Mp9 Not Locking Back.

[Korma]

Hi all,

 

I've bought an ASG/KWA MP9 second hand and I have a little minor issue with the gun not locking back when the magazine has ran out of BBs.

 

Just wondering if anyone has suggestions on what I can do to fix it.

[BigStew]

is it one mag or all mags? what gas are you using? if its one mag, mag follower could be damaged. if it's multiple mags options are it's not cycling fully or the bolt lock open is damage. does it lock when you manually rack the gun?

[Korma]

  On 04/05/2021 at 19:48, BigStew said:

is it one mag or all mags? what gas are you using? if its one mag, mag follower could be damaged. if it's multiple mags options are it's not cycling fully or the bolt lock open is damage. does it lock when you manually rack the gun?

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It appears to be most magazines. I am using green gas but I do have a bottle of red when it gets cold. The bolt sometimes does lock back when I hold up the magazine. I sometimes notice that the bolt doesn't fully close when I do release it. Only a minor gap though. Not sure if this information helps. I can provide any videos if need be.

[BigStew]

  On 04/05/2021 at 20:52, Korma said:

 

It appears to be most magazines. I am using green gas but I do have a bottle of red when it gets cold. The bolt sometimes does lock back when I hold up the magazine. I sometimes notice that the bolt doesn't fully close when I do release it. Only a minor gap though. Not sure if this information helps. I can provide any videos if need be.

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ok so not an issue with mags then. does it lock the bolt if you rack the gun with an empty mag in it? if it doesn't consistently lock i would guess that the bolt lock arm is warn out. if it is locking back consistently the gun is not fully cycling best bet would be to strip the gun clean it and lube it. if that doesn't work something is up with the piston.

[Korma]

  On 05/05/2021 at 14:50, BigStew said:

ok so not an issue with mags then. does it lock the bolt if you rack the gun with an empty mag in it? if it doesn't consistently lock i would guess that the bolt lock arm is warn out. if it is locking back consistently the gun is not fully cycling best bet would be to strip the gun clean it and lube it. if that doesn't work something is up with the piston.

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It sometimes does lock back when you hold the magazine further up into the gun. So I am not sure if that has something to do with it.

[BigStew]

Sounds like the bolt locking mechanism has worn out then. On most airsoft GBBs they are fairly flimsy. I would look on you tube for some disassembly vids. KWA are quiet good for parts but I don't think there any UK stockiest so KWA USA is your best bet you'll be at least be able to get a part number.

[Korma]

I am pretty confident on taking part the MP9 so I will identify the part number and try to track one down. Thanks for your help so far.

[Korma]

  On 06/05/2021 at 09:27, BigStew said:

Sounds like the bolt locking mechanism has worn out then. On most airsoft GBBs they are fairly flimsy. I would look on you tube for some disassembly vids. KWA are quiet good for parts but I don't think there any UK stockiest so KWA USA is your best bet you'll be at least be able to get a part number.

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Are you able to point out what I would need to look for to fully confirm the fault?

[BigStew]

I no longer have a mp9 so nothing to compare it to. As I said a YouTube take down vid is your best bet for comparison.

[Korma]

So I actually manage to fix the issue a few weeks ago, The actual bolt catch wasn't sat under the bolt correctly so I had to reseat it back into position and now works the dream.