Donation

All Springer/NP/PCP Air Gun Discussion General > PCP/CO2/HPA Air Gun Gates "The Darkside"

Air usage ????

(1/6) > >>

melloroadman:
Was their some one calculating air usage ? If so condor 480 cc , fill 3100psi , 30 shots, and refill 2000 psi . This one I will pay more attention to next time . 201 converted to 25 caliber . Teathered to a 80 cf tank that is regulated rifle tubes, 380 cc. Start psi was 3100psi , 120 or 130 shots , lost track. End psi 2700 . Marvin

Ribbonstone:
Usually done by keeping track of the volume of air, the pressure used, the number of shots, and the total energy produced by those shots.

Usually worked out as follows:

air volume is cc's X BAR pressure used

The above result is divided by:

total energy of shots (figuring out each shots energy and adding them all up)

So lets say you have a 400cc air tank, starting at 200 bar, you take 40 shots. At the end of 40 shots, the tank has 150 BAR. 
 That gives us the first 1/2 of the equation: we know its 400cc x 50BAR = 20000

The second half requires you to figure the energy for each of the 40 shots taken and add up that energy.   LEts say that adds up to 1280 foot pounds (some shots got up to 38 foot ounds, some were only 29 foot pounds, but in total they all added up to 1280.

So divide 20000 by 1280 and you get 15.625. 

Using this system, the best tuned guns earn a 10 to 12. 

rsterne:
Yep, you need the total FPE for the shot string.... or at the very least the average FPE and number of shots.... to do the calculation.... The results can either be in Barcc/FPE (values from 10 to 20 are common).... or in FPE/CI (where the cu.in. is the volume of air a 1 Bar).... I like the latter system because a bigger number is better.... and values of over 1.00 FPE/CI are reasonably efficient but values under that could use some help.... It depends to a large extent on caliber, however, and big bores tend to be more efficient.... 1.00 FPE/CI equals 16.4 Barcc/CI....

Bob

melloroadman:
n/t

melloroadman:
Thank you but I wanted to know how many cfa was being used . Tank is rated at 80 cf at 3000 psi . So there is 37.5 psi in a cf . I had 3100 psi so I had 116 cfa. to start with . Ended with 2700 psi or 101 cfa . So I used 15 cfa with say 120 shoots or .125 cfa per shot . This I can relate to better . Thanks Marvin

Navigation

[0] Message Index

[#] Next page