Kwa MP9 sometimes won't shoot a bb

Discussion in 'Gas Powered Guns' started by not_an_noob, Jun 7, 2015.

  1. not_an_noob

    not_an_noob Member

    98
    0
    San Francisco
    So I just bought a used kwa kmp9 and it will only shoot a bb every 10 cycles. When I pull the trigger, it makes a quiet pop and the bolt cycles, but not all the way. It also doesn't shoot a bb when it does this. Occasionally, I will get the gun to make that loud crack when I pull the trigger and it does fire a bb, but that is very rare. After continuing to troubleshoot for a couple hours, I found that the cylinder was cracked. Is this the cause of the problem, or is it something else? The seal under the cylinder was also clear. Isn't it supposed to be orange? Is it a knock off gun?

    I'll also mention that the gun is about 3 years old, and the previous owner lived in chilly Washington. They said it wasn't used much though. I'd really like to know before I purchase parts and pay the hefty shipping charge. Thanks!
     
  2. Pirate223

    Pirate223 New Member

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    0
    I can help you more if you make a trouble shooting video.

    Your problem sounds like this spring: http://store.kwausa.com/partskmp9ns2seriesdisconnectorspring.aspx
    Sometimes if this spring is too tight, it will cause the bolt to not return all the way back to the breech. Try stretching it out with a screw driver slowly and carefully. If that doesn't work, then buy a new one.
    This doesn't actually show until the gun is broken in a bit, so if the owner didn't use it much then the gun is probably barely broken in.

    The cracked cylinder is a separate issue. You'll want to replace it, but it's not as bad a fix. Also, buy an extra set or two of nozzle return springs while you're at it. They are notorious for breaking.

    I'm not sure about the seal being clear. If it bothers you I'm sure you can get a replacement.
     

  3. Rushin

    Rushin Well-Known Member

    3,920
    32
    Kalamazoo
    It's also the loading nozzle. Mine got chipped a while back and that caused a whole host of problems. Every KWA gun I have owned did this.
     
  4. MP5User

    MP5User Active Member

    2,288
    12
    Westfield
    Loading nozzle is not a separate issue, it is 9/10 times going to be the cause of the issue if it's cracked or broken. You'll want to buy a new loading nozzle for sure. Assuming the gas can you're using is not close to empty, this should solve your issue.

    You can look up a parts diagram on the KWA Proshop, and if they don't have parts listed, you can give them a call as they tend to have a lot more in inventory than is listed online.
     
  5. not_an_noob

    not_an_noob Member

    98
    0
    San Francisco
    So is a loading nozzle the same thing as a cylinder? They look pretty much the same from pictures but I'd just like to clarify
     
  6. MP5User

    MP5User Active Member

    2,288
    12
    Westfield
    Yes, interchangeable terms. KWA often uses the word cylinder.
     
  7. Noah_6

    Noah_6 Active Member

    1,045
    8
    Burbank
    I used to have a KWA Mp9. The 2 major causes of this problem were the air nozzle and the stacking of bbs in the magazine
     
  8. Pirate223

    Pirate223 New Member

    481
    0
    I remember having the cylinder crack in one of my MP9s. It never created any issues and the gun was still field-able if I remember correctly. You'll definitely want to replace that anyway, though. It might be something to do with where it cracked. I'm sure it can crack\break in several ways that would cause this.

    While you're at it, I'd still suggest getting another dis-connector spring just in case that is the issue.
     
  9. not_an_noob

    not_an_noob Member

    98
    0
    San Francisco
    Okay guys. So I recently received the cqb bolt for the gun, and it doesn't fit. I also looked at some pictures of what the normal bolt should look like and I noticed that there were several differences between the one that I have and what it should look like.

    My bolt says "Cal. 9x19 mm" instead of saying "Cal. 6.00 mm."

    My bolt also has larger openings in the front for the guides (the cqb bolt wouldn't fit on the guide).

    The back of my bolt curves inward instead of staying flat.

    The seal in my bolt is green and clear instead of orange.

    Could this just be because my kmp9 was said to be a few years old by the original owner? I couldn't imagine parts being incompatible just because it's older. Is it possible that it could be a knock off gun or possibly the ksc version? I was told that kwa parts would work with ksc. I'm really confused.
     
  10. MP5User

    MP5User Active Member

    2,288
    12
    Westfield
    Pictures would help, as well as pictures of your gun as a whole.

    The seal color doesn't really matter.

    Are the curves distinct and in design? I'm also confused on which bolt is which. The undersides of bolts get worn from the hammer.