Transparency from copied art not adjustable

Hi, I'm having some trouble with transparency in an illustrator file. I was working on a template file, and had set my layer that contained my artwork to multply and 80% transparency so that I could more easily see the template. Later, I was sent a new template file, since the original wasn't scaled properly and had a few mistakes. I copied the entire layer including all sublayers of the artwork to the new one.. scaled it to fit, and then continued working. Now I'm done, and just went to change the blending mode/transparency back to normal and 100%, but it says it already is set to both. It still looks/acts like it's semi-transparent, and nothing I do will get it back to full opacity.. it all appears to be already there according to all the settings (checked the layer, as well as individual objects) but it's not. This is black & white art, so at the moment it looks like a dark grey... Any idea how it may have copied the appearance, but not the actual settings? Every object is still filled with black, but appears dark grey. I'm stumped! Thanks.