If you had asked this question 10-15years ago, I would have emailed you a complete set of plans for a wooden bench that could be used left-or-right handed, was an update of benches used at a state organization's range, which I built a half dozen of, and which served my own club for well over ten years.
But those benches also had flaws, big and small, and besides, I don't have the image files anymore. In essence, no one design is going to work for all users.
Answer these question (for yourself, not me) and then proceed from there.
Will the bench need to serve more than one shooter over time? Will it need to be moveable? Transportable? Accommodate uneven ground? Soft ground?
Some features I recommend:
That the shooting surface itself be at least 42" front to rear. That it be capable of being leveled, and that it has a means to prevent it from rocking (note, a tripod base arrangement is naturally secure and stable, but must be wide enough set so it cannot tip). That it have a slight lip (1/4" or less) all around to prevent items (like a cartridge) from rolling off. If a seat is incorporated, that the bench/seat combination be secure enough to prevent the rifle from being disturbed by the shooter's movement. Provides some convenient space to place a spotting scope. I like a slight forward pitch (front very slightly down), to allow for the easier employment of bipod, rest, rear bag, etc. It is better for the bench to be bigger than smaller, and the layout must avoid forcing the shooter to stretch over or around any portion of its shape. If portable, it needs to fit the transporter, and if that requires it to be segmented, those segments must be light enough to be moved reasonably and couple rigidly enough that the original purpose is not compromised.
Finally, benches that stay outdoors have a nasty habit of harboring ticks and wasp nests on their underside. Make point of observing the undersides of the supporting surfaces before climbing aboard. Keeping a can of wasp and or insect killer spray available never hurts.
My bench design was made from 2x4 lumber and 3/4" plywood, laid out so three 32" square benches could be made from single sheet. In practice, they worked, but really needed to be considerably bigger. They were extremely rigid yet light, owing to making the legs by screwing the 2x4's together so they had an 'L' shaped cross section, there legs were tied together at the bottom by horizontal skids, and several of the excess plywood panels were employed as gussets. There was literally no scrap left after construction.
Greg
