Seems like lots of folks are building reloading benches right now! Mine is primarily for working on my guns, but has plenty of space for reloading equipment when I can afford to make that investment.
Top surface is 8ft long, 2ft deep, and 34 inches off the floor. It is 2 pieces of 3/4 inch plywood glued and screwed together, and also glued and screwed to the frame of the bench. It has 3 2x4s running the length of it for added (and probably unnecessary) strength and rigidity. In the first picture it looks a little out of square, but it's just the perspective.. It's definitely square.
Gluing the two sheets of plywood together for the top surface:
After applying the glue, I set the bench upside down on top of the top surface and ran 1 1/4" screws in from the bottom. There are no screws on the work surface, which is a nice touch I think.
It has a 4inch overhang on the front for mounting tools, vices, and reloading equipment.
I had an extra sheet of plywood left over, so I glued and screwed it to the bottom for added strength and a little extra height. The piece of plywood on the floor behind the bench needs a little trimming tomorrow so it can be glued and screwed to the top of the bottom horizontal 2x4s for a shelf. Eventually this bench will be up against a wall and that wall will have shelves and pegboard on it for organizing and hanging tools, guns, or whatever.
As it stands now, it probably weighs close to 200 lbs. I plan on loading up the bottom shelf with ammo and other heavy stuff so that the bench doesn't move when applying torque to the mounted tools, vices, and presses. I might add cross bracing later if it needs it, but this thing is really solid as is. After I add that last piece of plywood as a shelf, I'm going to take a belt sander to all the edges and round them off just a hair so that I don't get splinters or have hard edges.
Total cost was $110 with 80% of that being the 2 sheets of 3/4" plywood.