The air pressure that the ball sees?

[FallNAngel]

I'm having a small debate with someone about LP vs HP (...again...). Anyway, he's saying that the pressure the ball sees in LP guns is less than the pressure the ball sees in an HP gun. Any idea which is true?

[SlartyBartFast]

Go look at the graphs in the data thread. Ball sees the same pressure in all guns.

[hitech]

Yes, you will find the graphs of the pressure behind the paintball in the data thread.

Also, here is what Tom had to say about the pressures in a 'mag:

I will clear this up. Firstly the bolt is being pushed forward with the 375 psi in the chamber. The bolt is being pushed with about 18 lbs of force but this will change in the upcoming versions. The force behind the bolt really does not matter it is bolt speed that counts.

The air blast behind the ball after the bolt pushes it in the breach is about 60 lbs for the Mag and the Impulse. According to many this is the reason you buy a low pressure marker. I am sure the Impulse guy will find some way to argue with you on all of this I would just let it go.

AGD

[FallNAngel]

Well, that 1/2 answers my question. I have looked in the data thread and looked at the pics (even before I posted). The question I have is, say the Angel shows the ball ~90psi (just a guess off the top of my head) with an operating pressure of 450. Will it show the ball more, less or the same pressure if the Angel is made LP and brought down to say... 200psi?

[hitech]

Will it show the ball more, less or the same pressure if the Angel is made LP and brought down to say... 200psi?

It depends. It will probably change very little.

[athomas]

The gun needs a certain amount of pressure to start the ball moving. With most setups, depending on the airflow, this works out to be about 60psi. Some are more. Some are less. Once the ball is in motion, the ability of the gun to maintain the airflow comes into play. If the air source is low pressure, then all the air paths leading to the ball have to be less restricted. If the air source is high pressure, then the restrictions in the air paths are more forgiving and the higher pressure can compensate for these restrictions to maintain airflow. The higher the pressure you can deliver to a ball before it starts to move, the more efficient your shot will be. That means you are able to deliver the air faster and more efficiently so the ball doesn't start to move before the air pressure builds up as far.

The bottom line is that almost all guns require approximately the same behind the ball pressure, because all balls require the same energy to accelerate to 300fps. That, and the airflow paths aren't perfect.

[Eskimo Paint Slinger]

This might help you out with your argument:

http://www.thingpaintball.ca/lowPressure.shtml

[athomas]

Excellent article.

[nerobro]

IIRC an impulse was tested. they run under 250psi. take a look ;-)