View Full Version : LP operation question ...

05-03-2007, 02:19 PM
With all the info on LP operation, one constant seems to be trying to get the striker reset pressure as low as possible ;)

Then using the regulator, raise pressure to get FPM of gun up to the 275/290 range.

*** This is my question .....

Never have I seen a statement that clarifies recock pressure to final pressure in terms of efficiency rating.

In other words ... Does a gun have better efficiency with a large differance in recock to final operating pressure ?
Or, having the recock and final pressure very close ?


Or is this a No Brainer .... in that pressure used greater than recock, is air waisted not pushing out the paintball, and therefor LESS efficient ?

05-03-2007, 03:39 PM
A Spyder converted to LP can still be a gas hog.....
Most people test there markers to lowest recock pressure so they can feel good about there efforts....Since Spyders operate on only one pressure throughout the marker..the only pressure that counts for me is the one that results in both recocking and good velosity for play.
That being said, LP Spyders are more efficent than most HP Spyders. Spyders are not built to the tighest tolerances, so getting great efficency is never going to be possible. The less pressure needed to operate helps, great seals and o rings help, a barrel no longer than 14" helps......
Build it for the least kick and lowest pressure feasible, make sure the o rings are good and the marker is lubed properly, and you will have good efficency.

05-03-2007, 04:26 PM
Thanks for the reply .... But ?

Is there still a degree of pressure differential between recock and operating pressure that is optimal ?

In other words, say your LP spyder with current mods needs 350#'s for 290 fps, What good does it do getting recock pressure low as possible ?

** My thinking is, at the higher operating pressure greater than recock, this equates into a volume of gas going into striker area that is not required and just blows out the vent causing higher gas usage.
And also over drives the striker into the buffer causing higher felt recoil ?

Sorry, I think deep :p

05-03-2007, 05:11 PM
The recock pressure is the same pressure that is the firing charge....
Measuring recock only is a non factor, because the marker runs at one pressure throughout......
You can get the numbers as close or as far apart as possible, but you can only fire the marker with the one pressure.
In my mind, I would guess that the closer the numbers, the better the marker seals and the more of the charge actually goes to propelling the ball thus equalling less pressure total required
recock charge + firing charge = total charge required
There is going to be charge loss in both numbers though, and getting waste to a minimum would be the best idea.....
I imagine firing pressure also can assist in recock, but goes up the feedneck before it can do much good...so the real trick is this:
Adjusting the duration that the cup seal has to be open to both provide the lowest charge necessary to fire and recock at the same time....if the numbers are far apart, maybe the valve stem flows too much to the striker and needs to actually be restricted....that would increase efficency I think....
So, flow needing to be adjusted to both areas will require tunability of both valve opening to the bolt and the striker....you might be in to alot of valve modification before you get the best result but I would be interested in the results!
Good luck

05-03-2007, 05:23 PM
i think when he says final pressure and recock pressure, he means the lowest possible pressure the gun recocks, and the optium fps pressure

05-03-2007, 05:44 PM
i think when he says final pressure and recock pressure, he means the lowest possible pressure the gun recocks, and the optium fps pressure

Yes that is what I am saying. This differance is referred to as the "Differential"


05-03-2007, 05:56 PM
Right. So the smallest differential would be the best.
The problem is the design does not make adjusting the two seperately feasible. So modification to the valve, especially the stem, would be required to tune the two closer........
Since it is so unlikely that one might have say ten different valve stems, (modded for recock pressure tuning) six or seven valve springs, (valve dwell) and several valve bodys (firing charge tuning)... we are just discussing theroy of operation, right?

05-03-2007, 05:57 PM
Theory yes,

But VERY tunable with nothing more than $1.50 valve stems :D

I see it that way because the volume of recock gas is so little of the total charge, subtle volume changes to recock striker would effect little else in the operational cycle.

05-03-2007, 05:59 PM
Well, I think the closer the two, the more efficent the marker will be.