Brake rotor question

[70 RAG TOP]

I installed new brake rotors on the front of my challenger and only have about 500 miles on them.  I just happened to be under the car checking something else and noticed a 1/4" wide , fairly deep gash in the inside face of the rotor that goes about half way around the diameter of the rotor.  The depth of the gash starts out deep and gradually gets shallower as it gets to the end of the gash.  Nothing seems to be dragging now.  It almost looks like something might have gotten stuck between the rotor and the pads and briefly caused the gash.  Does anyone have any ideas?  Could the rotor have been warped right out of the box?  Could my spindle be bent?  I don't remember my old rotors having the gash , so I think this a new development.
Thanks for your help
Mike

[cudazappa]

Sounds like a rock got stuck to me.  If the rotor can't be turned to remove the gash, then you should replace it

[ChallengerHK]

That was my first thought to, but it's hard to believe that you wouldn't have heard that happening.

[72cudamaan]

A picture would be worth about a zillion words here. What do you define as a "gash"? If the rotor was warped you
would have and would still feel a pulsation. Do you? Unless your caliper is not working properly, the clearance between the pad and rotor is miniscule. No room for a rock. And if the caliper wasn't working properly and left room for a rock, you would have a terrible pull when the brakes are applied.  Do you? And if the "gash" is fairly small as a % to brake surface area, I would leave it alone. No sense in junking a good rotor by trying to turn it out on a lathe or throwing it away.