Fine, give me a minute to transfer the stuff from the PM I was writing to you....
Quote:
HPA Tanks:
Shots Per Size Formulas
PSI (tank 1) X CU (tank 2) / shots (per full tank) = PSI per shot
T1 * T2
S
E.G. 141,000PSI divided by 750 shots per full tank equals 188PSI per shot
(141000/750=188)
PSI (tank 1) X CU (tank 2) / PSI per shot = shots (per full tank)
T1 * T2
P
E.G. 68ci times 45000PSI divided by 260PSI equals 1176.92307692 shots
(68*4500/260≈1177)
The first marker is my Spyder Imagine. The second marker is Bomberpilot's ProMaster.

The first marker is my Spyder Imagine. The second marker is Bomberpilot's ProMaster.
These equations work on these markers because the internal volume is 1 cubic inch. On other markers, like Intimidators, the internal volume is slightly different. To find the exact size that the internal volume of their V/A and LPR is, I would need to fill one with water and measure every last drop of it. AKA, I'm still working on it.
TL;DR: Lower pressure does equal better efficiency SO LONG AS you are talking about an LP
running pressure, which I classify as a pressure that your marker shoots 275fps at...
Oh, and yes. I did come up with those by myself. I got kinda bored one day LOL! [/ninja edit spree]