I noticed a what appears to be patina/discoloration on the inside of a flash hider of a few BCM uppers. It also appears right above my crown. Is this an issue for concern - will it affect accuracy?
Here is a photo:
It’s simply oxidized fouling. If it bothers you, solvent should remove it.
Some lubricants/degreasers/solvents can contain sulfur which can react with copper fouling and give a blue-green appearance as well.
It’s just a reaction of the copper and the cleaning solvents nothing to worry about. Get a brush and clean it out.
Your rifle is junk, and is unsafe to shoot. Feel free to send it to me for proper disposal. I’ll even cover the shipping… :sarcastic:
It’s probably from your solvent and cleaning process. Not a concern. Scrub it out with a brush if it bothers you.
You should see the Flash hiders that the Suppressors screw on to.
The last one I looked at actually had a Light blue coloring to it on the out side.
No worries- keep shooting it.