Residue buildup under flash hider

AR/M4 AR Technical Discussion
1

I have a relatively new M4-2000 silencer that saw its first extensive use at the silencer shoot last weekend. When I got around to cleaning the rifle, I noticed a white residue that was coming out from under the flash hider. I’ll try and attach a picture. Does anyone have any idea what this residue may be? It does scrape off and is brittle.

The gun in question has a 16 inch barrel. When I first got the silencer, I temporarily attached the flash hider/silencer mount using blue locktite. A couple of days before the shoot, I removed the mount, cleaned the barrel threads and mount with acetone, then reattached the mount using the supplied rockset.

I posted a similar thread on this topic over on silencertalk.com, but no one has answered my question. I’m guessing it might be residual adhesive, or maybe gas is somehow venting back thru the attachment, but I don’t know. I thought I’d ask if anyone here has seen something like this before.

Thanks.

2

You probably just used too much Rocksett and it oozed out from under the flash hider. Did you wait for it to dry/cure for 24hrs before using a supressor on it?

3

Thanks for your quick reply. Yes, I did wait at least a day, probably more like a day and a half. I hope it is just extra rockset that oozed out. I can clean it up this time, and not wonder what’s going on. Also, the gun did get hot that day from use.