View Single Post
Old 01-08-2006, 09:08 PM
bigred76's Avatar
bigred76 bigred76 is offline
Resident *******
Join Date: Dec 2005
Location: San Jose, CA
Posts: 6,228
Default Re: i was thinking about this..

Originally Posted by DRAGON
Nice equations but theory is often offset by reality(one of DRAGON's favorite proverbs). You've left out a bunch of variables such as pressure rating, flow property, flow properties of the valve and regulator, flow properties of the propellant tank, weight of the striker, not only spring weight but spring tension since it is adjustable, shall I go on?
You seem to forget: I used a certain FPS as a reference point. Thus, those factors are included because to get that FPS, the marker has to deal with all those issues.

Originally Posted by DRAGON
This is why you cannot say a certain tank will yield 'X' amount of shots per tank especially with our different LP Spyder setups. Thus another ton of variables from the different modifications and components available on the market. To say that if my Spyder ran at 150psi I'd have better efficiency than if it ran at 300psi is totally incorrect. If you want to dabble in equations, figure out how much total volume of pressure for each shot it takes to push a ball through a barrel at 280fps at 150psi as compared to 300psi not theoretically equating volumes of space within a tank and the marker tubes. It takes less volume to push the ball at 300psi than it does at 150psi. Finding the mean flow per volume per velocity is the key to efficiency -
It seems that you realized here my point of using the velocity reference point. With the same marker, with the same set-up, my little equation will hold true. You WILL get better efficiency by using 150psi than 300psi with the same marker.

Originally Posted by DRAGON
I know this is speaking of another marker but use the new and old Shockers as an example. They both run at extremely low pressures but are total gas hogs from the box. It takes an aftermarker bolt kit to prudently shave that bad efficiency into a more rational state -
READ BEFORE YOU POST! I said that markers with LPRs with different internal volumes will differ with operating pressures. My assumption is that the Shocker has a massive internal compartment for air storage, requiring less PSI becuase it has the same amount of air, even tho it is not as pressurized. I.E.: You can fit 300psi of air in 1", and then put that same exact gas in the same exact quantity at 150psi in a 2" compartment.

Originally Posted by DRAGON
Low pressure does not mean less pressure. Seems that some confuse both because it comes to mind when you say it. They are not synonymous in the least. I'd like to hear Otter's imput on this subject -
You're correct there. Less pressure does not equal less pressure becuase the internal volumes differ as I've already said. I PMed Otter my equation a little while back to see if I could possibly claim the idea for that equation because I didn't know if anyone had done it before. Didn't get a response, so IDK what happened. Hopefully he'll get into this thread.

Originally Posted by DRAGON
See, I didn't YELL or anything of the like -
Go right ahead and yell at me.
SOC (+41, -0) | PBN (+12, -0) | New PBN (+20, -0)

URT... Ultimate Resource Thread!

The [OFFICIAL] Manual Thread!

BigRed Photography

Originally Posted by Muddy Taco
ya my vagina hurts sometimes to
Reply With Quote