Ccctennis, very nice! Here is my attempt at a gun rack with supplemental shelving. Not quite finished yet, I hope to take a router and clean up the edges. Also waiting for the weather to be nicer so I can take it out to the garage and stain it a nice dark tone like you have yours. For the gun barrel rests I used a hole saw but I just set the pilot bit in about 1/4" from the edge. So there is a bit of concavity to it, but I intend to smooth that out prior to finishing. I also used a masonite backer just to keep my stuff from falling out the back side.
Lots of other good ideas and tips from this thread, I may have to utilize as well!
If anyone wants the plans/cut sheet PM me.