bulk question!

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killercrow
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Joined: Thu Oct 13, 2005 5:20 pm
Location: Spruce Grove AB

bulk question!

#1 Post by killercrow »

hey guys, heres a question for those of you who use bulk co2. as you use the co2, does it gradually lose pressure? it seems mine is, after maybe 100 shots fired on a 20 0z. tank. i shot over a chrony today and im only getting 580 fps. a while back i was getting 630 fps with a powerlet, and ive done additional mods to increase power since then. does this make sense? maybe i should get myself a pressure gauge...
well, lmk if youze guys know something i dont :lol:
thanx.
al.
killercrow
Posts: 2374
Joined: Thu Oct 13, 2005 5:20 pm
Location: Spruce Grove AB

#2 Post by killercrow »

oh btw, the 630 fps was shot outside at around 40*F, and today the 580 fps was shot inside my house at around 75*F.
killercrow
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Joined: Thu Oct 13, 2005 5:20 pm
Location: Spruce Grove AB

#3 Post by killercrow »

so whats the deal!! :roll: :lol: am i just asking a stupid question or what? :?
MC 84
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#4 Post by MC 84 »

the thing with co2 is it not regulated like hpa, so the output psi could be all over the place. you should try HPA, i just bough a tank off ebay that has an adjustable regulator and i can adjust the output psi all the way up to 1500 psi. thats gonna send those pellets flying
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sniper
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#5 Post by sniper »

Sounds like a normal incident.
I did one experiment with 2250 mod. Using powerlet it was doing 740-750 then I installed co2 bulk 9oz was doing 700-720, 16oz = 720-740. The co2 itself gives constant pressure about 900 psi and constantly equilizing the pressure at 70F but sometime powerlet compress co2 with higher pressure. No need for pressure gauge since only going to tell you the pressure in the container not the amount , unlike PCP. Another experiment I did on the bulk mod QB, fill in with co2 and it does very well at 745 and then add pressure using HPA pump upto 1300 psi and it does 839 consistently.
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ustilago
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#6 Post by ustilago »

I had something similar happening with my 2240. I did a few valve mods (ground out the edge of the exhaust port and increased the volume by cutting off half of the threads, I also swapped in a lighter valve spring) and I found that the first two shots were low and after that the velocity would start to climb. I had the springs balanced so that at lower pressure the valve would not snap shut as quickly resulting in a larger volume of CO2 being released with each successive shot.

Theoretically, I could throw a regulator on it (whenever my 12g carts show up) and run at a lower pressure.
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