I would also check it under some bright lights...or outside in the sunlight. Certain imperfections can only be seen in good light.
I would also take that barrel out of the slide and look at the riflings. They should stand out quite nicely and not have any noticeable nicks or rust.
I would also take that barrel out of the slide and look at the riflings. They should stand out quite nicely and not have any noticeable nicks or rust.