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Posted: 7/1/2006 6:39:17 PM EDT
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Is there a problem with the bolt. Shinny places. Gun jams. Looking for a reason. I think upper reciever has been machined wrong. Cannot give you upper maker. I know who. They have it. I think I maybe getting the run around. Will see. I have had other problems with upper before jamming was addressed. Thought from the first time I fired the gun that it was the magazines. After buying five differant brands, I have made up my mind that it is the upper. img114.imageshack.us/my.php?image=bolt38ld.jpg img114.imageshack.us/my.php?image=bolt26sx.jpg img114.imageshack.us/my.php?image=bolt14sa.jpg img65.imageshack.us/my.php?image=bolt2iz.jpg |
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Idea, Take a photo of your key bearing sides, then upper receiver bearing track that the key is trying to eat through. Now once that is had time to set in, go about lapping/polishing the bearing sides of your key to prevent them from doing any more damage. Also, the bolt appears to be/run very dry (without lube), and just hoping that you have not been running the rifle to break it in without CLP lubing all the upper bearing area surfaces to allow them to mate/break in. |
| I took the new upper apart and sprayed CLP on everything. Did not wipe anything off. The bolt was trying to hang up in blot carrier ,when moving it in and out by hand. So I made sure everything had lot of CLP on it. Gun would still jam up or have to use forward assist. When I got the new upper the first thing I noticed was the front A2 site was miss machined. One blade was about twice as thick as the other. That was replaced. Then I noticed the ejection port cover would not close unless you use a screw driver to push down spring loaded latch. Now I am thinking two things wrong with upper. Front site and ejection port machined incorrectly. What else was not machined correctly. I used a hand grinder on spring loaded latch to move radius down to latch mount. That made it work, but it was still hard to latch. I have only shoot two hundred rounds out of upper in last six months. It has never fired a clip without a malfunction. It works somewhat better if you have CPL running out of every hole while shooting. If you look down the bolt carrier where bolt goes you see tool marks where it was machined. Being a machinist I know if you have tool grooves that means it was not machined correctly and probably not round or on size. There is wear marks in the upper where bolt carrier rides. Marks just on one side. Also looks like carrier is moving too far forward. Manufacture has upper. Cannot take anymore pictures. If I had to do all over again, I would have shipped the upper right back and asked for my money back. |
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This upper does not have a standard AR15 type gas system does it ? Buy the looks of the bolt would it happen to be a Gas Trap or Piston type upper ? Instead of direct gas impingement. This might be a long shot, just taking a guess on this. That would explain no gas rings on the bolt if I understand correctly. By the way what type of finish is on your bolt ? |
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