I noticed a used 20ga youth NEF today that was unusual (to me) in that the frame was polished and blued like a rifle frame. It was wearing grey laminate straight-grip stocks drilled for sling swivels and had a factory recoil pad. NN prefix.
I didn't think to look and see if the firing pin looked big or small, and I'm sure this shop wouldn't let me remove the buttstock to check the frame. I'm wondering if this may be a rifle frame. Any guesses? I was hoping it may have been a combo gun at one time that got split up.