SpudFiles

Ok guys here is my new piston idea. I call it a Boost Piston. Thw whole idea is to Boost the psi in the chamber, Get ALL the air in your chamber out of the gun quicker and, keeping it consistant.

How it Works:

There is a air tight piston in the chamber of the pneumatic cannon. There will be 2 guages, and 2 scharder valves on either side of the chamber. In fornt of those Shcarder valves, that pop out into the chamber there is a disc that keeps the pison from hitting a scharder valve or gauge.

First you fill the front of the chamber to a normal PSI as you would do to a cannon of that chamber size. Lets say 80psi. Then after your done filling the front of the chamber(in front of the piston) then you are going to fill the back of the cannon(behind the piston) as much as your compressor can get it. So now you have lets say 80psi in front and 20psi in back.

When you fire the cannon a lot of the air is relaesed quickly, and hard into the barrel, but those last 20-25 psi's are being wasted in the chamber, and arn't giving a full effect to the porjectile. But with the BOOST piston once you get a lot of those psi's out the last 20 psi is being forced out of the chamber by the piston equilizing the pressure in front and back.

This poston should BOOST your projectile range, and speed. It will keep your chamber at a higher PSI and Squeeze out all the last psi's avialable in the chamber.

To get a even BETTER result from this piston, you would need to keep your compressor hooked up to the valve behind the piston, pushing the bolt earlier, faster, and harder than when not being hooked up to the compressor.






Orange circles: Pressure guages

Orange rectangles: Scharder Valves

Green: Piston

Black: Piston stoppers

Dark blue: High pressure Air, in chamber

Light blue: No pressure, in chamber

What do you guys think of my BOOST Piston Idea?

It's an idea that would work but the same effect on performance can be achieved by simply using a larger chamber, I really doubt it's worth the trouble.

90% of the air is wasted anyway, once the projectile's out there is no point.

It's not like air is gold or anything.

As for your idea, 8). Go ahead and try it.

Rudesill Ballistics wrote:90% of the air is wasted anyway, once the projectile's out there is no point.

...but keeping the air at higher pressure while the projectile is still in the barrel will increase performance - though again, you can do this by simply increasing the size of your chamber.

That could come in handy for small guns, even handhelds! Nice idea, Cannon Creator!

OMG i finnaly get it

yeah thats a good idea for smaller guns. like pistols and stuff like that

wannabie wrote:yeah thats a good idea for smaller guns. like pistols and stuff like that

In that case, a much simpler solution would be to ensure you have an airtight piston and put a stiff spring between the piston and the chamber.

hmmm sounds good lol

Hi,

Hmmm it could make a nice recoil damper, if you have that 180 degrees bend that you will typically have on a piston valve gun. Or, rather, with a good projectile to booster piston weight proportion, it will delay the recoil until after the projectile has left the barrel.

As for efficiency, I guess the booster piston will not start re-compressing the air in front of it until rather late, and it won´t have much effect.

Regards
Soren

DO NOT USE THIS IDEA! UNDER ANY CIRCUMSTANCES!

I saw an idea like this a year back now, and I quickly spotted one HUGE flaw.

You are effectively firing the piston into the cannon.

The piston in the chamber is going to be accelerated to incredible speed during the firing - think how fast your ammo goes, take a bit off it, and then you'll realise that you're playing with fire.
It will then fly along the chamber, and if you get really unlucky, it'll then punch it's way out the other end. Even if it doesn't break free first time, the repeated impacts will eventually tear something loose, and cause major injury.

Sorry to shoot down the idea, but if you think how a potato can go through 3/4" plywood from your cannon, then although you won't get quite the same energies, the pounding this will generate time after time will either smash the piston apart, or the cannon. Not good.

DON'T EVEN THINK ABOUT TRYING IT!

Sorry about the huge red letters, but you really did need to read this.

By looking at your design, wouldn't the pressure on either side of the piston end up being equal? If you charged the front to 80 psi, and then let the compressor pump the back to as high as it can go, wouldn't it equalize before it wouldn't be able to fill it anymore?

Either way, it would still work the same. But I do have to agree with the post of above me about the possibility of this thing blowing itself apart. The only thing I can think of would be to have some type of progressive spring or shock absorber that could absorb the impact of the piston. A simple bumper wouldn't be enough either. But I do think it could be done, with the right type of spring, and if you made everything out of metal, NOT pvc. I wouldn't trust pvc to that kind of impact, with or without a spring absorber.