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Flash suppressor lock nut walking out on me...

1288 Views 5 Replies 4 Participants Last post by  m14dan
I took my baby to the range a few days ago, and during the cleaning I noticed that the set screw on the flash suppressor had "walked out" and that the lock nut had backed off about 1/8 turn. I had tightened the flash suppressor down after I had noticed it was loose and was picking up streaks of copper from bullet strikes. Thought that was the end of it, but no such luck. Should I use Loctite on the set screw, or just tighten the holy hell out of it and re-tighten as needed?
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:wink: If you have the Set Screw in one of the Recesses on the Castle Nut How can your Castle nut get loose? May be I dont understand your Question? :?:
DO NOT tighten the holy heck out of the set screw. That is very detrimental to accuracy. Drive the flash hider down as far as it will go with a mallet. SNUG the castle nut down with your fingers. Install the set screw into a slot with red locktight on it and check your alignment. If you have to moc\ve the castle nut to get the setscrew in then back it off a little. Don't tighten it with priers. If your flash hider is loose in any way then disregard everything I just typed. The castle nut keeps the FH from moving axially. Not the other directions. Anyway don't jam inthe screw but screw it in just enough to keep the castle nut from turning. That will be a properly installed and tuned flashhider.

If your flash hider can be slid on by hand or you can wiggle it up and down at all then completely disregard everything I just said! This is only good for ones that fit tight and right and a loose one is begging for a bullet strike.
Always check your alignment when you have messed with it!
The set screw "walked" out during my last shooting session, and the castle nut has backed off about 1/8 turn, which mis-aligned the notch that the set screw was seated in. I will try using the mallet to drive the FH back down some and re-aligning the castle nut. I'm assuming that the castle nut should be finger tight, not cranked on there with pliers?

Thanks for the info!

I had to disassemble a rifle that had loctite on the set screw and I had to use a saw to get the flashhider off. Very sad to have to cut on my favorite rifle. If you do what has been said so far you should be ok.
That happens sometimes. Maybe the thing was rounded out or something. On a screw so tiny it wasn't from the locktight. There are metric and standard setscrews out there and people commonly round out the head. I'm not saying you did, just a possibility. Them setscrews are getting hard to find but they are cheap when you do. If it even looks like it's starting to round out then replace it.
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