Vulcan bullpup- loose, sliding sound when rifle is tilted.

[0akhonor]

I've two of these lovely guns, a .22 and a .25. Had the .22 for over two years, originally tuned by Ernest and resealed by him about 7 months ago.It now has a sliding part noise when the barrel is tilted down. My .25 doesn't make the noise. I've disassembled it all the way down, including the air cylinder, but didn't remove the regulator. The air cylinder seems to be where the sound is coming from- I've taken it apart three times tonight ( draining a lot of air, cause it was filled each subsequent time to see if fixed).
The sound is similar to the FX sliding hammer noise. It shoots well, and I did find the circular plate that holds the firing pin (?) In the cylinder, was not connected the first time I took the cylinder apart. Really thought I had this sussed out, but it's making the same loose piece sliding noise, albeit, it's quieter now than before.
I don't have the owners manual, can't t seem to find a schematic for the air cylinder on the web.
Watched Ernest's vids on the Vulcan forwards and backwards, doesn't look like he's had this problem surface. I plan on continuing to enjoy the rifle, but it's nagging me that it might be getting damaged long term....
Anyone have the schematic on the air cylinder and / or an idea about the mystery noise? I'll YouTube t he sound, see if hearing the noise helps...

 

[0akhonor]

Weird, no?

 

[Siscakidd]

Is the gun cocked? My Wildcat has a floating style hammer that makes the same noise,did you try it with the gun cocked?

 

[Siscakidd]

Sorry did not read the post...just watched the vid and it does sound like my FX 

 

[riazp]

It’s the free floated hammer...

Totally normal, PM me if you would like a picture of the manual.

There should not be anything loose in the cylinder, valve stem, plenum then reg are all under some sort of tension and shouldn’t rattle.

 

[sirk]

well done for finding the loose returns spring retainer. hopefully you did not screw it all the way back in, you must be able to press in the valve stem all the way in with finger tip (tested with no air and the cylinder out) without having it bottoming out on an overcompressed spring. i would doublecheck that.

they removed the brass hammer spring guide(slinghsot anti bounce device) from the .25 because it was limiting power and replaced it with a slightly different shaped hammer and longer spring.
It is very easy to check on the .22, just take the side panel off where the hammer spring is and put your finger in there to see if it stops rattling.

did you lose both user manuals? they have the schematic in them. 

 

[0akhonor]

Great response, thank you. I purchased both rifles used, without manuals unfortunately. I believe the sliding sound is a aluminum cylinder, sliding fore and aft, between the retainer and whatever it bottoms against at the other end within the air cylinder. I can slide it out of the air cylinder, no problem, like it doesn't belong in there? Open ended on both ends, I can't see what it's function would be.
Trying to figure out how the .22 rifle air cylinder should reassemble, I took out my .25 cal air cylinder to disassemble- a known "good" Unfortunately, it doesn't have a air purge screw, so I couldn't tear it apart to compare interiors...

 

[sirk]

thats the plenum, leave it alone there. high pressure forces the regulator against it. if you remove it, the high pressure will move the regulator out from the tube, the breathole must be between the 2 o rings on the reg body.

 

[DeadEyeDill]

I have a .22 vulcan that's also around 2 to 3 years old and it makes the same noise. But it doesn't when cocked. I don't think it's anything my shot aren't affected and more shot could isn't either.. get about 900fps for 55 shots