FYI: CORE15 300BLK upper flash hider: they used some kind of Thread Locker

Aniest

Aniest

CGN Ultra frequent flyer
Location
Edmonton city limits and east
Edit: March 2019. Doing an "old post" review of my activity on CGN: All AAC muzzle devices use Rockset thread locker.

As seem to be turning into an "upper freak" I purchased one of the CORE15 M4 TAC V2 Direct Impingement Upper Receiver .300BLK from Wanstalls (their URL) just before Christmas.

I decided to re-index the Advanced Armament 7.62 Non-mount Blackout Flash Hider. A very long story short, after vicing the barrel with a barrel vice block I came to the conclusion (since a 16" wrench wouldn't budge it) that I needed to heat the flash hider: the result was "cooking" out some sort of "yellowy-white epoxy looking stuff" that once hot allowed me to turn the hider. Luckily, it only took low heat for 10 seconds with a propane soldering torch to get it moved, as I didn't want to damage anything. That same "stuff" when allowed to air cool turned to crystals and had to be heated again for 5-6 seconds to get them out of the threads with a brass brush. I don't know what "that stuff" was, but I thought I'd make this post to warn anyone trying to remove one of these.
 
Last edited:
Ahhh ya...

They likely used Rockset
MD_Expl-426x600.jpg
 
Good luck getting answer from core15, i sent 2 emails over 4 weeks and never had response from them regarding my 300blk upper.
 
Just as a quick update, re-indexing the Flash Hider helped a lot: the dirt/snow/etc thrown around is more even and not back to the shooter so much. Being more even to both sides in the prone position at least made me FEEL it was less.

Also, I two fast notes (sorry, don't do range reports):
1. I tried the subsonic Federal Express 220gr (R300AAC8): it got horrible groups and was obviously designed for a pistol length gas system or something (not enough to cycle the system fully, would not grab a round from the mag, brass wasn't fully ejected all the time and I could hear the recoil spring "twang" under my cheek).
2. I tried 110gr and 125gr bullets in supersonic ammo, and even with the 1in7 twist they did well (sub inch groups at 50 yards). Flat base rounds did better than boat tails: even the Remington Match 125gr (RM300AAC9) being a boat tail didn't group as well as cheaper Remington CTFB 125gr (L300AAC2).

Overall, I Thank Wanstalls for an excellent, fast and simple sale; and I recommend that if you are in the market for a 300BLK AR think about grabbing one of these uppers (slide it on that favorite lower that fits you "just right") from the good CGN sponsor Wanstalls: ammo is out there and the CORE15 people did an excellent job (other than my personal dislike of the flash hider indexing). :D
 
You must log in or register to reply here.
Back
Top Bottom