Venting out the back??

[PRPB]

ok I know it suppose to vent out when it over pressuizes when using co2. Now today I gave my dad a mag for christmas and we when out side to test it. It worked fine for the first 200 or so shots. Then it started venting out the back. Now the thing is I'm using a HP tank. So why would it start venting out the back?

What I have:
lvl 7 68 automag valve
Crossfire 88/4500
microline (I know I need to change that)
velocity was at 280.

[purplemag]

I am guesing the Crossfire is a preset tank about 850 psi? This could be slightly higher than the input of the CO2 was and thus if you were right on the edge of venting before it would start now. But CO2 and HPA will cause the mag to vent at the same pressure, correct me if I am wrong guys, but like 300 psi internal pressure to the mag valve? Just turn down the velocity, and if LVL 10 may have to change springs.

[Dayspring]

The gun will vent after 300FPS. The internal regulated pressure is ~450.

[PRPB]

Originally posted by purplemag
I am guesing the Crossfire is a preset tank about 850 psi? This could be slightly higher than the input of the CO2 was and thus if you were right on the edge of venting before it would start now. But CO2 and HPA will cause the mag to vent at the same pressure, correct me if I am wrong guys, but like 300 psi internal pressure to the mag valve? Just turn down the velocity, and if LVL 10 may have to change springs.

The input pressure is 800psi and I did turn the velocity down and it still vented out the back. Then I degassed it tehn gas it back up and it work fine then it started again.

The gun will vent after 300FPS. The internal regulated pressure is ~450.

I don't know, my minimag has never vented out the back. And I have had the velocity spike to 680fps with co2. And with my HP tank I have had it at 460fps and it never vented once.

[purplemag]

When you are out of HPA have someone check or check yourself the internals of the HPA tank reg. A reg seat or something of that sort might have gone bad causing input pressure to rise after shooting. I know my max flo had that problem and the pressure would rise until the gun vented.

[PRPB]

No my tank is fine. Nothing wrong with the output pressure.

[welt]

same problem

ticked me off. I'm playing woods ball with a few friends and i'll go a little while with out shooting 'cause i'm looking for them or trying to sneak up on them then all of a sudden it starts venting, alot, and it won't stop 'till I shoot, sometimes I have to shoot it a few times to stop it. You talk about a freakin' gas hog, might as well have a tank leak, same difference. I might have to look into a differen't gun.

[Dayspring]

Don't go and get huffy and get another gun. Look into replacing the part (reg piston).

[welt]

Thanks.

I'm not a patient person. If I take care of the gun and oil it I expect it to work. I don't want to waste a Saturday 'cause my gun isn't working. That's why i bought a Mag in the first place so I wouldn't have that problem. I guess i'll have to keep both Mags so I have a backup. Thanks for the info i'll check it out.

[Aegis]

Deep breath, everyone. I have faced this with several used mags, actually almost every used mag. In every case the cure has been one of two things:

A rebuild kit install to renew all the seals:

A new reg piston with the higher pop-off for level 10 installs that just won't stop venting at normal velocity.

If you have not put a new set of O-rings in, you might be chasing your tail trying to figure out what is wrong.

[welt]

Rebuild kit

That's just all the rings right? Thanks alot, I was getting frustrated. Now once I do that how many paintballs can I go through before I have to do this again? Estimate?

[slushee]

considering I play cdn tournies ... um, I replace my rubber (ahah) once a year but I shoot like 5 cases every other w/e

the kit should last quite a long time as long as you clean and oil the marker after play

[bgredjeep]

[purplemag]

Yes that o-ring is supposed to have the crack in it!