I have just finished my first Ar pistol build in 9mm. Everything worked out great except that when I fire the pistol the action will chamber the next rnd but not reset the trigger. When manually racked the trigger resets as soon as the bolt clears the next rnd enough to chamber it,but not when fired. The kit came with a blade brace with buffer tube assembly. Thinking that maybe the buffer spring was too strong i swapped it out with another that wasnt as new and stiff but made no difference. Any help on eliminating this problem without having to return the upper to the dealer for who knows how long would be greatly appreciated. Thanks ET.
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9mm ar pistol question.
- Thread starter ET762AR
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- Jan 7, 2013
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Check the buffer length vs the length of the tube? It may come back far enough to eject but not reset the hammer?
What kind if trigger do you have? Is it possible that the hammer is following the bolt back down? Do you have another that you could try?
Also, what kind of ammo are you using? Full power?
Also, what kind of ammo are you using? Full power?
Often uppers and lowers need to be from the same manufacturer.same with bolts. Is it Colt based or Glock?
There are compatibility issues in the 9mm AR world.
There are compatibility issues in the 9mm AR world.
I know this sounds strange, but check the inside of the buffer tube to see if it is smooth. I ordered a Kak Blade assembly and had issues on a 7,62x39 build, the inside of the buffer tube was so boogered up that the spring was catching on the tube.
Does your hammer look like this?
Or something like this?
Or something like this?
Also if it's a dedicated 9mm AR hammer it will not work with a ramped bolt.
E
ET762AR
, I had this very same problem building mine. I was using a cmc drop-in trigger. I replaced with milspec and worked better, but now I have a little sticky reset. It's a cmmg trigger group which I have been told are crap. The cmc didn't have the hammer spring loaded in correctly so now I need to retry it.
Often times the shorter hammers will not work with PCCs. Is it a short hammer, like a CMC, or full size?
I used a standard LPK in my QC10 Colt 9mm lower and use a QC10 Bolt.....had to beef UP the recoil spring and buffer weight to slow the bolt down so it wouldn't snap my LRBHO and now it works like a champ. Never had an issue with trigger reset.
