that most standard malfunction clearance manipulations work just fine underwater. So, you could get another shot, if you clear the jam.

The Ballistics

This is where things get interesting. The effective range of every gun drops dramatically when it’s fired. So dramatically that you won’t be able to count on anything beyond about five or six feet.

Once you get your gun underwater, the barrel almost immediately fills up with water. All that water has to be pushed out of the barrel by the bullet. Depending on the length of the barrel, the weight of all this water might be several times heavier than the bullet itself. Pushing this water significantly reduces the muzzle velocity.

Then, cutting through water quickly reduces the bullet velocity. The projectile becomes non-lethal very quickly.

Interestingly, using a non-rifled barrel actually works better underwater. Rifling destabilizes the bullet when it moves through water because the viscosity and inertia of water is higher. That’s why guns designed to work underwater have smooth bore barrels and often fire flechettes instead of standard bullets.

But, since you’re most likely not carrying an underwater pistol, you’ll get poor ballistic performance when you fire your gun underwater.

Also, even if your bullet exits the water shortly after it leaves the barrel, it will still be severely hobbled in terms of ballistic performance. The water already did it’s damage to the bullet velocity and stability.

So, it’s wise to plan on taking a contact shot if you want a good effect when you shoot your gun underwater.

Coming up for Air

Unless you live or work around water, the likelihood of needing your gun in an underwater shooting context is extremely low. But, if there’s some reason that it could happen to you, brush up on a few skills:

  1. Malfunction clearance.
  2. Grappling skills.

These skill sets will help you get more than one round from your gun, and protect your gun while you maneuver for that contact shot.

So, to answer the question we started with: yes, your gun will work underwater, but in a very limited capacity. It will require more than standard shooting fundamentals to effectively deploy your gun while in the water.

Virginia Citizens Defense LeagueAbout Virginia Citizens Defense League, Inc. (VCDL):

Virginia Citizens Defense League, Inc. (VCDL). VCDL is an all-volunteer, non-partisan grassroots organization dedicated to defending the human rights of all Virginians. The Right to Keep and Bear Arms is a fundamental human right.

For more information, visit:

  • 9 thoughts on “Guns Underwater: Do They Work? ~ VIDEOS

    1. Guns do work underwater if they are using supercavitation munitions. Pistols do not get much gain but rifles do. 5.56 is 16 meters, 7.62×51 is 25 meters and .50 bmg is 50+ meters water to water.

      The trick to cycling the action is piston driven and cutting holes in the buffer tube. Then you can go full auto underwater.

    2. The unorthodox exception to this would be the SMG speargun.
      I had one, but it got lifted in a burglary. Dang $$$. Idiot me didn’t have the serial number recorded. Anyhow, what most of the people misstate in the adds trying to sell these is that they used .22 RAM-SET blanks, not just .22 blanks. The ram-sets must be reasonably waterproof for these to be be at all marketable. Never shot mine, but from what I read at the time they had an effective range of up to 20′ or so with the high power cartridges.

      Wonder what the ATF makes of these things.

    3. Glock doesn’t have any modification to make it shoot better under water. It has a spring cup modification to prevent a hydraulic lock of the striker after trigger pull. If you have air in the barrel, under water, the bullet pushes the bubble out, and flies through the bubble (9mm ball) and goes about 24 inches. If you have water in the barrel, the bullet will travel about 2.5″ and lodge in the barrel, bulging the barrel, rendering the gun useless. Btdt, 1992, John Shaws pool at M.I.S.S. With Glock rep Grounds present. 4 Glock 17’s, 4 shots, 4 bulged barrels, 4 ruined guns. Glock covered them under warranty. I won’t say which agency we all worked for at the time.

    4. It’s actually important to clear out the air in the barrel. Not good for the bullet to race down an air filled barrel and slam into water.

    5. This was a very interesting article. I just thought the use of a gun underwater was not something a normal person would do.

    6. Crazy, I didnt think it would work without blowing up the chamber. I have used water to clear stove pipes though in a revolver.

    Leave a Comment 9 Comments

    Your email address will not be published. Required fields are marked *