FX What happens if you shoot an FX with the tank pressure below the regulator pressure?

[Amwolf]

I have no intention of doing that, but my FX dynamic came with all kinds of warnings to not let the tank pressure go below the regulator. My question is what would happen if I did? Would it damage the regulator? Is it dangerous in some fashion?

Sorry if its a dumb question, I am an airgun noobie.

Thank you!!

 

[kwaping]

The pressure differential causes the gun to suck the pellet back into the regulator.

Just kidding, I have no idea.

 

[Ta-Ta Toothie]

You risk getting the valve locked open and possible o-ring damage on the valve assembly.

 

[SilentSquirrel]

You risk getting the valve locked open and possible o-ring damage on the valve assembly.

That's an interesting phenomenon, @Ta-Ta Toothie
Not disputing it.
I'm just not able to wrap my head around it and visualize
How does that occur, please

just my too curious
Edward

 

[Avator]

If it goes too low you run the risk of wiping out baffles for one thing. Another possibly is banging the hammer off the back of the valve.

 

[Ta-Ta Toothie]

That's an interesting phenomenon, @Ta-Ta Toothie
Not disputing it.
I'm just not able to wrap my head around it and visualize
How does that occur, please

just my too curious
Edward

That's just how the dynamic valve is designed. The back of the stem protrudes to the outside of the gun, so when the reg falls below the the set pressure, the valve gets overwhelmed by the hammer over driving it. This is of course for the the dynamic and possibly the drs, I don't believe the impact suffers this.

 

[Ta-Ta Toothie]

Worst case scenario, you can damage the valve, seals ot knock the seat out of place.

 

[Ta-Ta Toothie]

If your lucky and have the valve locked open, you can just push the stem back in to reset it. Have any doubts, buy one and try it out for yourselfs....

 

[EquivalentDelta]

If the internals are anything like the valve in a Crosman, then eventually, you will kill the valve.

Probably not in 1 shot, or even a dozen, but each one does a little damage until it’s fatal.

 

[Ta-Ta Toothie]

Shooting 5 bar below won't cause a problem, just don't go to the extreme. Don't degass the gun by shooting it down even with your hammer backed off. If you're using a HUMA, back out the reg guage to degass the plenum. Turning the screw out won't do jack if your reg is set over 100b.

 

[bchannell]

Depends on how far below reg pressure. Or more to the point is if fired below the lowest practical reg pressure.
If the reg range is, for example, 80-160 bar, and you fired the gun at much below 80 bar, no matter where you have the reg set, then it is possible to blow an o ring or damage the valve.

 

[6gun]

If it goes too low you run the risk of wiping out baffles for one thing. Another possibly is banging the hammer off the back of the valve.

I tend to lean this way. A regulator that has nothing to regulate is less the issue than items tuned for a certain environment id think. I've dipped my impact and dreamline just a couple bar below reg with no ill consequences but im not going to tell anybody is suggested.

 

[shamu]

I have a complete valve kit coming on Monday from Utah to repair my stupid mistake. I degassed my Panthera by dry firing. Not good.

 

[Ta-Ta Toothie]

I have a complete valve kit coming on Monday from Utah to repair my stupid mistake. I degassed my Panthera by dry firing. Not good.

Yup, a while back when I installed my HUMA reg and couldn't degass it with the screw, I asked HUMA how to proceed, they said shoot it down. Completely wrong! My valve got hung open, pushed it back in and the dam thing leaked. One of the o-rings got damaged, valve was ok. Lesson learned. This is a completely different setup from the impact etc. and procedures for those should not be followed on the dynamic platform.

 

[Ta-Ta Toothie]

If you got the AMP reg, just back off the srew once the bottle is removed.

 

[Amwolf]

Worst case scenario, you can damage the valve, seals ot knock the seat out of place.

Ok, so its the airgun equivalent of not dry firing a .22 to avoid damage to the firing pin.

Am I right that the system is designed so that when the hammer strikes the valve pin it encounters a certain amount of resistance from the pressure in the plenum. Take away that pressure and the pin or its seals could be damaged? That actually makes sense. Thank you.

 

[6gun]

Think of the air as part of the valve return spring in your tune. When you lose that spring and you don't have an impact with rubber balls in the valve adjuster.... You're just going to hammer your valve wide open. Hope my crude description helps others imagine the mode of action.

 

[Ads]

I stupidly dry fired my M3 to adjust the first regulator pressure. Even more stupidly I wound it the wrong way and ended turning it all the way up. Now it's leaking pretty quickly from the vent behind the safety switch. Is the valve damaged or the second regulator or both? I'm kind of looking forward to the challenge of fixing this.

 

[Trucker3573]

I believe @Ta-Ta Toothie is spot on. The potential problem(s) are more unique to the dynamic blocked models for exactly the reasons stated. You can very likely damage the valve itself and or the seals.