If the scratches are on the film itself, look to see which side they're on. I'll bet that they'll be on the emulsion side if they're on the film. The backing paper should protect the film from scratches on the base side. One you figure out which side they're on, hold the roll up to the camera back, remembering that the images will need to be "upside down" when held against the back. Then look along your film transport for any surface the emulsion comes in contact with. There might be burr or a tiny piece of grit somewhere.