huntsman22's bench is one nice setup.
I had the high school carpentry class put one together for me many, many years ago. I found the plans for it in some hunting magazine, but can't remember where. It is built out of two pieces of 3/4" plywood and they glued them together and sealed it with something that is really impervious to just about anything I have spilled on it. The legs are made from 1 1/2" black pipe and are 29 1/2 inches long. The top, in the front, is 27" wide and it runs that width for 15 3/4" towards the back and then there is a taper that angles in on each side that is 9" long to make room for the shooter to get behind the rifle. The taper stops and then the wood runs straight to the back for 15". The narrow part at the back is 14 3/4" wide. It is an ambidextrous bench and looking back, I wish I would have just had it made for right handers.
Just for kicks I found the receipt for the cost of the bench:
Pipe-----------------$ 5.25
Couplings------------- 4.68
Bolts, nuts, washers---1.44
Plywood---------------9.44
TOTAL--------------$20.81
I used to haul this thing out to the rifle range before they had cement benches built there. It isn't something you would want to lug around for prairie dog shooting though. When I use it for a cleaning station in my reloading room I have the gun vise turned the other way so the butt of the rifle is on the narrow end of the bench and the barrel is out on the wide end just like you'd have it while shooting.
I have it set up as a cleaning station in the photo below.
The next photo shows the underside. The pipe nipples are welded to a plate which is fastend to the bench using carriage bolts. The nipples are welded onto the plate a a slight outward angle.
The next photo shows how I have installed conduit hangers on the bottom where I place the legs and then use lag screws to tighten the hangers so the pipes don't fall out. I have also installed a handle on the bottom for ease of carrying the whole thing. It is one heavy bench and it doesn't move around if you use it for shooting.