hankor posted:

Do you guys know what happens when you shoot a gun inside a plane and it pierces the hull (or whatever you call it on airplanes)? Since the pressure is higher on the inside than on the outside all that nice air wants to go through the hole you just created to equalize the pressure, the bigger the pressure difference the more violent this happens. For further information I'd advise you to see Total Recall.

Since we are in a submerged submarine the pressure is much lower than the surrounding water, so there is no chance that our precious air will be sucked out. Worst case scenario is the air getting squeezed out by tons of pressure that violently tears it's way into our sub, but at no point will it be sucked out, in case you were afraid of that.

There might also be a slight risk of a ricocheting bullet hitting somebody or something vital but again, no sucking of any air will occur because of that, unless we hit something that combusts, in that case air will be sucked in to fuel the raging inferno, technically it doesn't get sucked out though so that's not really an issue.

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