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Posted: 2/11/2013 2:26:48 PM EDT
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Helped a friend build a 9mm AR. Used a 9mm hammer and a complete JSE complete 9mm upper. In function testing, the charging handle cannot be pulled to the rear unless the hammer is pulled back before closing the halves together. I swapped the 9mm upper to a known working 5.56 lower and everything worked properly. I swapped the problem lower to a known good upper and everything is fine. Therefore the problem is the combination of the 9mm hammer and the 9mm upper. Is there a known problem using a 9mm hammer with a 9mm bolt or did I just get "lucky" and get the one in a million. Guess we can go to the std hammer and be ok since we are using the 9mm bolt or ?
thanks for any help |
| The "9mm hammer" is a weird thing that seems to only work on UN-ramped 9mm bolts. It does not work for .22 conversions or standard center fire bolts (at least not consistently, across the board). A standard rounded hammer (sometimes called a DPMS hammer) which is basically an M16 hammer without the tail for an auto sear, works with everything, even un-ramped 9mm bolts. It is probably that 9mm hammer that is the problem... |
| Hey guys new to this. I am waiting on a DDLES complete lower, I assume it will be built with a 9mm hammer. Do I need a ramped 9mm bolt, or will a standard 9mm bolt work ex(colt,rra,cmmg). I would contact them but they are off the grid trying to catch up on orders (I hope). Other threads on here are alluding to this. Any expertise on this would be greatly appreciated. |
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