New O/U grinding shot shell rim on receiver wall

[Gibo]

New to gun ownership so sorry if dumb question.

Got a 12ga Franchi Instinct L recently and took it out to test, action was a bit stiff but that's not surprising.
After I got home I tested out the trigger pull with some snap caps but I couldn't close the receiver if the bottom chamber was loaded if only the top chamber was loaded I could close the receiver.
Looking at some of my spent shells I realised the rims of the casings were a bit shaved meaning shells loaded in the bottom chamber where being rubbed against the back of the receiver when closing.

Is this normal for o/u shot shells or should I get it serviced?

 

[fire@will]

No - not normal. Should be a close fit - but not rubbing.

 

[Ashcroft]

Maybe a tiny piece of grit caught under the lower extractor preventing it from completely retracting as the gun is closed?

 

[IvoB]

when you break open your shotgun make sure that it is all the way - perhaps oil the hinge area as well.

 

[Gibo]

Striped gun, clear signs of rim grinding with metal shavings getting caught in bottom firing pin.
Will be claiming insurance on this probably qc issue.