Cardboard in a gas mag

[LUTNIT]

Is there supposed to be cardboard inside a gas mag?

Was taking apart one of my KJW M9 mags to try to fix a leak and found the gas chamber half filled with corrogated cardboard. Is this normal? My original leak problem was caused by paper fibers jammed in the valve keeping it open and wondered where they had come from, now I know.

I bought the gun second hand but the previous owner was fairly new to airsoft so I doubt he took it apart and put the cardboard in there. He told me he had bought it new from a Canadian Retailer (cant remember which one).

Does anyone know why its in there, if its supposed to be in there, if its safe to remove it, and anything else about this that may be important?

[JohnnyDo]

I can't recall why it's there, but I do remember reading that some mags do come with it inside from the manufacture. You can try and do a search on this forum and see what you get. I'm pretty sure I read about it here in a very old thread.

[LUTNIT]

Removed it, reassembled the mag, no change to leak.
Did it all again but lubed up the bottom gasket, stopped leak, shoots fine in the gun without the cardboard (only a couple shots, didnt test a whole mag.)

[GMTII]

1

[LUTNIT]

Found the old thread, wasnt using the right words in my search before (often the simplest thing is the problem...I was searching for "card board" instead of "cardboard")

Its rare to find a KJW mag that has cardboard inside, but some do, what was discussed in the old thread just makes me think it was left inside by the underpaid 12 year old chinese labourer. :-D