Unless you can walk completely around the bench, four feet wide is too much. I wouldn't go wider than 30". At four feet, you will never reach the back. I would also make it counter top height or a bit higher if you're taller. I found that a bit taller is most comfortable for reloading.
You could make the frame out of superstrut and add "feet" to it and bolt it to the floor. Then, add 2x's the 30" way for added support. On top of that a sheet of 3/4 plywood or a maple butcher block top with several coats of poly. Router a couple grooves for 80/20 extruded channel.
I have shelves behind the bench, but they are hanging from the floor joists. This way if the table moves at all (highly doubt it being bolted to the floor, but you never know) anything on the shelves won't fall over.
Last edited by sackett; 01/22/14.
