Rust on barrel threads

AR/M4 AR Technical Discussion
1

I removed my m4-2000 mount so that I could install my N4 shorty barrel into a new VIS II. I degreased the barrel threads for reassembly and noticed, what appears to be, some rust. Should I be concerned?

Also an oversight on my part is going to delay reassembly, should I oil the threads and then degrease them again before install? Or will the untreated parts be ok for a couple of days? Thanks in advance for your help.
Charles

2

I’d have to see a pic of how bad to make that call. I’d, at a minimum wire brush off the rust.

3

Sorry Mark, but I don’t have access to a camera. The rust is at the rear of the threads furthest from the muzzle. It only covers one thread. I brushed it the best I could.

4

I wouldn’t even worry about it then. It doesn’t sound wide spread.

You could hit it with CLP and the brush and “degrease” it before you reinstall the mount.