SpudFiles

cannon monkey wrote:this is just me being stupid but could i sit on my chamber and fire under water do you guys think it would push me or just end up me with broken bone or badly hurt

if you guys think it will work i bring under water camera

Only if you are a girl...




I mean, besides the fact that your family jewels 'll get rammed off, you will get pushed...

The difference between a water rocket and a spudgun under water is that the rocket provides a constant force over time, and the spudgun is just BLAM.
First fire a barrel full of water (carefully, low pressure) and then see for yourself how much it will push you. A completely submerged spudgun will push even harder.

EDIT:
Maybe if you use a small constant air thrust, you could. A big air tank and a blowgun perhaps?

Look, todo it you need a way of either firing and taking the recoil or have the gun do it on its own.

Be inline with the gun and have it rest firmly on your shoulder, avoding the colar bone, you should be lieing, use a snorkel, when it fires just be ready for the gun to push you back.

Or

Hold the gun well under you, when you fire release your grip and watch her fly, make sure the area behind you is clear. And that there is nothign on the gun that can take of your fingers.


Best bet is something infront of the barrel to stop water from coming in.

well thats interesting to no i do hav a underwater camber so i might try this but i will need to work out some sort of fill meconism

Fill with bike pump, above water, then put it underwater?

Please use your common sense and fire it remotely.

I think that the result will convince you to never try it while holding it under water.

This idea seems very dangerous and could probably kill you.

I strongly advise you not to hold any pneumatic spudgun underwater while firing.

Brian the brain wrote:Please use your common sense and fire it remotely.

I think that the result will convince you to never try it while holding it under water.

This idea seems very dangerous and could probably kill you.

I strongly advise you not to hold any pneumatic spudgun underwater while firing.

Well actually btb as long as you are bracing it against an object it is quite okay. I made a simple coaxial and shot it underwater. While i think it was the smallness of the gun (1/2 inch chamber) If a cannon is braced it should be able to take the force. I wouldnt use pvc though.

Pneumatic? Look at it this way: You already have it at a 'high' pressure. The fact that it will take a much longer time to expand through the barrel and at the same time be decreasing in pressure, while under water, tells me that the 'impact' you seem to be anticipating is going to be far less sudden than you think. The water will help to keep the recoil from being so violent as it would be in air. And, unless you use a 'spear' as a projectile that completely fills the barrel to displace any water, you won't get much out of it but a rush of bubbles.

kenbo0422 wrote:Pneumatic? Look at it this way: You already have it at a 'high' pressure. The fact that it will take a much longer time to expand through the barrel and at the same time be decreasing in pressure, while under water, tells me that the 'impact' you seem to be anticipating is going to be far less sudden than you think. The water will help to keep the recoil from being so violent as it would be in air. And, unless you use a 'spear' as a projectile that completely fills the barrel to displace any water, you won't get much out of it but a rush of bubbles.

100 psi buy no means is high pressure. Its not pressure that matters so much as volume of air and water displacement. The golden law that everyone loves, for every action there is an opposite and equal reaction.

i was just asking if it would be ok if it got wet

That's normal on this forum. A simple question can end up in an endless discussion.

As long as your cannon gets "wet" there shouldn't be a problem. Just check that there is no water in it before you fire it.

bradisfun wrote:i was just asking if it would be ok if it got wet

Yes. A cannon can get wet and may safely be fired again, even while wet.

For the others:
Firing while underwater is dangerous. On top of that barrels full of water have been known to snap a fitting and blow the cannon.

Obviously you've never watched explosive decompression up close under water. If it were a combustion, I might agree, but not with this.