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Posted: 7/17/2006 3:18:58 PM EDT
| Changing the flash hider on my 6920 and noticed the new one does not index properly. It has cutouts on the top and they go past where they should be about 1/4 turn before stopping. What can I do to fix this problem? |
Get a new crush washer and you'll be good to go. |
I ran into the same thing with my YHM Phantom 5C2. I don't have any way of securing the barrel because I'm too cheap to buy any real tools (barrel vise, action block, etc.), so I used a wrench and my knee on the front sight base against the floor. No way in the world could I get that 5C2 to line up with the closed section on the bottom - it was going to have to be way over-torqued to get it right. So, I took a file and filed down the crush washer on both sides until I got it where I wanted it, used blue loc-tite on the threads, and tightened it as hard as I could without tearing my knee off. Seems to work fine, but I'm no power-AR-user who has to have this work to save his life, so YMMV.  I tried both the old crush washer and the new crush washer that came with the 5C2, by the way. Neither one would "crush" at all until I filed on the new one, then it finally crushed enough to get the FH where I wanted it. |
Crush washers are not supposed to be reused and had you had that barrel mounted in a vice somehow (receiver claw or barrel vice), you could have used the new lock washer that came with the FH without filing it or using lock tight or any of that non-sense. Crush washers do not "crush" easily and take a little more torque than the average person can apply holding the barrel down with their knee. In your case, you would have probably been better off using a peel washer. |
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