Just for fun

Just for fun lets discuss this idea.

Feel free to improve, patent, get rich, ect.

Consistant shot to shot velocity is important.
I was wondering this, since we are shooting blowback markers sans my ebolted ones, velocity or consistancy has too many factors.

To stabilize consistancy would it not be wiser to regulate post shot pressure? The pressure propelling the ball?

I imagined installing a threaded pressure relief check valve into the
velocity adjustment hole of the power tube. Making it adjustable for
proper velocity.

The idea is this: Excess pressure at the ball is quickly vented giving better consistancy. A pressure relief valve works by a ball being held against a seat with a given spring pressure. Too much pressure momentarily unseats the ball allowing the pressure to vent out the sides of the device. It will do this until the pressure is insufficient to unseat the ball.

So in short, the power tube pressure is being regulated rather than the input pressure.

Gives us something to talk about

Mark

Sorry, the screw on the left would be the adjustment.

and, Tippmanns never really had underpressure issues.

The overall size could be say as large as 4 paintballs end to end.
I'm not familiar with pump check valves and I hope I explained it
well so we're on the same channel. lol

If others are not familiar with the powertube design, there is a small area in the powertube just ahead of the valve where the released gases meet to propel the ball. The velocity adjustment is basically a blockage in that area. Replacing it with a rapid relief valve was the thought.

Flood the valve with liquid. Shorten the dwell. CO2 boils off at 850psi. Instant consistency. So long as you have the volume of liquid exiting the valve set to a constant (which can be achieved mechanically very easily) you'll hit amazing consistency in velocity.

tallen702 wrote: Flood the valve with liquid. Shorten the dwell. CO2 boils off at 850psi. Instant consistency.

The inherent problem with CO2 is it cools when it expands.

So if it produces 850 PSI and a perfect 280 FPS on the first shot,
it will produce 680 PSI and 240 FPS (guess) on the 15th repeated shot. Burst users may even have cycling issues as internal temperatures head down to minus degrees.

Lets for the moment pretend we are using HPA (air)

The ball is propelled with what I imagine to be a wave of what 650? PSI.
Due to our spring, hammer, reg instability, ect. our FPS is wavering.
maybe 650, 659, 651, 660, etc.

What can control post valve pressure?
Obviously this idea lacks lol
If you could make the pressure in that front bolt to ball area consistant
you could remove effects such as bad regs, poor mainenance and so on. People would line up.

500 PSI in the front bolt every time will shoot the ball at 'x' speed every time I think.

TinMan wrote: tallen702 wrote: Flood the valve with liquid. Shorten the dwell. CO2 boils off at 850psi. Instant consistency. The inherent problem with CO2 is it cools when it expands. So if it produces 850 PSI and a perfect 280 FPS on the first shot,it will produce 680 PSI and 240 FPS (guess) on the 15th repeated shot. Burst users may even have cycling issues as internal temperatures head down to minus degrees.Lets for the moment pretend we are using HPA (air) The ball is propelled with what I imagine to be a wave of what 650? PSI.Due to our spring, hammer, reg instability, ect. our FPS is wavering.maybe 650, 659, 651, 660, etc. What can control post valve pressure?Obviously this idea lacks lolIf you could make the pressure in that front bolt to ball area consistantyou could remove effects such as bad regs, poor mainenance and so on. People would line up. 500 PSI in the front bolt every time will shoot the ball at 'x' speed every time I think.

You don't have the issue of declining pressure with a flooded valve. Each shot is turning pure liquid CO2 at a measured volume into a gas by boiling it as it leaves the valve. Each shot presents exactly 850psi at the given volume. The issue with non-flooded valves is that you get droplets of liquid CO2 in the mix with the gas, these droplets change in volume from shot to shot due to the nature of the gaseous form of CO2 and the set-up of the valve. Thus, if you are siphoning straight liquid into the valve and use a much lower dwell time, you get the full 850 psi every single shot as there is no gas in the valve, only liquid. Constant pressure at a constant volume = same amount of energy shot after shot after shot.

The trick is to get the valve and line going to it cold enough to keep the liquid that is being transfered in it's fully liquid state before it hits the valve. Once you start firing some shot through the marker this is no problem. Most Siphon users will discharge a small bottle through the valve by holding the hammer forward with no paint in the marker to flood the system and keep it cold. They then swap out to a full bottle which will allow liquid to enter the valve from the first shot onward with no issue. Once the system is purged of gas and only liquid is in it, it will stay that way regardless of temperature or how often you shoot due to the nature of a liquified gas in a confined space. It's basic physics my man.

Just so you know. CO2 has a boiling point of -78*C (that's -108.4*F) which means that until the ambient temperature is at or below -108.4*F, it's not going to start producing less pressure.

I'd love to know where you're getting your 50* and 40* numbers by the way, as dry ice can't be formed until it hits -57*C under pressure. You can't even form dry ice in an open environment in our atmosphere, it has to be done in a pressurized vessel and seeing as how the CO2 sublimates readily. You have a chance of freezing some water vapor in the air around it, but you wouldn't stand a chance of "shooting ice pellets" as you were stating.

Chemistry + Physics > Your theories.

As for post valve regulation. What do you think a Tippmann marker does? It uses flow-disruption regulation to change the velocity of the projectile. The power-tube acts as a regulated vessel that controls the flow of air via displacement with the velocity screw.

TinMan wrote:

This is the sad, yet inevitable, result when uninformed opinion meets hard science.

TinMan wrote: I wouldn't exactly call him uninformed.. joking, joking.

You have a sense of humor and handle criticism well.  Those characteristics are good to have here.