Bottom of Op Slide Box rubbing inside stock

Last week, looked over a QHMC for a fellow rifle club member.
Action was slow, could feel a little binding.
Cleaned it inside and out.
Found fresh rub marks on the bottom of the stock's inside channel from the bottom of the Op slide box rubbing on it.
I've seen this once before, caused by a crack on the stock, but this stock seemed to be solid during a quick inspection.
Was the recoil plate seat crushed? Could see no sign of it.
No bends on the slide. Slide Lugs looked fine. Receiver rails in good shape.
Spring tube was straight and snug.
Has a Type III bayo band. Made sure the barrel was seated and hung correctly and had a snug fit to the recoil plate.
No sign of any warpage of the type II stock. Didn't think about it while he was here, but should have tried another stock.
He'll be back with the carbine this weekend, so I can spend the last couple days of my Daughter's leave time with her, but can't get this off my mind.

Anyone ever run across this?
Thoughts?

TIA,
Charlie-painter777

Charlie, My IBM rubs a bit in the same place - but it runs OK. On mine, I think it's in the stock - maybe the wood is compressed some where the barrel band fits. I haven't tried mine in a different stock yet. - Bob

Maybe it swelled over time, thus causing the rubbing. Couldn't you just sand it a bit? Or would that be a no no.

Sand it and shoot it if nothing else can be found wrong.

Come to find out the owner had been storing this carbine in his garage. Said his wife isn't comfortable with guns in the house.
After leaving it inside for this past week or so.
I can find no sign of any further rubbing.
Last few weeks have been very cool and soggy.
Huge difference after leaving it inside.

Hard to understand 'Feeling safer' with a firearm stored on a shelf in a detached garage :nono:

FWIW,
Charlie-painter777

Well, if she locked the door at night, it wasn't going to come inside on it's own and harm her. hehehehehe. Although it gave a burglar a better chance to have it. Good thing is I would think most people, possibly even bad guys, don't travel with a stash of .30 carbine if they don't own one. Although I've never been a burglar, so I wouldn't really know. Hehehhe

glad it got sorted though.