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Old 07-03-2013, 09:59 AM   #14
gmw
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Quote:
Originally Posted by ApK View Post
From one of the video comments:
"Hydrostatic pressure doesn't quite work that way because it is pushing equally on all sides of the firing pin. A parallel example is that it does not take 4x the force to swim at 100ft as it does right under the surface even though pressure is 4x as great. What matters with drag is the density of the fluid, which fortunately for water does not significantly change with depth."

I'm confident he is correct.
When I dive, my neoprene wet suit compress and gets a bit stiffer, and the air cavities in my body get squeezed, but my muscles and joints continue to work just fine. The valves and switches on my equipment are no harder to operate at depth than at the surface.

ApK
Thanks. That all makes sense. If we assume that there are no air pockets inside the mechanism of the gun that might collapse at depth (and so possibly distort some element before firing), then I can accept that the firing mechanics of the gun may still work.

One of the things mentioned in some of the articles about firing under water is that most bullets are sufficiently water proof that water doesn't enter the case. However I doubt if the case is water proof to hundreds of feet, I wonder if it will just let water in and so even out the pressure, or whether it might collapse at some point with possibly unpredictable results.
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