There is no case coloring on the receiver. When it was cleaned and sanded to 800 grit it looked just like the other parts but when I started to apply bluing it never did get the deep blue color of the other parts. After curing for 4 dayd with oil on it, it looked brown and as I carded it, it just got a dull washed out brown color to it. It looks like it was cleaned and then stain put on it. I am going to clend, strip and start over but thought the acid bath might inprove.