Bushmaster Upper Question

[kidao35]

Does anyone know what Bushmaster used to coat the inside of the upper receiver? It appears to be a medium gray, matte finish.

The reason I ask is I noticed some of it starting to peel away in spots after my last cleaning. Its coming off as if it were a paint, vs. some kind of parkerizing. I don't believe I used anything on it I haven't used before (propanol-based brake cleaner, followed by some compressed air). The rifle has is a newer post-ban (XM-15E2) with only about 700 rounds through it.

I don't think it contributes much in the way of lubrication to the bolt carrier, however I am concerned bits of it could foul things up.:confused:

BTW, this question is also posted over in the uppers forum.

Thanks in advance.

[oclvtrek]

It's a moly coat spray (molybdenum disulfide) that Bushmaster uses as a dry film lubricant to help with the break in period. It's perfectly normal for it to peel away as you get some rounds through it and clean it. Nothing to worry about.