Question on Mossberg O/U

[shooter.45]

I finally shot my NIB Mossberg Silver Reserve O/U shot awesome. This is my first O/U. I cleaned it when I got home after about 25 rounds and there was black almost like peeling inside both barrels when cleaning. Just wondering if this is normal it did not do it on my Mossberg Pump. After getting all the pieces out after swabbing for a while it looks smoother could it have been a film in the barrels??

 

[Dave McCracken]

Might be some preservative. Did you clean before shooting?

 

[shooter.45]

I did I ran a couple of patches with Oil on it and just a little residue but not what looks like peels.

 

[Dave R]

When I bought my Mossy 835 I noticed the same thing. I did clean it before shooting, but it still had the black flakey stuff. It did not want to come off with normal cleaning. Must be related to cosmoline or something. I finally got it out of the bore with brake cleaner on a bore mop.

After that, no flakey stuff.