What is wrong with my compressed air tank?

[spyderkiller]

I think something is wrong with my compressed air tank. It is a crossfire 68 stubby steel tank. On a full 2500-3000 psi fill I only get around 500-600 shots. What the heck is wrong here? My gun is shooting around 275 when this is happening. It's ok when I'm paying for all day air but when I got to a field where there is no all day air, I get screwed with paying for each fill. Anybody know what's goin on? Thanks

Caleb

[DRAGONSLAYER]

I have a 48 tank and get around 400-500 shots. Since I play mostly hopperball I haven't upgraded. Are you having a problem running out of air during a game? I have access to a breathing air fill station, so I bought a scuba tank and a fill station and fill my own. Check with a local dive shop and maybe you can fill your own.

[X-Plosive]

well thats sounds about right if you're using a boomstick or smart parts AA.

[spyderkiller]

Ok, I have an armson 10 inch barrel. I don't think there are any local dive shops around here and besides I dont really want to take the time to become a certified fill technician or whatever the heck you have to do to be able to fill your own.

[PyRo]

600 shots sounds about right to me. Your compressed air tank in no way effects efficiancy, unless it is leaking. Are you sure that you don't have a broken, or knicked o-ring. Any leaks in the gun will also effect this. How is your paint-barrel match? Too loose or too tight will cause you to loose efficancy, and can also cause eratic velocity. How much porting is on that barrel? Porting will also decrease your efficiancy.

[ZeroXtreme]

Actually, the other factors like bore size and paint matching, porting, length, etc. really do affect performance like accuracy, distance, noise, etc. However, if you are using a Mag, they do not affect the amount of air expelled from the chamber of a mag. Of course CO2 is affected by temperature, the colder it is the more gas is used up.

One of the beauties of the Mag is how the whole valve/regulator system works. The chamber is always filled with as much gas that it can fit, when the gun is not being fired. Once the trigger is pulled, the front part of the sear releases the bolt and the rear part of the sear depresses the on/off shaft that blocks of the chamber from being filled with air. Once the trigger is released the on/off shaft pushes the rear part of the sear down locking the front part on the bolt again, and unblocking the air passage to the chamber.

So there is no excess gas being expeled since a fixed amount of gas is all that comes out because the air source is blocked off.

[TheTramp]

The most shots I've gotten was around 700 or so. That was with a full (it was a 4500 system) 3000psi fill. 68ci just isn't that big and the Mag uses a fair amount of air. Not the worst but also not the best.

[raider_o1]

ZeroExtreem, the amount of air in the chamber effects the velocity of the paint. This is changed by increasing the pressure via the regulator adjustment screw on the back. At velocities over 300 fps this can effect accuracy on most paint as well.

[DRAGONSLAYER]

You don't have to be certified to fill your own. Just giving you my opinion and how I overcame my problem.

[PyRo]

Originally posted by ZeroXtreme
Actually, the other factors like bore size and paint matching, porting, length, etc. really do affect performance like accuracy, distance, noise, etc. However, if you are using a Mag, they do not affect the amount of air expelled from the chamber of a mag. Of course CO2 is affected by temperature, the colder it is the more gas is used up.

So there is no excess gas being expeled since a fixed amount of gas is all that comes out because the air source is blocked off.

WRONG!!!!
Bore size and paint matching, porting, length, etc Do effect gas efficiancy. On no gun do these factors effect the amount of air expelled from the chamber, this is not unique to the mag. Also, if you have a bad paint-barrel, lots of porting, or execesivley long barrel, it takes more air to do the same job, meaning you will have to turn your veleocity up.
Lets say you have a Lapaco with a good paint-barrel match(11.5in, very little porting).
Now, lets say you have an Smart Parts All American with a bad paint-barrel match (18in, lots of porting).
You crono in with the SP at 300fps. But, you decide to try out your new lapaco barrel. You put it in, without changing the velocity, go to crono again, and your velocity is now 350.
Now, when you turn down your velocity, you use less air per shot correct? So, the SP is using up more air then the lapaco, to get the same results.

[raider_o1]

Originally posted by PyRo


On no gun do these factors effect the amount of air expelled from the chamber, this is not unique to the mag.
-snip-
So, the SP is using up more air then the lapaco, to get the same results.

So tell me what are you saying? They do or do not? For the record, they do... less air is a result of less pressure which gets less velocity and all this is effected by pressure reg on back of mag. And I do not care if the guy is a moderator, the mag is not low pressure. (different thread)

As for the Nitrogen question: $ for $ CO2 will give you more shots. The major reasons for switching to N2 is 1) less velocity fluctuations and 2) no chance of freeze up due to liquid gasses (mags only). As for shots per tank; your gun and bottle are working fine. Field owners, if they are smart, get insurance against liability claims. Those that disregard the field air only policy will be out of contract shortly. Using a 3000# scuba tank is a great way to fill your tank in the backyard w/o any license, but good luck finding a dive shop to fill it, if you have--good for you. A 90 in3 seams like it would have a decent shot count while still being light and small. (my next tank)

[ZeroXtreme]

Pyro & raider,

I'm sorry for forgetting to mention the effect of turning the velocity screw on the back of the regulator has on the amount of air that is fed into the chamber.

You are both correct about this affecting the amount of air, the more the velocity screw is turned in, the more gas is crammed into the chamber beacuse of the higher pressure, and the higher the velocity will be. This will result in less shots per tank. You are also correct on the other factors affecting the efficiency, but my main point is that once the velocity screw is adjusted to the proper specifications of the barrel and paint, etc., then only a fixed amount of air in the chamber is expelled from the gun, no more and no less.

Other guns do not seal of the chamber from the rest of the air source like the Mag does, that's why the amount of gas they expell are not as exact as the Mag. This was my main point.